Merge pull request #367 from telemt/bump

Update Cargo.toml

CONTRIBUTING.md

@@ -1,3 +1,8 @@
+# Issues - Rules
+## What it is not
+- NOT Question and Answer
+- NOT Helpdesk
+
 # Pull Requests - Rules
 ## General
 - ONLY signed and verified commits

Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "telemt"
-version = "3.2.0"
+version = "3.3.10"
 edition = "2024"
 
 [dependencies]

README.md

@@ -2,7 +2,12 @@
 
 ***Löst Probleme, bevor andere überhaupt wissen, dass sie existieren*** / ***It solves problems before others even realize they exist***
 
-**Telemt** is a fast, secure, and feature-rich server written in Rust: it fully implements the official Telegram proxy algo and adds many production-ready improvements such as connection pooling, replay protection, detailed statistics, masking from "prying" eyes
+**Telemt** is a fast, secure, and feature-rich server written in Rust: it fully implements the official Telegram proxy algo and adds many production-ready improvements such as:
+- [ME Pool + Reader/Writer + Registry + Refill + Adaptive Floor + Trio-State + Generation Lifecycle](https://github.com/telemt/telemt/blob/main/docs/model/MODEL.en.md)
+- [Full-covered API w/ management](https://github.com/telemt/telemt/blob/main/docs/API.md)
+- Anti-Replay on Sliding Window
+- Prometheus-format Metrics
+- TLS-Fronting and TCP-Splicing for masking from "prying" eyes
 
 [**Telemt Chat in Telegram**](https://t.me/telemtrs)
 
@@ -14,18 +19,24 @@
 
 ### 🇷🇺 RU
 
-#### Релиз 3.0.15 — 25 февраля
+#### Релиз 3.3.5 LTS - 6 марта
 
-25 февраля мы выпустили версию **3.0.15**
+6 марта мы выпустили Telemt **3.3.5**
 
-Мы предполагаем, что она станет завершающей версией поколения 3.0 и уже сейчас мы рассматриваем её как **LTS-кандидата** для версии **3.1.0**!
+Это [3.3.5 - первая LTS-версия telemt](https://github.com/telemt/telemt/releases/tag/3.3.5)!
 
-После нескольких дней детального анализа особенностей работы Middle-End мы спроектировали и реализовали продуманный режим **ротации ME Writer**. Данный режим позволяет поддерживать стабильно высокую производительность в long-run сценариях без возникновения ошибок, связанных с некорректной конфигурацией прокси
+В ней используется:
+- новый алгоритм ME NoWait для непревзойдённо быстрого восстановления пула
+- Adaptive Floor, поддерживающий количество ME Writer на оптимальном уровне
+- модель усовершенствованного доступа к KDF Fingerprint на RwLock
+- строгая привязка Middle-End к DC-ID с предсказуемым алгоритмом деградации и самовосстановления
 
-Будем рады вашему фидбеку и предложениям по улучшению — особенно в части **статистики** и **UX**
+Telemt Control API V1 в 3.3.5 включает:
+- несколько режимов работы в зависимости от доступных ресурсов
+- снапшот-модель для живых метрик без вмешательства в hot-path
+- минималистичный набор запросов для управления пользователями
 
-Релиз:  
-[3.0.15](https://github.com/telemt/telemt/releases/tag/3.0.15)
+Будем рады вашему фидбеку и предложениям по улучшению — особенно в части **API**, **статистики**, **UX**
 
 ---
 
@@ -42,18 +53,24 @@
 
 ### 🇬🇧 EN
 
-#### Release 3.0.15 — February 25
+#### Release 3.3.5 LTS - March 6
 
-On February 25, we released version **3.0.15**
+On March 6, we released Telemt **3.3.3**
 
-We expect this to become the final release of the 3.0 generation and at this point, we already see it as a strong **LTS candidate** for the upcoming **3.1.0** release!
+This is [3.3.5 - the first LTS release of telemt](https://github.com/telemt/telemt/releases/tag/3.3.5)
 
-After several days of deep analysis of Middle-End behavior, we designed and implemented a well-engineered **ME Writer rotation mode**. This mode enables sustained high throughput in long-run scenarios while preventing proxy misconfiguration errors
+It introduces:
+- the new ME NoWait algorithm for exceptionally fast pool recovery
+- Adaptive Floor, which maintains the number of ME Writers at an optimal level
+- an improved KDF Fingerprint access model based on RwLock
+- strict binding of Middle-End instances to DC-ID with a predictable degradation and self-recovery algorithm
 
-We are looking forward to your feedback and improvement proposals — especially regarding **statistics** and **UX**
+Telemt Control API V1 in version 3.3.5 includes:
+- multiple operating modes depending on available resources
+- a snapshot-based model for live metrics without interfering with the hot path
+- a minimalistic request set for user management
 
-Release:  
-[3.0.15](https://github.com/telemt/telemt/releases/tag/3.0.15)
+We are looking forward to your feedback and improvement proposals — especially regarding **API**, **statistics**, **UX**
 
 ---
 
@@ -76,31 +93,6 @@ We welcome ideas, architectural feedback, and pull requests.
 
 ⚓ Our ***Middle-End Pool*** is fastest by design in standard scenarios, compared to other implementations of connecting to the Middle-End Proxy: non dramatically, but usual
 
-# GOTO
-- [Features](#features)
-- [Quick Start Guide](#quick-start-guide)
-- [How to use?](#how-to-use)
-  - [Systemd Method](#telemt-via-systemd)
-- [Configuration](#configuration)
-  - [Minimal Configuration](#minimal-configuration-for-first-start)
-  - [Advanced](#advanced)
-    - [Adtag](#adtag)
-    - [Listening and Announce IPs](#listening-and-announce-ips)
-    - [Upstream Manager](#upstream-manager)
-      - [IP](#bind-on-ip)
-      - [SOCKS](#socks45-as-upstream)
-- [FAQ](#faq)
-  - [Recognizability for DPI + crawler](#recognizability-for-dpi-and-crawler)
-  - [Telegram Calls](#telegram-calls-via-mtproxy)
-  - [DPI](#how-does-dpi-see-mtproxy-tls)
-  - [Whitelist on Network Level](#whitelist-on-ip)
-  - [Too many open files](#too-many-open-files)
-- [Build](#build)
-- [Docker](#docker)
-- [Why Rust?](#why-rust)
-
-## Features
-
 - Full support for all official MTProto proxy modes:
   - Classic
   - Secure - with `dd` prefix
@@ -111,158 +103,40 @@ We welcome ideas, architectural feedback, and pull requests.
 - Graceful shutdown on Ctrl+C
 - Extensive logging via `trace` and `debug` with `RUST_LOG` method
 
+# GOTO
+- [Telemt - MTProxy on Rust + Tokio](#telemt---mtproxy-on-rust--tokio)
+  - [NEWS and EMERGENCY](#news-and-emergency)
+    - [✈️ Telemt 3 is released!](#️-telemt-3-is-released)
+    - [🇷🇺 RU](#-ru)
+      - [Релиз 3.3.5 LTS - 6 марта](#релиз-335-lts---6-марта)
+    - [🇬🇧 EN](#-en)
+      - [Release 3.3.5 LTS - March 6](#release-335-lts---march-6)
+- [Features](#features)
+- [GOTO](#goto)
+  - [Quick Start Guide](#quick-start-guide)
+  - [FAQ](#faq)
+    - [Recognizability for DPI and crawler](#recognizability-for-dpi-and-crawler)
+      - [Client WITH secret-key accesses the MTProxy resource:](#client-with-secret-key-accesses-the-mtproxy-resource)
+      - [Client WITHOUT secret-key gets transparent access to the specified resource:](#client-without-secret-key-gets-transparent-access-to-the-specified-resource)
+    - [Telegram Calls via MTProxy](#telegram-calls-via-mtproxy)
+    - [How does DPI see MTProxy TLS?](#how-does-dpi-see-mtproxy-tls)
+    - [Whitelist on IP](#whitelist-on-ip)
+    - [Too many open files](#too-many-open-files)
+  - [Build](#build)
+  - [Why Rust?](#why-rust)
+  - [Issues](#issues)
+  - [Roadmap](#roadmap)
+
+
 ## Quick Start Guide
-**This software is designed for Debian-based OS: in addition to Debian, these are Ubuntu, Mint, Kali, MX and many other Linux**
-1. Download release
-```bash
-wget -qO- "https://github.com/telemt/telemt/releases/latest/download/telemt-$(uname -m)-linux-$(ldd --version 2>&1 | grep -iq musl && echo musl || echo gnu).tar.gz" | tar -xz
-```
-2. Move to Bin Folder
-```bash
-mv telemt /bin
-```
-4. Make Executable
-```bash
-chmod +x /bin/telemt
-```
-5. Go to [How to use?](#how-to-use) section for for further steps
-
-## How to use?
-### Telemt via Systemd
-**This instruction "assume" that you:**
-- logged in as root or executed `su -` / `sudo su`
-- you already have an assembled and executable `telemt` in /bin folder as a result of the [Quick Start Guide](#quick-start-guide) or [Build](#build)
-
-**0. Check port and generate secrets**
-
-The port you have selected for use should be MISSING from the list, when:
-```bash
-netstat -lnp
-```
-
-Generate 16 bytes/32 characters HEX with OpenSSL or another way:
-```bash
-openssl rand -hex 16
-```
-OR
-```bash
-xxd -l 16 -p /dev/urandom
-```
-OR
-```bash
-python3 -c 'import os; print(os.urandom(16).hex())'
-```
-
-**1. Place your config to /etc/telemt.toml**
-
-Open nano
-```bash
-nano /etc/telemt.toml
-```
-paste your config from [Configuration](#configuration) section
-
-then Ctrl+X -> Y -> Enter to save
-
-**2. Create service on /etc/systemd/system/telemt.service**
-
-Open nano
-```bash
-nano /etc/systemd/system/telemt.service
-```
-paste this Systemd Module
-```bash
-[Unit]
-Description=Telemt
-After=network.target
-
-[Service]
-Type=simple
-WorkingDirectory=/bin
-ExecStart=/bin/telemt /etc/telemt.toml
-Restart=on-failure
-LimitNOFILE=65536
-
-[Install]
-WantedBy=multi-user.target
-```
-then Ctrl+X -> Y -> Enter to save
-
-**3.**  In Shell type `systemctl start telemt` - it must start with zero exit-code
-
-**4.** In Shell type `systemctl status telemt` - there you can reach info about current MTProxy status
-
-**5.** In Shell type `systemctl enable telemt` - then telemt will start with system startup, after the network is up
-
-**6.** In Shell type `journalctl -u telemt -n -g "links" --no-pager -o cat | tac` - get the connection links
-
-## Configuration
-### Minimal Configuration for First Start
-```toml
-# === General Settings ===
-[general]
-# ad_tag = "00000000000000000000000000000000"
-
-[general.modes]
-classic = false
-secure = false
-tls = true
-
-# === Anti-Censorship & Masking ===
-[censorship]
-tls_domain = "petrovich.ru"
-
-[access.users]
-# format: "username" = "32_hex_chars_secret"
-hello = "00000000000000000000000000000000"
-
-```
-### Advanced
-#### Adtag (per-user)
-To use channel advertising and usage statistics from Telegram, get an Adtag from [@mtproxybot](https://t.me/mtproxybot). Set it per user in `[access.user_ad_tags]` (32 hex chars):
-```toml
-[access.user_ad_tags]
-username1 = "11111111111111111111111111111111"  # Replace with your tag from @mtproxybot
-username2 = "22222222222222222222222222222222"
-```
-#### Listening and Announce IPs
-To specify listening address and/or address in links, add to section `[[server.listeners]]` of config.toml:
-```toml
-[[server.listeners]]
-ip = "0.0.0.0"          # 0.0.0.0 = all IPs; your IP = specific listening
-announce_ip = "1.2.3.4" # IP in links; comment with # if not used
-```
-#### Upstream Manager
-To specify upstream, add to section `[[upstreams]]` of config.toml:
-##### Bind on IP
-```toml
-[[upstreams]]
-type = "direct"
-weight = 1
-enabled = true
-interface = "192.168.1.100" # Change to your outgoing IP
-```
-##### SOCKS4/5 as Upstream
-- Without Auth:
-```toml
-[[upstreams]]
-type = "socks5"            # Specify SOCKS4 or SOCKS5
-address = "1.2.3.4:1234"   # SOCKS-server Address
-weight = 1                 # Set Weight for Scenarios
-enabled = true
-```
-
-- With Auth:
-```toml
-[[upstreams]]
-type = "socks5"            # Specify SOCKS4 or SOCKS5
-address = "1.2.3.4:1234"   # SOCKS-server Address
-username = "user"          # Username for Auth on SOCKS-server
-password = "pass"          # Password for Auth on SOCKS-server
-weight = 1                 # Set Weight for Scenarios
-enabled = true
-```
+- [Quick Start Guide RU](docs/QUICK_START_GUIDE.ru.md)
+- [Quick Start Guide EN](docs/QUICK_START_GUIDE.en.md)
 
 ## FAQ
+
+- [FAQ RU](docs/FAQ.ru.md)
+- [FAQ EN](docs/FAQ.en.md)
+
 ### Recognizability for DPI and crawler
 Since version 1.1.0.0, we have debugged masking perfectly: for all clients without "presenting" a key, 
 we transparently direct traffic to the target host!
@@ -407,41 +281,6 @@ chmod +x /bin/telemt
 telemt config.toml
 ```
 
-## Docker
-**Quick start (Docker Compose)**
-
-1. Edit `config.toml` in repo root (at least: port, users secrets, tls_domain)
-2. Start container:
-```bash
-docker compose up -d --build
-```
-3. Check logs:
-```bash
-docker compose logs -f telemt
-```
-4. Stop:
-```bash
-docker compose down
-```
-
-**Notes**
-- `docker-compose.yml` maps `./config.toml` to `/app/config.toml` (read-only)
-- By default it publishes `443:443` and runs with dropped capabilities (only `NET_BIND_SERVICE` is added)
-- If you really need host networking (usually only for some IPv6 setups) uncomment `network_mode: host`
-
-**Run without Compose**
-```bash
-docker build -t telemt:local .
-docker run --name telemt --restart unless-stopped \
-  -p 443:443 \
-  -e RUST_LOG=info \
-  -v "$PWD/config.toml:/app/config.toml:ro" \
-  --read-only \
-  --cap-drop ALL --cap-add NET_BIND_SERVICE \
-  --ulimit nofile=65536:65536 \
-  telemt:local
-```
-
 ## Why Rust?
 - Long-running reliability and idempotent behavior
 - Rust's deterministic resource management - RAII 

config.toml

@@ -4,7 +4,7 @@
 
 # === General Settings ===
 [general]
-use_middle_proxy = false
+use_middle_proxy = true
 # Global ad_tag fallback when user has no per-user tag in [access.user_ad_tags]
 # ad_tag = "00000000000000000000000000000000"
 # Per-user ad_tag in [access.user_ad_tags] (32 hex from @MTProxybot)
@@ -34,6 +34,13 @@ port = 443
 # metrics_port = 9090
 # metrics_whitelist = ["127.0.0.1", "::1", "0.0.0.0/0"]
 
+[server.api]
+enabled = true
+listen = "0.0.0.0:9091"
+whitelist = ["127.0.0.0/8"]
+minimal_runtime_enabled = false
+minimal_runtime_cache_ttl_ms = 1000
+
 # Listen on multiple interfaces/IPs - IPv4
 [[server.listeners]]
 ip = "0.0.0.0"

docs/API.md

@@ -13,13 +13,25 @@ API runtime is configured in `[server.api]`.
 | `listen` | `string` (`IP:PORT`) | `127.0.0.1:9091` | API bind address. |
 | `whitelist` | `CIDR[]` | `127.0.0.1/32, ::1/128` | Source IP allowlist. Empty list means allow all. |
 | `auth_header` | `string` | `""` | Exact value for `Authorization` header. Empty disables header auth. |
-| `request_body_limit_bytes` | `usize` | `65536` | Maximum request body size. |
+| `request_body_limit_bytes` | `usize` | `65536` | Maximum request body size. Must be `> 0`. |
 | `minimal_runtime_enabled` | `bool` | `false` | Enables runtime snapshot endpoints requiring ME pool read-lock aggregation. |
-| `minimal_runtime_cache_ttl_ms` | `u64` | `1000` | Cache TTL for minimal snapshots. `0` disables cache. |
+| `minimal_runtime_cache_ttl_ms` | `u64` | `1000` | Cache TTL for minimal snapshots. `0` disables cache; valid range is `[0, 60000]`. |
+| `runtime_edge_enabled` | `bool` | `false` | Enables runtime edge endpoints with cached aggregation payloads. |
+| `runtime_edge_cache_ttl_ms` | `u64` | `1000` | Cache TTL for runtime edge summary payloads. `0` disables cache. |
+| `runtime_edge_top_n` | `usize` | `10` | Top-N rows for runtime edge leaderboard payloads. |
+| `runtime_edge_events_capacity` | `usize` | `256` | Ring-buffer size for `/v1/runtime/events/recent`. |
 | `read_only` | `bool` | `false` | Disables mutating endpoints. |
 
 `server.admin_api` is accepted as an alias for backward compatibility.
 
+Runtime validation for API config:
+- `server.api.listen` must be a valid `IP:PORT`.
+- `server.api.request_body_limit_bytes` must be `> 0`.
+- `server.api.minimal_runtime_cache_ttl_ms` must be within `[0, 60000]`.
+- `server.api.runtime_edge_cache_ttl_ms` must be within `[0, 60000]`.
+- `server.api.runtime_edge_top_n` must be within `[1, 1000]`.
+- `server.api.runtime_edge_events_capacity` must be within `[16, 4096]`.
+
 ## Protocol Contract
 
 | Item | Value |
@@ -51,23 +63,50 @@ API runtime is configured in `[server.api]`.
 }
 ```
 
+## Request Processing Order
+
+Requests are processed in this order:
+1. `api_enabled` gate (`503 api_disabled` if disabled).
+2. Source IP whitelist gate (`403 forbidden`).
+3. `Authorization` header gate when configured (`401 unauthorized`).
+4. Route and method matching (`404 not_found` or `405 method_not_allowed`).
+5. `read_only` gate for mutating routes (`403 read_only`).
+6. Request body read/limit/JSON decode (`413 payload_too_large`, `400 bad_request`).
+7. Business validation and config write path.
+
+Notes:
+- Whitelist is evaluated against the direct TCP peer IP (`SocketAddr::ip`), without `X-Forwarded-For` support.
+- `Authorization` check is exact string equality against configured `auth_header`.
+
 ## Endpoint Matrix
 
 | Method | Path | Body | Success | `data` contract |
 | --- | --- | --- | --- | --- |
 | `GET` | `/v1/health` | none | `200` | `HealthData` |
+| `GET` | `/v1/system/info` | none | `200` | `SystemInfoData` |
+| `GET` | `/v1/runtime/gates` | none | `200` | `RuntimeGatesData` |
+| `GET` | `/v1/limits/effective` | none | `200` | `EffectiveLimitsData` |
+| `GET` | `/v1/security/posture` | none | `200` | `SecurityPostureData` |
+| `GET` | `/v1/security/whitelist` | none | `200` | `SecurityWhitelistData` |
 | `GET` | `/v1/stats/summary` | none | `200` | `SummaryData` |
 | `GET` | `/v1/stats/zero/all` | none | `200` | `ZeroAllData` |
+| `GET` | `/v1/stats/upstreams` | none | `200` | `UpstreamsData` |
 | `GET` | `/v1/stats/minimal/all` | none | `200` | `MinimalAllData` |
 | `GET` | `/v1/stats/me-writers` | none | `200` | `MeWritersData` |
 | `GET` | `/v1/stats/dcs` | none | `200` | `DcStatusData` |
+| `GET` | `/v1/runtime/me_pool_state` | none | `200` | `RuntimeMePoolStateData` |
+| `GET` | `/v1/runtime/me_quality` | none | `200` | `RuntimeMeQualityData` |
+| `GET` | `/v1/runtime/upstream_quality` | none | `200` | `RuntimeUpstreamQualityData` |
+| `GET` | `/v1/runtime/nat_stun` | none | `200` | `RuntimeNatStunData` |
+| `GET` | `/v1/runtime/connections/summary` | none | `200` | `RuntimeEdgeConnectionsSummaryData` |
+| `GET` | `/v1/runtime/events/recent` | none | `200` | `RuntimeEdgeEventsData` |
 | `GET` | `/v1/stats/users` | none | `200` | `UserInfo[]` |
 | `GET` | `/v1/users` | none | `200` | `UserInfo[]` |
 | `POST` | `/v1/users` | `CreateUserRequest` | `201` | `CreateUserResponse` |
 | `GET` | `/v1/users/{username}` | none | `200` | `UserInfo` |
 | `PATCH` | `/v1/users/{username}` | `PatchUserRequest` | `200` | `UserInfo` |
 | `DELETE` | `/v1/users/{username}` | none | `200` | `string` (deleted username) |
-| `POST` | `/v1/users/{username}/rotate-secret` | `RotateSecretRequest` or empty body | `200` | `CreateUserResponse` |
+| `POST` | `/v1/users/{username}/rotate-secret` | `RotateSecretRequest` or empty body | `404` | `ErrorResponse` (`not_found`, current runtime behavior) |
 
 ## Common Error Codes
 
@@ -77,8 +116,8 @@ API runtime is configured in `[server.api]`.
 | `401` | `unauthorized` | Missing/invalid `Authorization` when `auth_header` is configured. |
 | `403` | `forbidden` | Source IP is not allowed by whitelist. |
 | `403` | `read_only` | Mutating endpoint called while `read_only=true`. |
-| `404` | `not_found` | Unknown route or unknown user. |
-| `405` | `method_not_allowed` | Unsupported method for an existing user route. |
+| `404` | `not_found` | Unknown route, unknown user, or unsupported sub-route (including current `rotate-secret` route). |
+| `405` | `method_not_allowed` | Unsupported method for `/v1/users/{username}` route shape. |
 | `409` | `revision_conflict` | `If-Match` revision mismatch. |
 | `409` | `user_exists` | User already exists on create. |
 | `409` | `last_user_forbidden` | Attempt to delete last configured user. |
@@ -86,6 +125,28 @@ API runtime is configured in `[server.api]`.
 | `500` | `internal_error` | Internal error (I/O, serialization, config load/save). |
 | `503` | `api_disabled` | API disabled in config. |
 
+## Routing and Method Edge Cases
+
+| Case | Behavior |
+| --- | --- |
+| Path matching | Exact match on `req.uri().path()`. Query string does not affect route matching. |
+| Trailing slash | Not normalized. Example: `/v1/users/` is `404`. |
+| Username route with extra slash | `/v1/users/{username}/...` is not treated as user route and returns `404`. |
+| `PUT /v1/users/{username}` | `405 method_not_allowed`. |
+| `POST /v1/users/{username}` | `404 not_found`. |
+| `POST /v1/users/{username}/rotate-secret` | `404 not_found` in current release due route matcher limitation. |
+
+## Body and JSON Semantics
+
+- Request body is read only for mutating routes that define a body contract.
+- Body size limit is enforced during streaming read (`413 payload_too_large`).
+- Invalid transport body frame returns `400 bad_request` (`Invalid request body`).
+- Invalid JSON returns `400 bad_request` (`Invalid JSON body`).
+- `Content-Type` is not required for JSON parsing.
+- Unknown JSON fields are ignored by deserialization.
+- `PATCH` updates only provided fields and does not support explicit clearing of optional fields.
+- `If-Match` supports both quoted and unquoted values; surrounding whitespace is trimmed.
+
 ## Request Contracts
 
 ### `CreateUserRequest`
@@ -114,6 +175,8 @@ API runtime is configured in `[server.api]`.
 | --- | --- | --- | --- |
 | `secret` | `string` | no | Exactly 32 hex chars. If missing, generated automatically. |
 
+Note: the request contract is defined, but the corresponding route currently returns `404` (see routing edge cases).
+
 ## Response Data Contracts
 
 ### `HealthData`
@@ -131,6 +194,113 @@ API runtime is configured in `[server.api]`.
 | `handshake_timeouts_total` | `u64` | Handshake timeout count. |
 | `configured_users` | `usize` | Number of configured users in config. |
 
+### `SystemInfoData`
+| Field | Type | Description |
+| --- | --- | --- |
+| `version` | `string` | Binary version (`CARGO_PKG_VERSION`). |
+| `target_arch` | `string` | Target architecture (`std::env::consts::ARCH`). |
+| `target_os` | `string` | Target OS (`std::env::consts::OS`). |
+| `build_profile` | `string` | Build profile (`PROFILE` env when available). |
+| `git_commit` | `string?` | Optional commit hash from build env metadata. |
+| `build_time_utc` | `string?` | Optional build timestamp from build env metadata. |
+| `rustc_version` | `string?` | Optional compiler version from build env metadata. |
+| `process_started_at_epoch_secs` | `u64` | Process start time as Unix epoch seconds. |
+| `uptime_seconds` | `f64` | Process uptime in seconds. |
+| `config_path` | `string` | Active config file path used by runtime. |
+| `config_hash` | `string` | SHA-256 hash of current config content (same value as envelope `revision`). |
+| `config_reload_count` | `u64` | Number of successfully observed config updates since process start. |
+| `last_config_reload_epoch_secs` | `u64?` | Unix epoch seconds of the latest observed config reload; null/absent before first reload. |
+
+### `RuntimeGatesData`
+| Field | Type | Description |
+| --- | --- | --- |
+| `accepting_new_connections` | `bool` | Current admission-gate state for new listener accepts. |
+| `conditional_cast_enabled` | `bool` | Whether conditional ME admission logic is enabled (`general.use_middle_proxy`). |
+| `me_runtime_ready` | `bool` | Current ME runtime readiness status used for conditional gate decisions. |
+| `me2dc_fallback_enabled` | `bool` | Whether ME -> direct fallback is enabled. |
+| `use_middle_proxy` | `bool` | Current transport mode preference. |
+
+### `EffectiveLimitsData`
+| Field | Type | Description |
+| --- | --- | --- |
+| `update_every_secs` | `u64` | Effective unified updater interval. |
+| `me_reinit_every_secs` | `u64` | Effective ME periodic reinit interval. |
+| `me_pool_force_close_secs` | `u64` | Effective stale-writer force-close timeout. |
+| `timeouts` | `EffectiveTimeoutLimits` | Effective timeout policy snapshot. |
+| `upstream` | `EffectiveUpstreamLimits` | Effective upstream connect/retry limits. |
+| `middle_proxy` | `EffectiveMiddleProxyLimits` | Effective ME pool/floor/reconnect limits. |
+| `user_ip_policy` | `EffectiveUserIpPolicyLimits` | Effective unique-IP policy mode/window. |
+
+#### `EffectiveTimeoutLimits`
+| Field | Type | Description |
+| --- | --- | --- |
+| `client_handshake_secs` | `u64` | Client handshake timeout. |
+| `tg_connect_secs` | `u64` | Upstream Telegram connect timeout. |
+| `client_keepalive_secs` | `u64` | Client keepalive interval. |
+| `client_ack_secs` | `u64` | ACK timeout. |
+| `me_one_retry` | `u8` | Fast retry count for single-endpoint ME DC. |
+| `me_one_timeout_ms` | `u64` | Fast retry timeout per attempt for single-endpoint ME DC. |
+
+#### `EffectiveUpstreamLimits`
+| Field | Type | Description |
+| --- | --- | --- |
+| `connect_retry_attempts` | `u32` | Upstream connect retry attempts. |
+| `connect_retry_backoff_ms` | `u64` | Upstream retry backoff delay. |
+| `connect_budget_ms` | `u64` | Total connect wall-clock budget across retries. |
+| `unhealthy_fail_threshold` | `u32` | Consecutive fail threshold for unhealthy marking. |
+| `connect_failfast_hard_errors` | `bool` | Whether hard errors skip additional retries. |
+
+#### `EffectiveMiddleProxyLimits`
+| Field | Type | Description |
+| --- | --- | --- |
+| `floor_mode` | `string` | Effective floor mode (`static` or `adaptive`). |
+| `adaptive_floor_idle_secs` | `u64` | Adaptive floor idle threshold. |
+| `adaptive_floor_min_writers_single_endpoint` | `u8` | Adaptive floor minimum for single-endpoint DCs. |
+| `adaptive_floor_recover_grace_secs` | `u64` | Adaptive floor recovery grace period. |
+| `reconnect_max_concurrent_per_dc` | `u32` | Max concurrent reconnects per DC. |
+| `reconnect_backoff_base_ms` | `u64` | Reconnect base backoff. |
+| `reconnect_backoff_cap_ms` | `u64` | Reconnect backoff cap. |
+| `reconnect_fast_retry_count` | `u32` | Number of fast retries before standard backoff strategy. |
+| `me2dc_fallback` | `bool` | Effective ME -> direct fallback flag. |
+
+#### `EffectiveUserIpPolicyLimits`
+| Field | Type | Description |
+| --- | --- | --- |
+| `mode` | `string` | Unique-IP policy mode (`active_window`, `time_window`, `combined`). |
+| `window_secs` | `u64` | Time window length used by unique-IP policy. |
+
+### `SecurityPostureData`
+| Field | Type | Description |
+| --- | --- | --- |
+| `api_read_only` | `bool` | Current API read-only state. |
+| `api_whitelist_enabled` | `bool` | Whether whitelist filtering is active. |
+| `api_whitelist_entries` | `usize` | Number of configured whitelist CIDRs. |
+| `api_auth_header_enabled` | `bool` | Whether `Authorization` header validation is active. |
+| `proxy_protocol_enabled` | `bool` | Global PROXY protocol accept setting. |
+| `log_level` | `string` | Effective log level (`debug`, `verbose`, `normal`, `silent`). |
+| `telemetry_core_enabled` | `bool` | Core telemetry toggle. |
+| `telemetry_user_enabled` | `bool` | Per-user telemetry toggle. |
+| `telemetry_me_level` | `string` | ME telemetry level (`silent`, `normal`, `debug`). |
+
+### `SecurityWhitelistData`
+| Field | Type | Description |
+| --- | --- | --- |
+| `generated_at_epoch_secs` | `u64` | Snapshot generation timestamp. |
+| `enabled` | `bool` | `true` when whitelist has at least one CIDR entry. |
+| `entries_total` | `usize` | Number of whitelist CIDR entries. |
+| `entries` | `string[]` | Whitelist CIDR entries as strings. |
+
+### Runtime Min Endpoints
+- `/v1/runtime/me_pool_state`: generations, hardswap state, writer contour/health counts, refill inflight snapshot.
+- `/v1/runtime/me_quality`: ME error/drift/reconnect counters and per-DC RTT coverage snapshot.
+- `/v1/runtime/upstream_quality`: upstream runtime policy, connect counters, health summary and per-upstream DC latency/IP preference.
+- `/v1/runtime/nat_stun`: NAT/STUN runtime flags, server lists, reflection cache state and backoff remaining.
+
+### Runtime Edge Endpoints
+- `/v1/runtime/connections/summary`: cached connection totals (`total/me/direct`), active users and top-N users by connections/traffic.
+- `/v1/runtime/events/recent?limit=N`: bounded control-plane ring-buffer events (`limit` clamped to `[1, 1000]`).
+- If `server.api.runtime_edge_enabled=false`, runtime edge endpoints return `enabled=false` with `reason=feature_disabled`.
+
 ### `ZeroAllData`
 | Field | Type | Description |
 | --- | --- | --- |
@@ -173,6 +343,47 @@ API runtime is configured in `[server.api]`.
 | `connect_duration_fail_bucket_501_1000ms` | `u64` | Failed connects 501-1000 ms. |
 | `connect_duration_fail_bucket_gt_1000ms` | `u64` | Failed connects >1000 ms. |
 
+### `UpstreamsData`
+| Field | Type | Description |
+| --- | --- | --- |
+| `enabled` | `bool` | Runtime upstream snapshot availability according to API config. |
+| `reason` | `string?` | `feature_disabled` or `source_unavailable` when runtime snapshot is unavailable. |
+| `generated_at_epoch_secs` | `u64` | Snapshot generation time. |
+| `zero` | `ZeroUpstreamData` | Always available zero-cost upstream counters block. |
+| `summary` | `UpstreamSummaryData?` | Runtime upstream aggregate view, null when unavailable. |
+| `upstreams` | `UpstreamStatus[]?` | Per-upstream runtime status rows, null when unavailable. |
+
+#### `UpstreamSummaryData`
+| Field | Type | Description |
+| --- | --- | --- |
+| `configured_total` | `usize` | Total configured upstream entries. |
+| `healthy_total` | `usize` | Upstreams currently marked healthy. |
+| `unhealthy_total` | `usize` | Upstreams currently marked unhealthy. |
+| `direct_total` | `usize` | Number of direct upstream entries. |
+| `socks4_total` | `usize` | Number of SOCKS4 upstream entries. |
+| `socks5_total` | `usize` | Number of SOCKS5 upstream entries. |
+
+#### `UpstreamStatus`
+| Field | Type | Description |
+| --- | --- | --- |
+| `upstream_id` | `usize` | Runtime upstream index. |
+| `route_kind` | `string` | Upstream route kind: `direct`, `socks4`, `socks5`. |
+| `address` | `string` | Upstream address (`direct` for direct route kind). Authentication fields are intentionally omitted. |
+| `weight` | `u16` | Selection weight. |
+| `scopes` | `string` | Configured scope selector string. |
+| `healthy` | `bool` | Current health flag. |
+| `fails` | `u32` | Consecutive fail counter. |
+| `last_check_age_secs` | `u64` | Seconds since the last health-check update. |
+| `effective_latency_ms` | `f64?` | Effective upstream latency used by selector. |
+| `dc` | `UpstreamDcStatus[]` | Per-DC latency/IP preference snapshot. |
+
+#### `UpstreamDcStatus`
+| Field | Type | Description |
+| --- | --- | --- |
+| `dc` | `i16` | Telegram DC id. |
+| `latency_ema_ms` | `f64?` | Per-DC latency EMA value. |
+| `ip_preference` | `string` | Per-DC IP family preference: `unknown`, `prefer_v4`, `prefer_v6`, `both_work`, `unavailable`. |
+
 #### `ZeroMiddleProxyData`
 | Field | Type | Description |
 | --- | --- | --- |
@@ -392,8 +603,11 @@ API runtime is configured in `[server.api]`.
 
 Link generation uses active config and enabled modes:
 - `[general.links].public_host/public_port` have priority.
+- If `public_host` is not set, startup-detected public IPs are used (`IPv4`, `IPv6`, or both when available).
 - Fallback host sources: listener `announce`, `announce_ip`, explicit listener `ip`.
 - Legacy fallback: `listen_addr_ipv4` and `listen_addr_ipv6` when routable.
+- Startup-detected IPs are fixed for process lifetime and refreshed on restart.
+- User rows are sorted by `username` in ascending lexical order.
 
 ### `CreateUserResponse`
 | Field | Type | Description |
@@ -407,21 +621,53 @@ Link generation uses active config and enabled modes:
 | --- | --- |
 | `POST /v1/users` | Creates user and validates resulting config before atomic save. |
 | `PATCH /v1/users/{username}` | Partial update of provided fields only. Missing fields remain unchanged. |
-| `POST /v1/users/{username}/rotate-secret` | Replaces secret. Empty body is allowed and auto-generates secret. |
+| `POST /v1/users/{username}/rotate-secret` | Currently returns `404` in runtime route matcher; request schema is reserved for intended behavior. |
 | `DELETE /v1/users/{username}` | Deletes user and related optional settings. Last user deletion is blocked. |
 
 All mutating endpoints:
 - Respect `read_only` mode.
 - Accept optional `If-Match` for optimistic concurrency.
 - Return new `revision` after successful write.
+- Use process-local mutation lock + atomic write (`tmp + rename`) for config persistence.
+
+## Runtime State Matrix
+
+| Endpoint | `minimal_runtime_enabled=false` | `minimal_runtime_enabled=true` + source unavailable | `minimal_runtime_enabled=true` + source available |
+| --- | --- | --- | --- |
+| `/v1/stats/minimal/all` | `enabled=false`, `reason=feature_disabled`, `data=null` | `enabled=true`, `reason=source_unavailable`, fallback `data` with disabled ME blocks | `enabled=true`, `reason` omitted, full payload |
+| `/v1/stats/me-writers` | `middle_proxy_enabled=false`, `reason=feature_disabled` | `middle_proxy_enabled=false`, `reason=source_unavailable` | `middle_proxy_enabled=true`, runtime snapshot |
+| `/v1/stats/dcs` | `middle_proxy_enabled=false`, `reason=feature_disabled` | `middle_proxy_enabled=false`, `reason=source_unavailable` | `middle_proxy_enabled=true`, runtime snapshot |
+| `/v1/stats/upstreams` | `enabled=false`, `reason=feature_disabled`, `summary/upstreams` omitted, `zero` still present | `enabled=true`, `reason=source_unavailable`, `summary/upstreams` omitted, `zero` present | `enabled=true`, `reason` omitted, `summary/upstreams` present, `zero` present |
+
+`source_unavailable` conditions:
+- ME endpoints: ME pool is absent (for example direct-only mode or failed ME initialization).
+- Upstreams endpoint: non-blocking upstream snapshot lock is unavailable at request time.
+
+## Serialization Rules
+
+- Success responses always include `revision`.
+- Error responses never include `revision`; they include `request_id`.
+- Optional fields with `skip_serializing_if` are omitted when absent.
+- Nullable payload fields may still be `null` where contract uses `?` (for example `UserInfo` option fields).
+- For `/v1/stats/upstreams`, authentication details of SOCKS upstreams are intentionally omitted.
 
 ## Operational Notes
 
 | Topic | Details |
 | --- | --- |
-| API startup | API binds only when `[server.api].enabled=true`. |
-| Restart requirements | Changes in `server.api` settings require process restart. |
+| API startup | API listener is spawned only when `[server.api].enabled=true`. |
+| `listen` port `0` | API spawn is skipped when parsed listen port is `0` (treated as disabled bind target). |
+| Bind failure | Failed API bind logs warning and API task exits (no auto-retry loop). |
+| ME runtime status endpoints | `/v1/stats/me-writers`, `/v1/stats/dcs`, `/v1/stats/minimal/all` require `[server.api].minimal_runtime_enabled=true`; otherwise they return disabled payload with `reason=feature_disabled`. |
+| Upstream runtime endpoint | `/v1/stats/upstreams` always returns `zero`, but runtime fields (`summary`, `upstreams`) require `[server.api].minimal_runtime_enabled=true`. |
+| Restart requirements | `server.api` changes are restart-required for predictable behavior. |
+| Hot-reload nuance | A pure `server.api`-only config change may not propagate through watcher broadcast; a mixed change (with hot fields) may propagate API flags while still warning that restart is required. |
 | Runtime apply path | Successful writes are picked up by existing config watcher/hot-reload path. |
 | Exposure | Built-in TLS/mTLS is not provided. Use loopback bind + reverse proxy if needed. |
 | Pagination | User list currently has no pagination/filtering. |
 | Serialization side effect | Config comments/manual formatting are not preserved on write. |
+
+## Known Limitations (Current Release)
+
+- `POST /v1/users/{username}/rotate-secret` is currently unreachable in route matcher and returns `404`.
+- API runtime controls under `server.api` are documented as restart-required; hot-reload behavior for these fields is not strictly uniform in all change combinations.

docs/FAQ.en.md

@@ -0,0 +1,112 @@
+## How to set up "proxy sponsor" channel and statistics via @MTProxybot bot
+
+1. Go to @MTProxybot bot.
+2. Enter the command `/newproxy`
+3. Send the server IP and port. For example: 1.2.3.4:443
+4. Open the config `nano /etc/telemt.toml`.
+5. Copy and send the user secret from the [access.users] section to the bot.
+6. Copy the tag received from the bot. For example 1234567890abcdef1234567890abcdef.
+> [!WARNING]
+> The link provided by the bot will not work. Do not copy or use it!
+7. Uncomment the ad_tag parameter and enter the tag received from the bot.
+8. Uncomment/add the parameter `use_middle_proxy = true`.
+
+Config example:
+```toml
+[general]
+ad_tag = "1234567890abcdef1234567890abcdef"
+use_middle_proxy = true
+```
+9. Save the config. Ctrl+S -> Ctrl+X.
+10. Restart telemt `systemctl restart telemt`.
+11. In the bot, send the command /myproxies and select the added server.
+12. Click the "Set promotion" button.
+13. Send a **public link** to the channel. Private channels cannot be added!
+14. Wait approximately 1 hour for the information to update on Telegram servers.
+> [!WARNING]
+> You will not see the "proxy sponsor" if you are already subscribed to the channel.
+
+**You can also set up different channels for different users.**
+```toml
+[access.user_ad_tags]
+hello = "ad_tag"
+hello2 = "ad_tag2"
+```
+
+## How many people can use 1 link
+
+By default, 1 link can be used by any number of people.  
+You can limit the number of IPs using the proxy.
+```toml
+[access.user_max_unique_ips]
+hello = 1
+```
+This parameter limits how many unique IPs can use 1 link simultaneously. If one user disconnects, a second user can connect. Also, multiple users can sit behind the same IP.
+
+## How to create multiple different links
+
+1. Generate the required number of secrets `openssl rand -hex 16`
+2. Open the config `nano /etc/telemt.toml`
+3. Add new users.
+```toml
+[access.users]
+user1 = "00000000000000000000000000000001"
+user2 = "00000000000000000000000000000002"
+user3 = "00000000000000000000000000000003"
+```
+4. Save the config. Ctrl+S -> Ctrl+X. You don't need to restart telemt.
+5. Get the links via `journalctl -u telemt -n -g "links" --no-pager -o cat | tac`
+
+## How to view metrics
+
+1. Open the config `nano /etc/telemt.toml`
+2. Add the following parameters
+```toml
+[server]
+metrics_port = 9090
+metrics_whitelist = ["127.0.0.1/32", "::1/128", "0.0.0.0/0"]
+```
+3. Save the config. Ctrl+S -> Ctrl+X.
+4. Metrics are available at SERVER_IP:9090/metrics.
+> [!WARNING]
+> "0.0.0.0/0" in metrics_whitelist opens access from any IP. Replace with your own IP. For example "1.2.3.4"
+
+## Additional parameters
+
+### Domain in link instead of IP
+To specify a domain in the links, add to the `[general.links]` section of the config file.
+```toml
+[general.links]
+public_host = "proxy.example.com"
+```
+
+### Upstream Manager
+To specify an upstream, add to the `[[upstreams]]` section of the config.toml file:
+#### Binding to IP
+```toml
+[[upstreams]]
+type = "direct"
+weight = 1
+enabled = true
+interface = "192.168.1.100" # Change to your outgoing IP
+```
+#### SOCKS4/5 as Upstream
+- Without authentication:
+```toml
+[[upstreams]]
+type = "socks5"            # Specify SOCKS4 or SOCKS5
+address = "1.2.3.4:1234"   # SOCKS-server Address
+weight = 1                 # Set Weight for Scenarios
+enabled = true
+```
+
+- With authentication:
+```toml
+[[upstreams]]
+type = "socks5"            # Specify SOCKS4 or SOCKS5
+address = "1.2.3.4:1234"   # SOCKS-server Address
+username = "user"          # Username for Auth on SOCKS-server
+password = "pass"          # Password for Auth on SOCKS-server
+weight = 1                 # Set Weight for Scenarios
+enabled = true
+```

docs/FAQ.ru.md

@@ -1,4 +1,4 @@
-## Как настроить канал "спонсор прокси"
+## Как настроить канал "спонсор прокси" и статистику через бота @MTProxybot
 
 1. Зайти в бота @MTProxybot.
 2. Ввести команду `/newproxy`
@@ -26,6 +26,13 @@ use_middle_proxy = true
 > [!WARNING]
 > У вас не будет отображаться "спонсор прокси" если вы уже подписаны на канал.
 
+**Также вы можете настроить разные каналы для разных пользователей.**
+```toml
+[access.user_ad_tags]
+hello = "ad_tag"
+hello2 = "ad_tag2"
+```
+
 ## Сколько человек может пользоваться 1 ссылкой
 
 По умолчанию 1 ссылкой может пользоваться сколько угодно человек.  
@@ -63,3 +70,43 @@ metrics_whitelist = ["127.0.0.1/32", "::1/128", "0.0.0.0/0"]
 4. Метрики доступны по адресу SERVER_IP:9090/metrics. 
 > [!WARNING]
 > "0.0.0.0/0" в metrics_whitelist открывает доступ с любого IP. Замените на свой ip. Например "1.2.3.4"
+
+## Дополнительные параметры
+
+### Домен в ссылке вместо IP
+Чтобы указать домен в ссылках, добавьте в секцию `[general.links]` файла config.
+```toml
+[general.links]
+public_host = "proxy.example.com"
+```
+
+### Upstream Manager
+Чтобы указать апстрим, добавьте в секцию `[[upstreams]]` файла config.toml:
+#### Привязка к IP
+```toml
+[[upstreams]]
+type = "direct"
+weight = 1
+enabled = true
+interface = "192.168.1.100" # Change to your outgoing IP
+```
+#### SOCKS4/5 как Upstream
+- Без авторизации:
+```toml
+[[upstreams]]
+type = "socks5"            # Specify SOCKS4 or SOCKS5
+address = "1.2.3.4:1234"   # SOCKS-server Address
+weight = 1                 # Set Weight for Scenarios
+enabled = true
+```
+
+- С авторизацией:
+```toml
+[[upstreams]]
+type = "socks5"            # Specify SOCKS4 or SOCKS5
+address = "1.2.3.4:1234"   # SOCKS-server Address
+username = "user"          # Username for Auth on SOCKS-server
+password = "pass"          # Password for Auth on SOCKS-server
+weight = 1                 # Set Weight for Scenarios
+enabled = true
+```

docs/QUICK_START_GUIDE.en.md

@@ -60,12 +60,19 @@ paste your config
 # === General Settings ===
 [general]
 # ad_tag = "00000000000000000000000000000000"
+use_middle_proxy = false
 
 [general.modes]
 classic = false
 secure = false
 tls = true
 
+[server.api]
+enabled = true
+# listen = "127.0.0.1:9091"
+# whitelist = ["127.0.0.1/32"]
+# read_only = true
+
 # === Anti-Censorship & Masking ===
 [censorship]
 tls_domain = "petrovich.ru"
@@ -74,6 +81,7 @@ tls_domain = "petrovich.ru"
 # format: "username" = "32_hex_chars_secret"
 hello = "00000000000000000000000000000000"
 ```
+
 then Ctrl+S -> Ctrl+X to save
 
 > [!WARNING]
@@ -114,7 +122,12 @@ then Ctrl+S -> Ctrl+X to save
 
 **5.** For automatic startup at system boot, enter `systemctl enable telemt`
 
-**6.** To get the links, enter `journalctl -u telemt -n -g "links" --no-pager -o cat | tac`
+**6.** To get the link(s), enter
+```bash
+curl -s http://127.0.0.1:9091/v1/users | jq
+```
+
+> Any number of people can use one link.
 
 ---
 

docs/QUICK_START_GUIDE.ru.md

@@ -60,12 +60,19 @@ nano /etc/telemt.toml
 # === General Settings ===
 [general]
 # ad_tag = "00000000000000000000000000000000"
+use_middle_proxy = false
 
 [general.modes]
 classic = false
 secure = false
 tls = true
 
+[server.api]
+enabled = true
+# listen = "127.0.0.1:9091"
+# whitelist = ["127.0.0.1/32"]
+# read_only = true
+
 # === Anti-Censorship & Masking ===
 [censorship]
 tls_domain = "petrovich.ru"
@@ -74,6 +81,7 @@ tls_domain = "petrovich.ru"
 # format: "username" = "32_hex_chars_secret"
 hello = "00000000000000000000000000000000"
 ```
+
 Затем нажмите Ctrl+S -> Ctrl+X, чтобы сохранить
 
 > [!WARNING]
@@ -114,9 +122,14 @@ WantedBy=multi-user.target
 
 **5.** Для автоматического запуска при запуске системы в введите `systemctl enable telemt`
 
-**6.** Для получения ссылки введите `journalctl -u telemt -n -g "links" --no-pager -o cat | tac`
+**6.** Для получения ссылки/ссылок введите 
+```bash
+curl -s http://127.0.0.1:9091/v1/users | jq
+```
+> Одной ссылкой может пользоваться сколько угодно человек.
+
 > [!WARNING]
-> Рабочую ссылку может выдать только команда из 6 пункта. Не пытайтесь делать ее самостоятельно или копировать откуда-либо!
+> Рабочую ссылку может выдать только команда из 6 пункта. Не пытайтесь делать ее самостоятельно или копировать откуда-либо если вы не уверены в том, что делаете!
 
 ---
 

docs/model/MODEL.en.md

@@ -0,0 +1,285 @@
+# Telemt Runtime Model
+
+## Scope
+This document defines runtime concepts used by the Middle-End (ME) transport pipeline and the orchestration logic around it.
+
+It focuses on:
+- `ME Pool / Reader / Writer / Refill / Registry`
+- `Adaptive Floor`
+- `Trio-State`
+- `Generation Lifecycle`
+
+## Core Entities
+
+### ME Pool
+`ME Pool` is the runtime orchestrator for all Middle-End writers.
+
+Responsibilities:
+- Holds writer inventory by DC/family/endpoint.
+- Maintains routing primitives and writer selection policy.
+- Tracks generation state (`active`, `warm`, `draining` context).
+- Applies runtime policies (floor mode, refill, reconnect, reinit, fallback behavior).
+- Exposes readiness gates used by admission logic (for conditional accept/cast behavior).
+
+Non-goals:
+- It does not own client protocol decoding.
+- It does not own per-client business policy (quotas/limits).
+
+### ME Writer
+`ME Writer` is a long-lived ME RPC tunnel bound to one concrete ME endpoint (`ip:port`), with:
+- Outbound command channel (send path).
+- Associated reader loop (inbound path).
+- Health/degraded flags.
+- Contour/state and generation metadata.
+
+A writer is the actual data plane carrier for client sessions once bound.
+
+### ME Reader
+`ME Reader` is the inbound parser/dispatcher for one writer:
+- Reads/decrypts ME RPC frames.
+- Validates sequence/checksum.
+- Routes payloads to client-connection channels via `Registry`.
+- Emits close/ack/data events and updates telemetry.
+
+Design intent:
+- Reader must stay non-blocking as much as possible.
+- Backpressure on a single client route must not stall the whole writer stream.
+
+### Refill
+`Refill` is the recovery mechanism that restores writer coverage when capacity drops:
+- Per-endpoint restore (same endpoint first).
+- Per-DC restore to satisfy required floor.
+- Optional outage-mode/shadow behavior for fragile single-endpoint DCs.
+
+Refill works asynchronously and should not block hot routing paths.
+
+### Registry
+`Registry` is the routing index between ME and client sessions:
+- `conn_id -> client response channel`
+- `conn_id <-> writer_id` binding map
+- writer activity snapshots and idle tracking
+
+Main invariants:
+- A `conn_id` routes to at most one active response channel.
+- Writer loss triggers safe unbind/cleanup and close propagation.
+- Registry state is the source of truth for active ME-bound session mapping.
+
+## Adaptive Floor
+
+### What it is
+`Adaptive Floor` is a runtime policy that changes target writer count per DC based on observed activity, instead of always holding static peak floor.
+
+### Why it exists
+Goals:
+- Reduce idle writer churn under low traffic.
+- Keep enough warm capacity to avoid client-visible stalls on burst recovery.
+- Limit needless reconnect storms on unstable endpoints.
+
+### Behavioral model
+- Under activity: floor converges toward configured static requirement.
+- Under prolonged idle: floor can shrink to a safe minimum.
+- Recovery/grace windows prevent aggressive oscillation.
+
+### Safety constraints
+- Never violate minimal survivability floor for a DC group.
+- Refill must still restore quickly on demand.
+- Floor adaptation must not force-drop already bound healthy sessions.
+
+## Trio-State
+
+`Trio-State` is writer contouring:
+- `Warm`
+- `Active`
+- `Draining`
+
+### State semantics
+- `Warm`: connected and validated, not primary for new binds.
+- `Active`: preferred for new binds and normal traffic.
+- `Draining`: no new regular binds; existing sessions continue until graceful retirement rules apply.
+
+### Transition intent
+- `Warm -> Active`: when coverage/readiness conditions are satisfied.
+- `Active -> Draining`: on generation swap, endpoint replacement, or controlled retirement.
+- `Draining -> removed`: after drain TTL/force-close policy (or when naturally empty).
+
+This separation reduces SPOF and keeps cutovers predictable.
+
+## Generation Lifecycle
+
+Generation isolates pool epochs during reinit/reconfiguration.
+
+### Lifecycle phases
+1. `Bootstrap`: initial writers are established.
+2. `Warmup`: next generation writers are created and validated.
+3. `Activation`: generation promoted to active when coverage gate passes.
+4. `Drain`: previous generation becomes draining, existing sessions are allowed to finish.
+5. `Retire`: old generation writers are removed after graceful rules.
+
+### Operational guarantees
+- No partial generation activation without minimum coverage.
+- Existing healthy client sessions should not be dropped just because a new generation appears.
+- Draining generation exists to absorb in-flight traffic during swap.
+
+### Readiness and admission
+Pool readiness is not equivalent to “all endpoints fully saturated”.
+Typical gating strategy:
+- Open admission when per-DC minimal alive coverage exists.
+- Continue background saturation for multi-endpoint DCs.
+
+This keeps startup latency low while preserving eventual full capacity.
+
+## Interactions Between Concepts
+
+- `Generation` defines pool epochs.
+- `Trio-State` defines per-writer role inside/around those epochs.
+- `Adaptive Floor` defines how much capacity should be maintained right now.
+- `Refill` is the actuator that closes the gap between desired and current capacity.
+- `Registry` keeps per-session routing correctness while all of the above changes over time.
+
+## Architectural Approach
+
+### Layered Design
+The runtime is intentionally split into two planes:
+- `Control Plane`: decides desired topology and policy (`floor`, `generation swap`, `refill`, `fallback`).
+- `Data Plane`: executes packet/session transport (`reader`, `writer`, routing, acks, close propagation).
+
+Architectural rule:
+- Control Plane may change writer inventory and policy.
+- Data Plane must remain stable and low-latency while those changes happen.
+
+### Ownership Model
+Ownership is centered around explicit state domains:
+- `MePool` owns writer lifecycle and policy state.
+- `Registry` owns per-connection routing bindings.
+- `Writer task` owns outbound ME socket send progression.
+- `Reader task` owns inbound ME socket parsing and event dispatch.
+
+This prevents accidental cross-layer mutation and keeps invariants local.
+
+### Control Plane Responsibilities
+Control Plane is event-driven and policy-driven:
+- Startup initialization and readiness gates.
+- Runtime reinit (periodic or config-triggered).
+- Coverage checks per DC/family/endpoint group.
+- Floor enforcement (static/adaptive).
+- Refill scheduling and retry orchestration.
+- Generation transition (`warm -> active`, previous `active -> draining`).
+
+Control Plane must prioritize determinism over short-term aggressiveness.
+
+### Data Plane Responsibilities
+Data Plane is throughput-first and allocation-sensitive:
+- Session bind to writer.
+- Per-frame parsing/validation and dispatch.
+- Ack and close signal propagation.
+- Route drop behavior under missing connection or closed channel.
+- Minimal critical logging in hot path.
+
+Data Plane should avoid waiting on operations that are not strictly required for frame correctness.
+
+## Concurrency and Synchronization
+
+### Concurrency Principles
+- Per-writer isolation: each writer has independent send/read task loops.
+- Per-connection isolation: client channel state is scoped by `conn_id`.
+- Asynchronous recovery: refill/reconnect runs outside the packet hot path.
+
+### Synchronization Strategy
+- Shared maps use fine-grained, short-lived locking.
+- Read-mostly paths avoid broad write-lock windows.
+- Backpressure decisions are localized at route/channel boundary.
+
+Design target:
+- A slow consumer should degrade only itself (or its route), not global writer progress.
+
+### Cancellation and Shutdown
+Writer and reader loops are cancellation-aware:
+- explicit cancel token / close command support;
+- safe unbind and cleanup via registry;
+- deterministic order: stop admission -> drain/close -> release resources.
+
+## Consistency Model
+
+### Session Consistency
+For one `conn_id`:
+- exactly one active route target at a time;
+- close and unbind must be idempotent;
+- writer loss must not leave dangling bindings.
+
+### Generation Consistency
+Generational consistency guarantees:
+- New generation is not promoted before minimum coverage gate.
+- Previous generation remains available in `draining` state during handover.
+- Forced retirement is policy-bound (`drain ttl`, optional force-close), not immediate.
+
+### Policy Consistency
+Policy changes (`adaptive/static floor`, fallback mode, retries) should apply without violating established active-session routing invariants.
+
+## Backpressure and Flow Control
+
+### Route-Level Backpressure
+Route channels are bounded by design.
+When pressure increases:
+- short burst absorption is allowed;
+- prolonged congestion triggers controlled drop semantics;
+- drop accounting is explicit via metrics/counters.
+
+### Reader Non-Blocking Priority
+Inbound ME reader path should never be serialized behind one congested client route.
+Practical implication:
+- prefer non-blocking route attempt in the parser loop;
+- move heavy recovery to async side paths.
+
+## Failure Domain Strategy
+
+### Endpoint-Level Failure
+Failure of one endpoint should trigger endpoint-scoped recovery first:
+- same endpoint reconnect;
+- endpoint replacement within same DC group if applicable.
+
+### DC-Level Degradation
+If a DC group cannot satisfy floor:
+- keep service via remaining coverage if policy allows;
+- continue asynchronous refill saturation in background.
+
+### Whole-Pool Readiness Loss
+If no sufficient ME coverage exists:
+- admission gate can hold new accepts (conditional policy);
+- existing sessions should continue when their path remains healthy.
+
+## Performance Architecture Notes
+
+### Hotpath Discipline
+Allowed in hotpath:
+- fixed-size parsing and cheap validation;
+- bounded channel operations;
+- precomputed or low-allocation access patterns.
+
+Avoid in hotpath:
+- repeated expensive decoding;
+- broad locks with awaits inside critical sections;
+- verbose high-frequency logging.
+
+### Throughput Stability Over Peak Spikes
+Architecture prefers stable throughput and predictable latency over short peak gains that increase churn or long-tail reconnect times.
+
+## Evolution and Extension Rules
+
+To evolve this model safely:
+- Add new policy knobs in Control Plane first.
+- Keep Data Plane contracts stable (`conn_id`, route semantics, close semantics).
+- Validate generation and registry invariants before enabling by default.
+- Introduce new retry/recovery strategies behind explicit config.
+
+## Failure and Recovery Notes
+
+- Single-endpoint DC failure is a normal degraded mode case; policy should prioritize fast reconnect and optional shadow/probing strategies.
+- Idle close by peer should be treated as expected when upstream enforces idle timeout.
+- Reconnect backoff must protect against synchronized churn while still allowing fast first retries.
+- Fallback (`ME -> direct DC`) is a policy switch, not a transport bug by itself.
+
+## Terminology Summary
+- `Coverage`: enough live writers to satisfy per-DC acceptance policy.
+- `Floor`: target minimum writer count policy.
+- `Churn`: frequent writer reconnect/remove cycles.
+- `Hotpath`: per-packet/per-connection data path where extra waits/allocations are expensive.

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+# Runtime-модель Telemt
+
+## Область описания
+Документ фиксирует ключевые runtime-понятия пайплайна Middle-End (ME) и оркестрации вокруг него.
+
+Фокус:
+- `ME Pool / Reader / Writer / Refill / Registry`
+- `Adaptive Floor`
+- `Trio-State`
+- `Generation Lifecycle`
+
+## Базовые сущности
+
+### ME Pool
+`ME Pool` — центральный оркестратор всех Middle-End writer-ов.
+
+Зона ответственности:
+- хранит инвентарь writer-ов по DC/family/endpoint;
+- управляет выбором writer-а и маршрутизацией;
+- ведёт состояние поколений (`active`, `warm`, `draining` контекст);
+- применяет runtime-политики (floor, refill, reconnect, reinit, fallback);
+- отдаёт сигналы готовности для admission-логики (conditional accept/cast).
+
+Что не делает:
+- не декодирует клиентский протокол;
+- не реализует бизнес-политику пользователя (квоты/лимиты).
+
+### ME Writer
+`ME Writer` — долгоживущий ME RPC-канал к конкретному endpoint (`ip:port`), у которого есть:
+- канал команд на отправку;
+- связанный reader loop для входящего потока;
+- флаги состояния/деградации;
+- метаданные contour/state и generation.
+
+Writer — это фактический data-plane носитель клиентских сессий после бинда.
+
+### ME Reader
+`ME Reader` — входной parser/dispatcher одного writer-а:
+- читает и расшифровывает ME RPC-фреймы;
+- проверяет sequence/checksum;
+- маршрутизирует payload в client-каналы через `Registry`;
+- обрабатывает close/ack/data и обновляет телеметрию.
+
+Инженерный принцип:
+- Reader должен оставаться неблокирующим.
+- Backpressure одной клиентской сессии не должен останавливать весь поток writer-а.
+
+### Refill
+`Refill` — механизм восстановления покрытия writer-ов при просадке:
+- восстановление на том же endpoint в первую очередь;
+- восстановление по DC до требуемого floor;
+- опциональные outage/shadow-режимы для хрупких single-endpoint DC.
+
+Refill работает асинхронно и не должен блокировать hotpath.
+
+### Registry
+`Registry` — маршрутизационный индекс между ME и клиентскими сессиями:
+- `conn_id -> канал ответа клиенту`;
+- map биндов `conn_id <-> writer_id`;
+- снимки активности writer-ов и idle-трекинг.
+
+Ключевые инварианты:
+- один `conn_id` маршрутизируется максимум в один активный канал ответа;
+- потеря writer-а приводит к безопасному unbind/cleanup и отправке close;
+- именно `Registry` является источником истины по активным ME-биндам.
+
+## Adaptive Floor
+
+### Что это
+`Adaptive Floor` — runtime-политика, которая динамически меняет целевое число writer-ов на DC в зависимости от активности, а не держит всегда фиксированный статический floor.
+
+### Зачем
+Цели:
+- уменьшить churn на idle-трафике;
+- сохранить достаточную прогретую ёмкость для быстрых всплесков;
+- снизить лишние reconnect-штормы на нестабильных endpoint.
+
+### Модель поведения
+- при активности floor стремится к статическому требованию;
+- при длительном idle floor может снижаться до безопасного минимума;
+- grace/recovery окна не дают системе "флапать" слишком резко.
+
+### Ограничения безопасности
+- нельзя нарушать минимальный floor выживаемости DC-группы;
+- refill обязан быстро нарастить покрытие по запросу;
+- адаптация не должна принудительно ронять уже привязанные healthy-сессии.
+
+## Trio-State
+
+`Trio-State` — контурная роль writer-а:
+- `Warm`
+- `Active`
+- `Draining`
+
+### Семантика состояний
+- `Warm`: writer подключён и валиден, но не основной для новых биндов.
+- `Active`: приоритетный для новых биндов и обычного трафика.
+- `Draining`: новые обычные бинды не назначаются; текущие сессии живут до правил graceful-вывода.
+
+### Логика переходов
+- `Warm -> Active`: когда достигнуты условия покрытия/готовности.
+- `Active -> Draining`: при swap поколения, замене endpoint или контролируемом выводе.
+- `Draining -> removed`: после drain TTL/force-close политики (или естественного опустошения).
+
+Такое разделение снижает SPOF-риски и делает cutover предсказуемым.
+
+## Generation Lifecycle
+
+Generation изолирует эпохи пула при reinit/reconfiguration.
+
+### Фазы жизненного цикла
+1. `Bootstrap`: поднимается начальный набор writer-ов.
+2. `Warmup`: создаётся и валидируется новое поколение.
+3. `Activation`: новое поколение становится active после прохождения coverage-gate.
+4. `Drain`: предыдущее поколение переводится в draining, текущим сессиям дают завершиться.
+5. `Retire`: старое поколение удаляется по graceful-правилам.
+
+### Операционные гарантии
+- нельзя активировать поколение частично без минимального покрытия;
+- healthy-клиенты не должны теряться только из-за появления нового поколения;
+- draining-поколение служит буфером для in-flight трафика во время swap.
+
+### Готовность и приём клиентов
+Готовность пула не равна "все endpoint полностью насыщены".
+Типичная стратегия:
+- открыть admission при минимально достаточном alive-покрытии по DC;
+- параллельно продолжать saturation для multi-endpoint DC.
+
+Это уменьшает startup latency и сохраняет выход на полную ёмкость.
+
+## Как понятия связаны между собой
+
+- `Generation` задаёт эпохи пула.
+- `Trio-State` задаёт роль каждого writer-а внутри/между эпохами.
+- `Adaptive Floor` задаёт, сколько ёмкости нужно сейчас.
+- `Refill` — исполнитель, который закрывает разницу между desired и current capacity.
+- `Registry` гарантирует корректную маршрутизацию сессий, пока всё выше меняется.
+
+## Архитектурный подход
+
+### Слоистая модель
+Runtime специально разделён на две плоскости:
+- `Control Plane`: принимает решения о целевой топологии и политиках (`floor`, `generation swap`, `refill`, `fallback`).
+- `Data Plane`: исполняет транспорт сессий и пакетов (`reader`, `writer`, маршрутизация, ack, close).
+
+Ключевое правило:
+- Control Plane может менять состав writer-ов и policy.
+- Data Plane должен оставаться стабильным и низколатентным в момент этих изменений.
+
+### Модель владения состоянием
+Владение разделено по доменам:
+- `MePool` владеет жизненным циклом writer-ов и policy-state.
+- `Registry` владеет routing-биндами клиентских сессий.
+- `Writer task` владеет исходящей прогрессией ME-сокета.
+- `Reader task` владеет входящим парсингом и dispatch-событиями.
+
+Это ограничивает побочные мутации и локализует инварианты.
+
+### Обязанности Control Plane
+Control Plane работает событийно и policy-ориентированно:
+- стартовая инициализация и readiness-gate;
+- runtime reinit (периодический и/или по изменению конфигурации);
+- проверки покрытия по DC/family/endpoint group;
+- применение floor-политики (static/adaptive);
+- планирование refill и orchestration retry;
+- переходы поколений (`warm -> active`, прежний `active -> draining`).
+
+Для него важнее детерминизм, чем агрессивная краткосрочная реакция.
+
+### Обязанности Data Plane
+Data Plane ориентирован на пропускную способность и предсказуемую задержку:
+- bind клиентской сессии к writer-у;
+- per-frame parsing/validation/dispatch;
+- распространение ack/close;
+- корректная реакция на missing conn/closed channel;
+- минимальный лог-шум в hotpath.
+
+Data Plane не должен ждать операций, не критичных для корректности текущего фрейма.
+
+## Конкурентность и синхронизация
+
+### Принципы конкурентности
+- Изоляция по writer-у: у каждого writer-а независимые send/read loop.
+- Изоляция по сессии: состояние канала локально для `conn_id`.
+- Асинхронное восстановление: refill/reconnect выполняются вне пакетного hotpath.
+
+### Стратегия синхронизации
+- Для shared map используются короткие и узкие lock-секции.
+- Read-heavy пути избегают длительных write-lock окон.
+- Решения по backpressure локализованы на границе route/channel.
+
+Цель:
+- медленный consumer должен деградировать локально, не останавливая глобальный прогресс writer-а.
+
+### Cancellation и shutdown
+Reader/Writer loop должны быть cancellation-aware:
+- явные cancel token / close command;
+- безопасный unbind/cleanup через registry;
+- детерминированный порядок: stop admission -> drain/close -> release resources.
+
+## Модель согласованности
+
+### Согласованность сессии
+Для одного `conn_id`:
+- одновременно ровно один активный route-target;
+- close/unbind операции идемпотентны;
+- потеря writer-а не оставляет dangling-бинды.
+
+### Согласованность поколения
+Гарантии generation:
+- новое поколение не активируется до прохождения минимального coverage-gate;
+- предыдущее поколение остаётся в `draining` на время handover;
+- принудительный вывод writer-ов ограничен policy (`drain ttl`, optional force-close), а не мгновенный.
+
+### Согласованность политик
+Изменение policy (`adaptive/static floor`, fallback mode, retries) не должно ломать инварианты маршрутизации уже активных сессий.
+
+## Backpressure и управление потоком
+
+### Route-level backpressure
+Route-каналы намеренно bounded.
+При росте нагрузки:
+- кратковременный burst поглощается;
+- длительная перегрузка переходит в контролируемую drop-семантику;
+- все drop-сценарии должны быть прозрачно видны в метриках.
+
+### Приоритет неблокирующего Reader
+Входящий ME-reader path не должен сериализоваться из-за одной перегруженной клиентской сессии.
+Практически это означает:
+- использовать неблокирующую попытку route в parser loop;
+- выносить тяжёлое восстановление в асинхронные side-path.
+
+## Стратегия доменов отказа
+
+### Отказ отдельного endpoint
+Сначала применяется endpoint-local recovery:
+- reconnect в тот же endpoint;
+- затем замена endpoint внутри той же DC-группы (если доступно).
+
+### Деградация уровня DC
+Если DC-группа не набирает floor:
+- сервис сохраняется на остаточном покрытии (если policy разрешает);
+- saturation refill продолжается асинхронно в фоне.
+
+### Потеря готовности всего пула
+Если достаточного ME-покрытия нет:
+- admission gate может временно закрыть приём новых подключений (conditional policy);
+- уже активные сессии продолжают работать, пока их маршрут остаётся healthy.
+
+## Архитектурные заметки по производительности
+
+### Дисциплина hotpath
+Допустимо в hotpath:
+- фиксированный и дешёвый parsing/validation;
+- bounded channel operations;
+- precomputed/low-allocation доступ к данным.
+
+Нежелательно в hotpath:
+- повторные дорогие decode;
+- широкие lock-секции с `await` внутри;
+- высокочастотный подробный logging.
+
+### Стабильность важнее пиков
+Архитектура приоритетно выбирает стабильную пропускную способность и предсказуемую latency, а не краткосрочные пики ценой churn и long-tail reconnect.
+
+## Правила эволюции модели
+
+Чтобы расширять модель безопасно:
+- новые policy knobs сначала внедрять в Control Plane;
+- контракты Data Plane (`conn_id`, route/close семантика) держать стабильными;
+- перед дефолтным включением проверять generation/registry инварианты;
+- новые recovery/retry стратегии вводить через явный config-флаг.
+
+## Нюансы отказов и восстановления
+
+- падение single-endpoint DC — штатный деградированный сценарий; приоритет: быстрый reconnect и, при необходимости, shadow/probing;
+- idle-close со стороны peer должен считаться нормальным событием при upstream idle-timeout;
+- backoff reconnect-логики должен ограничивать синхронный churn, но сохранять быстрые первые попытки;
+- fallback (`ME -> direct DC`) — это переключаемая policy-ветка, а не автоматический признак бага транспорта.
+
+## Краткий словарь
+- `Coverage`: достаточное число живых writer-ов для политики приёма по DC.
+- `Floor`: целевая минимальная ёмкость writer-ов.
+- `Churn`: частые циклы reconnect/remove writer-ов.
+- `Hotpath`: пер-пакетный/пер-коннектный путь, где любые лишние ожидания и аллокации особенно дороги.

src/api/events.rs

@@ -0,0 +1,90 @@
+use std::collections::VecDeque;
+use std::sync::Mutex;
+use std::time::{SystemTime, UNIX_EPOCH};
+
+use serde::Serialize;
+
+#[derive(Clone, Serialize)]
+pub(super) struct ApiEventRecord {
+    pub(super) seq: u64,
+    pub(super) ts_epoch_secs: u64,
+    pub(super) event_type: String,
+    pub(super) context: String,
+}
+
+#[derive(Clone, Serialize)]
+pub(super) struct ApiEventSnapshot {
+    pub(super) capacity: usize,
+    pub(super) dropped_total: u64,
+    pub(super) events: Vec<ApiEventRecord>,
+}
+
+struct ApiEventsInner {
+    capacity: usize,
+    dropped_total: u64,
+    next_seq: u64,
+    events: VecDeque<ApiEventRecord>,
+}
+
+/// Bounded ring-buffer for control-plane API/runtime events.
+pub(crate) struct ApiEventStore {
+    inner: Mutex<ApiEventsInner>,
+}
+
+impl ApiEventStore {
+    pub(super) fn new(capacity: usize) -> Self {
+        let bounded = capacity.max(16);
+        Self {
+            inner: Mutex::new(ApiEventsInner {
+                capacity: bounded,
+                dropped_total: 0,
+                next_seq: 1,
+                events: VecDeque::with_capacity(bounded),
+            }),
+        }
+    }
+
+    pub(super) fn record(&self, event_type: &str, context: impl Into<String>) {
+        let now_epoch_secs = SystemTime::now()
+            .duration_since(UNIX_EPOCH)
+            .unwrap_or_default()
+            .as_secs();
+        let mut context = context.into();
+        if context.len() > 256 {
+            context.truncate(256);
+        }
+
+        let mut guard = self.inner.lock().expect("api event store mutex poisoned");
+        if guard.events.len() == guard.capacity {
+            guard.events.pop_front();
+            guard.dropped_total = guard.dropped_total.saturating_add(1);
+        }
+        let seq = guard.next_seq;
+        guard.next_seq = guard.next_seq.saturating_add(1);
+        guard.events.push_back(ApiEventRecord {
+            seq,
+            ts_epoch_secs: now_epoch_secs,
+            event_type: event_type.to_string(),
+            context,
+        });
+    }
+
+    pub(super) fn snapshot(&self, limit: usize) -> ApiEventSnapshot {
+        let guard = self.inner.lock().expect("api event store mutex poisoned");
+        let bounded_limit = limit.clamp(1, guard.capacity.max(1));
+        let mut items: Vec<ApiEventRecord> = guard
+            .events
+            .iter()
+            .rev()
+            .take(bounded_limit)
+            .cloned()
+            .collect();
+        items.reverse();
+
+        ApiEventSnapshot {
+            capacity: guard.capacity,
+            dropped_total: guard.dropped_total,
+            events: items,
+        }
+    }
+}

src/api/http_utils.rs

@@ -0,0 +1,91 @@
+use http_body_util::{BodyExt, Full};
+use hyper::StatusCode;
+use hyper::body::{Bytes, Incoming};
+use serde::Serialize;
+use serde::de::DeserializeOwned;
+
+use super::model::{ApiFailure, ErrorBody, ErrorResponse, SuccessResponse};
+
+pub(super) fn success_response<T: Serialize>(
+    status: StatusCode,
+    data: T,
+    revision: String,
+) -> hyper::Response<Full<Bytes>> {
+    let payload = SuccessResponse {
+        ok: true,
+        data,
+        revision,
+    };
+    let body = serde_json::to_vec(&payload).unwrap_or_else(|_| b"{\"ok\":false}".to_vec());
+    hyper::Response::builder()
+        .status(status)
+        .header("content-type", "application/json; charset=utf-8")
+        .body(Full::new(Bytes::from(body)))
+        .unwrap()
+}
+
+pub(super) fn error_response(
+    request_id: u64,
+    failure: ApiFailure,
+) -> hyper::Response<Full<Bytes>> {
+    let payload = ErrorResponse {
+        ok: false,
+        error: ErrorBody {
+            code: failure.code,
+            message: failure.message,
+        },
+        request_id,
+    };
+    let body = serde_json::to_vec(&payload).unwrap_or_else(|_| {
+        format!(
+            "{{\"ok\":false,\"error\":{{\"code\":\"internal_error\",\"message\":\"serialization failed\"}},\"request_id\":{}}}",
+            request_id
+        )
+        .into_bytes()
+    });
+    hyper::Response::builder()
+        .status(failure.status)
+        .header("content-type", "application/json; charset=utf-8")
+        .body(Full::new(Bytes::from(body)))
+        .unwrap()
+}
+
+pub(super) async fn read_json<T: DeserializeOwned>(
+    body: Incoming,
+    limit: usize,
+) -> Result<T, ApiFailure> {
+    let bytes = read_body_with_limit(body, limit).await?;
+    serde_json::from_slice(&bytes).map_err(|_| ApiFailure::bad_request("Invalid JSON body"))
+}
+
+pub(super) async fn read_optional_json<T: DeserializeOwned>(
+    body: Incoming,
+    limit: usize,
+) -> Result<Option<T>, ApiFailure> {
+    let bytes = read_body_with_limit(body, limit).await?;
+    if bytes.is_empty() {
+        return Ok(None);
+    }
+    serde_json::from_slice(&bytes)
+        .map(Some)
+        .map_err(|_| ApiFailure::bad_request("Invalid JSON body"))
+}
+
+async fn read_body_with_limit(body: Incoming, limit: usize) -> Result<Vec<u8>, ApiFailure> {
+    let mut collected = Vec::new();
+    let mut body = body;
+    while let Some(frame_result) = body.frame().await {
+        let frame = frame_result.map_err(|_| ApiFailure::bad_request("Invalid request body"))?;
+        if let Some(chunk) = frame.data_ref() {
+            if collected.len().saturating_add(chunk.len()) > limit {
+                return Err(ApiFailure::new(
+                    StatusCode::PAYLOAD_TOO_LARGE,
+                    "payload_too_large",
+                    format!("Body exceeds {} bytes", limit),
+                ));
+            }
+            collected.extend_from_slice(chunk);
+        }
+    }
+    Ok(collected)
+}

src/api/mod.rs

@@ -1,51 +1,88 @@
 use std::convert::Infallible;
-use std::net::SocketAddr;
+use std::net::{IpAddr, SocketAddr};
 use std::path::PathBuf;
 use std::sync::Arc;
-use std::sync::atomic::{AtomicU64, Ordering};
+use std::sync::atomic::{AtomicBool, AtomicU64, Ordering};
 
-use http_body_util::{BodyExt, Full};
+use http_body_util::Full;
 use hyper::body::{Bytes, Incoming};
 use hyper::header::AUTHORIZATION;
 use hyper::server::conn::http1;
 use hyper::service::service_fn;
 use hyper::{Method, Request, Response, StatusCode};
-use serde::Serialize;
-use serde::de::DeserializeOwned;
 use tokio::net::TcpListener;
-use tokio::sync::{Mutex, watch};
+use tokio::sync::{Mutex, RwLock, watch};
 use tracing::{debug, info, warn};
 
 use crate::config::ProxyConfig;
 use crate::ip_tracker::UserIpTracker;
+use crate::startup::StartupTracker;
 use crate::stats::Stats;
 use crate::transport::middle_proxy::MePool;
+use crate::transport::UpstreamManager;
 
 mod config_store;
+mod events;
+mod http_utils;
 mod model;
+mod runtime_edge;
+mod runtime_init;
+mod runtime_min;
 mod runtime_stats;
+mod runtime_watch;
+mod runtime_zero;
 mod users;
 
 use config_store::{current_revision, parse_if_match};
+use http_utils::{error_response, read_json, read_optional_json, success_response};
+use events::ApiEventStore;
 use model::{
-    ApiFailure, CreateUserRequest, ErrorBody, ErrorResponse, HealthData, PatchUserRequest,
-    RotateSecretRequest, SuccessResponse, SummaryData,
+    ApiFailure, CreateUserRequest, HealthData, PatchUserRequest, RotateSecretRequest, SummaryData,
+};
+use runtime_edge::{
+    EdgeConnectionsCacheEntry, build_runtime_connections_summary_data,
+    build_runtime_events_recent_data,
+};
+use runtime_init::build_runtime_initialization_data;
+use runtime_min::{
+    build_runtime_me_pool_state_data, build_runtime_me_quality_data, build_runtime_nat_stun_data,
+    build_runtime_upstream_quality_data, build_security_whitelist_data,
 };
 use runtime_stats::{
     MinimalCacheEntry, build_dcs_data, build_me_writers_data, build_minimal_all_data,
-    build_zero_all_data,
+    build_upstreams_data, build_zero_all_data,
 };
+use runtime_zero::{
+    build_limits_effective_data, build_runtime_gates_data, build_security_posture_data,
+    build_system_info_data,
+};
+use runtime_watch::spawn_runtime_watchers;
 use users::{create_user, delete_user, patch_user, rotate_secret, users_from_config};
 
+pub(super) struct ApiRuntimeState {
+    pub(super) process_started_at_epoch_secs: u64,
+    pub(super) config_reload_count: AtomicU64,
+    pub(super) last_config_reload_epoch_secs: AtomicU64,
+    pub(super) admission_open: AtomicBool,
+}
+
 #[derive(Clone)]
 pub(super) struct ApiShared {
     pub(super) stats: Arc<Stats>,
     pub(super) ip_tracker: Arc<UserIpTracker>,
-    pub(super) me_pool: Option<Arc<MePool>>,
+    pub(super) me_pool: Arc<RwLock<Option<Arc<MePool>>>>,
+    pub(super) upstream_manager: Arc<UpstreamManager>,
     pub(super) config_path: PathBuf,
+    pub(super) startup_detected_ip_v4: Option<IpAddr>,
+    pub(super) startup_detected_ip_v6: Option<IpAddr>,
     pub(super) mutation_lock: Arc<Mutex<()>>,
     pub(super) minimal_cache: Arc<Mutex<Option<MinimalCacheEntry>>>,
+    pub(super) runtime_edge_connections_cache: Arc<Mutex<Option<EdgeConnectionsCacheEntry>>>,
+    pub(super) runtime_edge_recompute_lock: Arc<Mutex<()>>,
+    pub(super) runtime_events: Arc<ApiEventStore>,
     pub(super) request_id: Arc<AtomicU64>,
+    pub(super) runtime_state: Arc<ApiRuntimeState>,
+    pub(super) startup_tracker: Arc<StartupTracker>,
 }
 
 impl ApiShared {
@@ -58,9 +95,15 @@ pub async fn serve(
     listen: SocketAddr,
     stats: Arc<Stats>,
     ip_tracker: Arc<UserIpTracker>,
-    me_pool: Option<Arc<MePool>>,
+    me_pool: Arc<RwLock<Option<Arc<MePool>>>>,
+    upstream_manager: Arc<UpstreamManager>,
     config_rx: watch::Receiver<Arc<ProxyConfig>>,
+    admission_rx: watch::Receiver<bool>,
     config_path: PathBuf,
+    startup_detected_ip_v4: Option<IpAddr>,
+    startup_detected_ip_v6: Option<IpAddr>,
+    process_started_at_epoch_secs: u64,
+    startup_tracker: Arc<StartupTracker>,
 ) {
     let listener = match TcpListener::bind(listen).await {
         Ok(listener) => listener,
@@ -76,16 +119,40 @@ pub async fn serve(
 
     info!("API endpoint: http://{}/v1/*", listen);
 
+    let runtime_state = Arc::new(ApiRuntimeState {
+        process_started_at_epoch_secs,
+        config_reload_count: AtomicU64::new(0),
+        last_config_reload_epoch_secs: AtomicU64::new(0),
+        admission_open: AtomicBool::new(*admission_rx.borrow()),
+    });
+
     let shared = Arc::new(ApiShared {
         stats,
         ip_tracker,
         me_pool,
+        upstream_manager,
         config_path,
+        startup_detected_ip_v4,
+        startup_detected_ip_v6,
         mutation_lock: Arc::new(Mutex::new(())),
         minimal_cache: Arc::new(Mutex::new(None)),
+        runtime_edge_connections_cache: Arc::new(Mutex::new(None)),
+        runtime_edge_recompute_lock: Arc::new(Mutex::new(())),
+        runtime_events: Arc::new(ApiEventStore::new(
+            config_rx.borrow().server.api.runtime_edge_events_capacity,
+        )),
         request_id: Arc::new(AtomicU64::new(1)),
+        runtime_state: runtime_state.clone(),
+        startup_tracker,
     });
 
+    spawn_runtime_watchers(
+        config_rx.clone(),
+        admission_rx.clone(),
+        runtime_state.clone(),
+        shared.runtime_events.clone(),
+    );
+
     loop {
         let (stream, peer) = match listener.accept().await {
             Ok(v) => v,
@@ -167,6 +234,7 @@ async fn handle(
 
     let method = req.method().clone();
     let path = req.uri().path().to_string();
+    let query = req.uri().query().map(str::to_string);
     let body_limit = api_cfg.request_body_limit_bytes;
 
     let result: Result<Response<Full<Bytes>>, ApiFailure> = async {
@@ -179,6 +247,36 @@ async fn handle(
                 };
                 Ok(success_response(StatusCode::OK, data, revision))
             }
+            ("GET", "/v1/system/info") => {
+                let revision = current_revision(&shared.config_path).await?;
+                let data = build_system_info_data(shared.as_ref(), cfg.as_ref(), &revision);
+                Ok(success_response(StatusCode::OK, data, revision))
+            }
+            ("GET", "/v1/runtime/gates") => {
+                let revision = current_revision(&shared.config_path).await?;
+                let data = build_runtime_gates_data(shared.as_ref(), cfg.as_ref()).await;
+                Ok(success_response(StatusCode::OK, data, revision))
+            }
+            ("GET", "/v1/runtime/initialization") => {
+                let revision = current_revision(&shared.config_path).await?;
+                let data = build_runtime_initialization_data(shared.as_ref()).await;
+                Ok(success_response(StatusCode::OK, data, revision))
+            }
+            ("GET", "/v1/limits/effective") => {
+                let revision = current_revision(&shared.config_path).await?;
+                let data = build_limits_effective_data(cfg.as_ref());
+                Ok(success_response(StatusCode::OK, data, revision))
+            }
+            ("GET", "/v1/security/posture") => {
+                let revision = current_revision(&shared.config_path).await?;
+                let data = build_security_posture_data(cfg.as_ref());
+                Ok(success_response(StatusCode::OK, data, revision))
+            }
+            ("GET", "/v1/security/whitelist") => {
+                let revision = current_revision(&shared.config_path).await?;
+                let data = build_security_whitelist_data(cfg.as_ref());
+                Ok(success_response(StatusCode::OK, data, revision))
+            }
             ("GET", "/v1/stats/summary") => {
                 let revision = current_revision(&shared.config_path).await?;
                 let data = SummaryData {
@@ -195,6 +293,11 @@ async fn handle(
                 let data = build_zero_all_data(&shared.stats, cfg.access.users.len());
                 Ok(success_response(StatusCode::OK, data, revision))
             }
+            ("GET", "/v1/stats/upstreams") => {
+                let revision = current_revision(&shared.config_path).await?;
+                let data = build_upstreams_data(shared.as_ref(), api_cfg);
+                Ok(success_response(StatusCode::OK, data, revision))
+            }
             ("GET", "/v1/stats/minimal/all") => {
                 let revision = current_revision(&shared.config_path).await?;
                 let data = build_minimal_all_data(shared.as_ref(), api_cfg).await;
@@ -210,9 +313,50 @@ async fn handle(
                 let data = build_dcs_data(shared.as_ref(), api_cfg).await;
                 Ok(success_response(StatusCode::OK, data, revision))
             }
+            ("GET", "/v1/runtime/me_pool_state") => {
+                let revision = current_revision(&shared.config_path).await?;
+                let data = build_runtime_me_pool_state_data(shared.as_ref()).await;
+                Ok(success_response(StatusCode::OK, data, revision))
+            }
+            ("GET", "/v1/runtime/me_quality") => {
+                let revision = current_revision(&shared.config_path).await?;
+                let data = build_runtime_me_quality_data(shared.as_ref()).await;
+                Ok(success_response(StatusCode::OK, data, revision))
+            }
+            ("GET", "/v1/runtime/upstream_quality") => {
+                let revision = current_revision(&shared.config_path).await?;
+                let data = build_runtime_upstream_quality_data(shared.as_ref()).await;
+                Ok(success_response(StatusCode::OK, data, revision))
+            }
+            ("GET", "/v1/runtime/nat_stun") => {
+                let revision = current_revision(&shared.config_path).await?;
+                let data = build_runtime_nat_stun_data(shared.as_ref()).await;
+                Ok(success_response(StatusCode::OK, data, revision))
+            }
+            ("GET", "/v1/runtime/connections/summary") => {
+                let revision = current_revision(&shared.config_path).await?;
+                let data = build_runtime_connections_summary_data(shared.as_ref(), cfg.as_ref()).await;
+                Ok(success_response(StatusCode::OK, data, revision))
+            }
+            ("GET", "/v1/runtime/events/recent") => {
+                let revision = current_revision(&shared.config_path).await?;
+                let data = build_runtime_events_recent_data(
+                    shared.as_ref(),
+                    cfg.as_ref(),
+                    query.as_deref(),
+                );
+                Ok(success_response(StatusCode::OK, data, revision))
+            }
             ("GET", "/v1/stats/users") | ("GET", "/v1/users") => {
                 let revision = current_revision(&shared.config_path).await?;
-                let users = users_from_config(&cfg, &shared.stats, &shared.ip_tracker).await;
+                let users = users_from_config(
+                    &cfg,
+                    &shared.stats,
+                    &shared.ip_tracker,
+                    shared.startup_detected_ip_v4,
+                    shared.startup_detected_ip_v6,
+                )
+                .await;
                 Ok(success_response(StatusCode::OK, users, revision))
             }
             ("POST", "/v1/users") => {
@@ -228,7 +372,17 @@ async fn handle(
                 }
                 let expected_revision = parse_if_match(req.headers());
                 let body = read_json::<CreateUserRequest>(req.into_body(), body_limit).await?;
-                let (data, revision) = create_user(body, expected_revision, &shared).await?;
+                let result = create_user(body, expected_revision, &shared).await;
+                let (data, revision) = match result {
+                    Ok(ok) => ok,
+                    Err(error) => {
+                        shared.runtime_events.record("api.user.create.failed", error.code);
+                        return Err(error);
+                    }
+                };
+                shared
+                    .runtime_events
+                    .record("api.user.create.ok", format!("username={}", data.user.username));
                 Ok(success_response(StatusCode::CREATED, data, revision))
             }
             _ => {
@@ -238,7 +392,14 @@ async fn handle(
                 {
                     if method == Method::GET {
                         let revision = current_revision(&shared.config_path).await?;
-                        let users = users_from_config(&cfg, &shared.stats, &shared.ip_tracker).await;
+                        let users = users_from_config(
+                            &cfg,
+                            &shared.stats,
+                            &shared.ip_tracker,
+                            shared.startup_detected_ip_v4,
+                            shared.startup_detected_ip_v6,
+                        )
+                        .await;
                         if let Some(user_info) = users.into_iter().find(|entry| entry.username == user)
                         {
                             return Ok(success_response(StatusCode::OK, user_info, revision));
@@ -261,8 +422,20 @@ async fn handle(
                         }
                         let expected_revision = parse_if_match(req.headers());
                         let body = read_json::<PatchUserRequest>(req.into_body(), body_limit).await?;
-                        let (data, revision) =
-                            patch_user(user, body, expected_revision, &shared).await?;
+                        let result = patch_user(user, body, expected_revision, &shared).await;
+                        let (data, revision) = match result {
+                            Ok(ok) => ok,
+                            Err(error) => {
+                                shared.runtime_events.record(
+                                    "api.user.patch.failed",
+                                    format!("username={} code={}", user, error.code),
+                                );
+                                return Err(error);
+                            }
+                        };
+                        shared
+                            .runtime_events
+                            .record("api.user.patch.ok", format!("username={}", data.username));
                         return Ok(success_response(StatusCode::OK, data, revision));
                     }
                     if method == Method::DELETE {
@@ -277,8 +450,21 @@ async fn handle(
                             ));
                         }
                         let expected_revision = parse_if_match(req.headers());
-                        let (deleted_user, revision) =
-                            delete_user(user, expected_revision, &shared).await?;
+                        let result = delete_user(user, expected_revision, &shared).await;
+                        let (deleted_user, revision) = match result {
+                            Ok(ok) => ok,
+                            Err(error) => {
+                                shared.runtime_events.record(
+                                    "api.user.delete.failed",
+                                    format!("username={} code={}", user, error.code),
+                                );
+                                return Err(error);
+                            }
+                        };
+                        shared.runtime_events.record(
+                            "api.user.delete.ok",
+                            format!("username={}", deleted_user),
+                        );
                         return Ok(success_response(StatusCode::OK, deleted_user, revision));
                     }
                     if method == Method::POST
@@ -300,9 +486,27 @@ async fn handle(
                         let body =
                             read_optional_json::<RotateSecretRequest>(req.into_body(), body_limit)
                                 .await?;
-                        let (data, revision) =
-                            rotate_secret(base_user, body.unwrap_or_default(), expected_revision, &shared)
-                                .await?;
+                        let result = rotate_secret(
+                            base_user,
+                            body.unwrap_or_default(),
+                            expected_revision,
+                            &shared,
+                        )
+                        .await;
+                        let (data, revision) = match result {
+                            Ok(ok) => ok,
+                            Err(error) => {
+                                shared.runtime_events.record(
+                                    "api.user.rotate_secret.failed",
+                                    format!("username={} code={}", base_user, error.code),
+                                );
+                                return Err(error);
+                            }
+                        };
+                        shared.runtime_events.record(
+                            "api.user.rotate_secret.ok",
+                            format!("username={}", base_user),
+                        );
                         return Ok(success_response(StatusCode::OK, data, revision));
                     }
                     if method == Method::POST {
@@ -334,81 +538,3 @@ async fn handle(
         Err(error) => Ok(error_response(request_id, error)),
     }
 }
-
-fn success_response<T: Serialize>(
-    status: StatusCode,
-    data: T,
-    revision: String,
-) -> Response<Full<Bytes>> {
-    let payload = SuccessResponse {
-        ok: true,
-        data,
-        revision,
-    };
-    let body = serde_json::to_vec(&payload).unwrap_or_else(|_| b"{\"ok\":false}".to_vec());
-    Response::builder()
-        .status(status)
-        .header("content-type", "application/json; charset=utf-8")
-        .body(Full::new(Bytes::from(body)))
-        .unwrap()
-}
-
-fn error_response(request_id: u64, failure: ApiFailure) -> Response<Full<Bytes>> {
-    let payload = ErrorResponse {
-        ok: false,
-        error: ErrorBody {
-            code: failure.code,
-            message: failure.message,
-        },
-        request_id,
-    };
-    let body = serde_json::to_vec(&payload).unwrap_or_else(|_| {
-        format!(
-            "{{\"ok\":false,\"error\":{{\"code\":\"internal_error\",\"message\":\"serialization failed\"}},\"request_id\":{}}}",
-            request_id
-        )
-        .into_bytes()
-    });
-    Response::builder()
-        .status(failure.status)
-        .header("content-type", "application/json; charset=utf-8")
-        .body(Full::new(Bytes::from(body)))
-        .unwrap()
-}
-
-async fn read_json<T: DeserializeOwned>(body: Incoming, limit: usize) -> Result<T, ApiFailure> {
-    let bytes = read_body_with_limit(body, limit).await?;
-    serde_json::from_slice(&bytes).map_err(|_| ApiFailure::bad_request("Invalid JSON body"))
-}
-
-async fn read_optional_json<T: DeserializeOwned>(
-    body: Incoming,
-    limit: usize,
-) -> Result<Option<T>, ApiFailure> {
-    let bytes = read_body_with_limit(body, limit).await?;
-    if bytes.is_empty() {
-        return Ok(None);
-    }
-    serde_json::from_slice(&bytes)
-        .map(Some)
-        .map_err(|_| ApiFailure::bad_request("Invalid JSON body"))
-}
-
-async fn read_body_with_limit(body: Incoming, limit: usize) -> Result<Vec<u8>, ApiFailure> {
-    let mut collected = Vec::new();
-    let mut body = body;
-    while let Some(frame_result) = body.frame().await {
-        let frame = frame_result.map_err(|_| ApiFailure::bad_request("Invalid request body"))?;
-        if let Some(chunk) = frame.data_ref() {
-            if collected.len().saturating_add(chunk.len()) > limit {
-                return Err(ApiFailure::new(
-                    StatusCode::PAYLOAD_TOO_LARGE,
-                    "payload_too_large",
-                    format!("Body exceeds {} bytes", limit),
-                ));
-            }
-            collected.extend_from_slice(chunk);
-        }
-    }
-    Ok(collected)
-}

src/api/model.rs

@@ -1,3 +1,5 @@
+use std::net::IpAddr;
+
 use chrono::{DateTime, Utc};
 use hyper::StatusCode;
 use rand::Rng;
@@ -103,6 +105,50 @@ pub(super) struct ZeroUpstreamData {
     pub(super) connect_duration_fail_bucket_gt_1000ms: u64,
 }
 
+#[derive(Serialize, Clone)]
+pub(super) struct UpstreamDcStatus {
+    pub(super) dc: i16,
+    pub(super) latency_ema_ms: Option<f64>,
+    pub(super) ip_preference: &'static str,
+}
+
+#[derive(Serialize, Clone)]
+pub(super) struct UpstreamStatus {
+    pub(super) upstream_id: usize,
+    pub(super) route_kind: &'static str,
+    pub(super) address: String,
+    pub(super) weight: u16,
+    pub(super) scopes: String,
+    pub(super) healthy: bool,
+    pub(super) fails: u32,
+    pub(super) last_check_age_secs: u64,
+    pub(super) effective_latency_ms: Option<f64>,
+    pub(super) dc: Vec<UpstreamDcStatus>,
+}
+
+#[derive(Serialize, Clone)]
+pub(super) struct UpstreamSummaryData {
+    pub(super) configured_total: usize,
+    pub(super) healthy_total: usize,
+    pub(super) unhealthy_total: usize,
+    pub(super) direct_total: usize,
+    pub(super) socks4_total: usize,
+    pub(super) socks5_total: usize,
+}
+
+#[derive(Serialize, Clone)]
+pub(super) struct UpstreamsData {
+    pub(super) enabled: bool,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub(super) reason: Option<&'static str>,
+    pub(super) generated_at_epoch_secs: u64,
+    pub(super) zero: ZeroUpstreamData,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub(super) summary: Option<UpstreamSummaryData>,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub(super) upstreams: Option<Vec<UpstreamStatus>>,
+}
+
 #[derive(Serialize, Clone)]
 pub(super) struct ZeroMiddleProxyData {
     pub(super) keepalive_sent_total: u64,
@@ -223,6 +269,10 @@ pub(super) struct DcStatus {
     pub(super) available_endpoints: usize,
     pub(super) available_pct: f64,
     pub(super) required_writers: usize,
+    pub(super) floor_min: usize,
+    pub(super) floor_target: usize,
+    pub(super) floor_max: usize,
+    pub(super) floor_capped: bool,
     pub(super) alive_writers: usize,
     pub(super) coverage_pct: f64,
     pub(super) rtt_ms: Option<f64>,
@@ -262,7 +312,27 @@ pub(super) struct MinimalMeRuntimeData {
     pub(super) floor_mode: &'static str,
     pub(super) adaptive_floor_idle_secs: u64,
     pub(super) adaptive_floor_min_writers_single_endpoint: u8,
+    pub(super) adaptive_floor_min_writers_multi_endpoint: u8,
     pub(super) adaptive_floor_recover_grace_secs: u64,
+    pub(super) adaptive_floor_writers_per_core_total: u16,
+    pub(super) adaptive_floor_cpu_cores_override: u16,
+    pub(super) adaptive_floor_max_extra_writers_single_per_core: u16,
+    pub(super) adaptive_floor_max_extra_writers_multi_per_core: u16,
+    pub(super) adaptive_floor_max_active_writers_per_core: u16,
+    pub(super) adaptive_floor_max_warm_writers_per_core: u16,
+    pub(super) adaptive_floor_max_active_writers_global: u32,
+    pub(super) adaptive_floor_max_warm_writers_global: u32,
+    pub(super) adaptive_floor_cpu_cores_detected: u32,
+    pub(super) adaptive_floor_cpu_cores_effective: u32,
+    pub(super) adaptive_floor_global_cap_raw: u64,
+    pub(super) adaptive_floor_global_cap_effective: u64,
+    pub(super) adaptive_floor_target_writers_total: u64,
+    pub(super) adaptive_floor_active_cap_configured: u64,
+    pub(super) adaptive_floor_active_cap_effective: u64,
+    pub(super) adaptive_floor_warm_cap_configured: u64,
+    pub(super) adaptive_floor_warm_cap_effective: u64,
+    pub(super) adaptive_floor_active_writers_current: u64,
+    pub(super) adaptive_floor_warm_writers_current: u64,
     pub(super) me_keepalive_enabled: bool,
     pub(super) me_keepalive_interval_secs: u64,
     pub(super) me_keepalive_jitter_secs: u64,
@@ -325,6 +395,9 @@ pub(super) struct UserInfo {
     pub(super) max_unique_ips: Option<usize>,
     pub(super) current_connections: u64,
     pub(super) active_unique_ips: usize,
+    pub(super) active_unique_ips_list: Vec<IpAddr>,
+    pub(super) recent_unique_ips: usize,
+    pub(super) recent_unique_ips_list: Vec<IpAddr>,
     pub(super) total_octets: u64,
     pub(super) links: UserLinks,
 }

src/api/runtime_edge.rs

@@ -0,0 +1,294 @@
+use std::cmp::Reverse;
+use std::time::{Duration, Instant, SystemTime, UNIX_EPOCH};
+
+use serde::Serialize;
+
+use crate::config::ProxyConfig;
+
+use super::ApiShared;
+use super::events::ApiEventRecord;
+
+const FEATURE_DISABLED_REASON: &str = "feature_disabled";
+const SOURCE_UNAVAILABLE_REASON: &str = "source_unavailable";
+const EVENTS_DEFAULT_LIMIT: usize = 50;
+const EVENTS_MAX_LIMIT: usize = 1000;
+
+#[derive(Clone, Serialize)]
+pub(super) struct RuntimeEdgeConnectionUserData {
+    pub(super) username: String,
+    pub(super) current_connections: u64,
+    pub(super) total_octets: u64,
+}
+
+#[derive(Clone, Serialize)]
+pub(super) struct RuntimeEdgeConnectionTotalsData {
+    pub(super) current_connections: u64,
+    pub(super) current_connections_me: u64,
+    pub(super) current_connections_direct: u64,
+    pub(super) active_users: usize,
+}
+
+#[derive(Clone, Serialize)]
+pub(super) struct RuntimeEdgeConnectionTopData {
+    pub(super) limit: usize,
+    pub(super) by_connections: Vec<RuntimeEdgeConnectionUserData>,
+    pub(super) by_throughput: Vec<RuntimeEdgeConnectionUserData>,
+}
+
+#[derive(Clone, Serialize)]
+pub(super) struct RuntimeEdgeConnectionCacheData {
+    pub(super) ttl_ms: u64,
+    pub(super) served_from_cache: bool,
+    pub(super) stale_cache_used: bool,
+}
+
+#[derive(Clone, Serialize)]
+pub(super) struct RuntimeEdgeConnectionTelemetryData {
+    pub(super) user_enabled: bool,
+    pub(super) throughput_is_cumulative: bool,
+}
+
+#[derive(Clone, Serialize)]
+pub(super) struct RuntimeEdgeConnectionsSummaryPayload {
+    pub(super) cache: RuntimeEdgeConnectionCacheData,
+    pub(super) totals: RuntimeEdgeConnectionTotalsData,
+    pub(super) top: RuntimeEdgeConnectionTopData,
+    pub(super) telemetry: RuntimeEdgeConnectionTelemetryData,
+}
+
+#[derive(Serialize)]
+pub(super) struct RuntimeEdgeConnectionsSummaryData {
+    pub(super) enabled: bool,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub(super) reason: Option<&'static str>,
+    pub(super) generated_at_epoch_secs: u64,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub(super) data: Option<RuntimeEdgeConnectionsSummaryPayload>,
+}
+
+#[derive(Clone)]
+pub(crate) struct EdgeConnectionsCacheEntry {
+    pub(super) expires_at: Instant,
+    pub(super) payload: RuntimeEdgeConnectionsSummaryPayload,
+    pub(super) generated_at_epoch_secs: u64,
+}
+
+#[derive(Serialize)]
+pub(super) struct RuntimeEdgeEventsPayload {
+    pub(super) capacity: usize,
+    pub(super) dropped_total: u64,
+    pub(super) events: Vec<ApiEventRecord>,
+}
+
+#[derive(Serialize)]
+pub(super) struct RuntimeEdgeEventsData {
+    pub(super) enabled: bool,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub(super) reason: Option<&'static str>,
+    pub(super) generated_at_epoch_secs: u64,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub(super) data: Option<RuntimeEdgeEventsPayload>,
+}
+
+pub(super) async fn build_runtime_connections_summary_data(
+    shared: &ApiShared,
+    cfg: &ProxyConfig,
+) -> RuntimeEdgeConnectionsSummaryData {
+    let now_epoch_secs = now_epoch_secs();
+    let api_cfg = &cfg.server.api;
+    if !api_cfg.runtime_edge_enabled {
+        return RuntimeEdgeConnectionsSummaryData {
+            enabled: false,
+            reason: Some(FEATURE_DISABLED_REASON),
+            generated_at_epoch_secs: now_epoch_secs,
+            data: None,
+        };
+    }
+
+    let (generated_at_epoch_secs, payload) = match get_connections_payload_cached(
+        shared,
+        api_cfg.runtime_edge_cache_ttl_ms,
+        api_cfg.runtime_edge_top_n,
+    )
+    .await
+    {
+        Some(v) => v,
+        None => {
+            return RuntimeEdgeConnectionsSummaryData {
+                enabled: true,
+                reason: Some(SOURCE_UNAVAILABLE_REASON),
+                generated_at_epoch_secs: now_epoch_secs,
+                data: None,
+            };
+        }
+    };
+
+    RuntimeEdgeConnectionsSummaryData {
+        enabled: true,
+        reason: None,
+        generated_at_epoch_secs,
+        data: Some(payload),
+    }
+}
+
+pub(super) fn build_runtime_events_recent_data(
+    shared: &ApiShared,
+    cfg: &ProxyConfig,
+    query: Option<&str>,
+) -> RuntimeEdgeEventsData {
+    let now_epoch_secs = now_epoch_secs();
+    let api_cfg = &cfg.server.api;
+    if !api_cfg.runtime_edge_enabled {
+        return RuntimeEdgeEventsData {
+            enabled: false,
+            reason: Some(FEATURE_DISABLED_REASON),
+            generated_at_epoch_secs: now_epoch_secs,
+            data: None,
+        };
+    }
+
+    let limit = parse_recent_events_limit(query, EVENTS_DEFAULT_LIMIT, EVENTS_MAX_LIMIT);
+    let snapshot = shared.runtime_events.snapshot(limit);
+
+    RuntimeEdgeEventsData {
+        enabled: true,
+        reason: None,
+        generated_at_epoch_secs: now_epoch_secs,
+        data: Some(RuntimeEdgeEventsPayload {
+            capacity: snapshot.capacity,
+            dropped_total: snapshot.dropped_total,
+            events: snapshot.events,
+        }),
+    }
+}
+
+async fn get_connections_payload_cached(
+    shared: &ApiShared,
+    cache_ttl_ms: u64,
+    top_n: usize,
+) -> Option<(u64, RuntimeEdgeConnectionsSummaryPayload)> {
+    if cache_ttl_ms > 0 {
+        let now = Instant::now();
+        let cached = shared.runtime_edge_connections_cache.lock().await.clone();
+        if let Some(entry) = cached
+            && now < entry.expires_at
+        {
+            let mut payload = entry.payload;
+            payload.cache.served_from_cache = true;
+            payload.cache.stale_cache_used = false;
+            return Some((entry.generated_at_epoch_secs, payload));
+        }
+    }
+
+    let Ok(_guard) = shared.runtime_edge_recompute_lock.try_lock() else {
+        let cached = shared.runtime_edge_connections_cache.lock().await.clone();
+        if let Some(entry) = cached {
+            let mut payload = entry.payload;
+            payload.cache.served_from_cache = true;
+            payload.cache.stale_cache_used = true;
+            return Some((entry.generated_at_epoch_secs, payload));
+        }
+        return None;
+    };
+
+    let generated_at_epoch_secs = now_epoch_secs();
+    let payload = recompute_connections_payload(shared, cache_ttl_ms, top_n).await;
+
+    if cache_ttl_ms > 0 {
+        let entry = EdgeConnectionsCacheEntry {
+            expires_at: Instant::now() + Duration::from_millis(cache_ttl_ms),
+            payload: payload.clone(),
+            generated_at_epoch_secs,
+        };
+        *shared.runtime_edge_connections_cache.lock().await = Some(entry);
+    }
+
+    Some((generated_at_epoch_secs, payload))
+}
+
+async fn recompute_connections_payload(
+    shared: &ApiShared,
+    cache_ttl_ms: u64,
+    top_n: usize,
+) -> RuntimeEdgeConnectionsSummaryPayload {
+    let mut rows = Vec::<RuntimeEdgeConnectionUserData>::new();
+    let mut active_users = 0usize;
+    for entry in shared.stats.iter_user_stats() {
+        let user_stats = entry.value();
+        let current_connections = user_stats
+            .curr_connects
+            .load(std::sync::atomic::Ordering::Relaxed);
+        let total_octets = user_stats
+            .octets_from_client
+            .load(std::sync::atomic::Ordering::Relaxed)
+            .saturating_add(
+                user_stats
+                    .octets_to_client
+                    .load(std::sync::atomic::Ordering::Relaxed),
+            );
+        if current_connections > 0 {
+            active_users = active_users.saturating_add(1);
+        }
+        rows.push(RuntimeEdgeConnectionUserData {
+            username: entry.key().clone(),
+            current_connections,
+            total_octets,
+        });
+    }
+
+    let limit = top_n.max(1);
+    let mut by_connections = rows.clone();
+    by_connections.sort_by_key(|row| (Reverse(row.current_connections), row.username.clone()));
+    by_connections.truncate(limit);
+
+    let mut by_throughput = rows;
+    by_throughput.sort_by_key(|row| (Reverse(row.total_octets), row.username.clone()));
+    by_throughput.truncate(limit);
+
+    let telemetry = shared.stats.telemetry_policy();
+    RuntimeEdgeConnectionsSummaryPayload {
+        cache: RuntimeEdgeConnectionCacheData {
+            ttl_ms: cache_ttl_ms,
+            served_from_cache: false,
+            stale_cache_used: false,
+        },
+        totals: RuntimeEdgeConnectionTotalsData {
+            current_connections: shared.stats.get_current_connections_total(),
+            current_connections_me: shared.stats.get_current_connections_me(),
+            current_connections_direct: shared.stats.get_current_connections_direct(),
+            active_users,
+        },
+        top: RuntimeEdgeConnectionTopData {
+            limit,
+            by_connections,
+            by_throughput,
+        },
+        telemetry: RuntimeEdgeConnectionTelemetryData {
+            user_enabled: telemetry.user_enabled,
+            throughput_is_cumulative: true,
+        },
+    }
+}
+
+fn parse_recent_events_limit(query: Option<&str>, default_limit: usize, max_limit: usize) -> usize {
+    let Some(query) = query else {
+        return default_limit;
+    };
+    for pair in query.split('&') {
+        let mut split = pair.splitn(2, '=');
+        if split.next() == Some("limit")
+            && let Some(raw) = split.next()
+            && let Ok(parsed) = raw.parse::<usize>()
+        {
+            return parsed.clamp(1, max_limit);
+        }
+    }
+    default_limit
+}
+
+fn now_epoch_secs() -> u64 {
+    SystemTime::now()
+        .duration_since(UNIX_EPOCH)
+        .unwrap_or_default()
+        .as_secs()
+}

src/api/runtime_init.rs

@@ -0,0 +1,186 @@
+use serde::Serialize;
+
+use crate::startup::{
+    COMPONENT_ME_CONNECTIVITY_PING, COMPONENT_ME_POOL_CONSTRUCT, COMPONENT_ME_POOL_INIT_STAGE1,
+    COMPONENT_ME_PROXY_CONFIG_V4, COMPONENT_ME_PROXY_CONFIG_V6, COMPONENT_ME_SECRET_FETCH,
+    StartupComponentStatus, StartupMeStatus, compute_progress_pct,
+};
+
+use super::ApiShared;
+
+#[derive(Serialize)]
+pub(super) struct RuntimeInitializationComponentData {
+    pub(super) id: &'static str,
+    pub(super) title: &'static str,
+    pub(super) status: &'static str,
+    pub(super) started_at_epoch_ms: Option<u64>,
+    pub(super) finished_at_epoch_ms: Option<u64>,
+    pub(super) duration_ms: Option<u64>,
+    pub(super) attempts: u32,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub(super) details: Option<String>,
+}
+
+#[derive(Serialize)]
+pub(super) struct RuntimeInitializationMeData {
+    pub(super) status: &'static str,
+    pub(super) current_stage: String,
+    pub(super) progress_pct: f64,
+    pub(super) init_attempt: u32,
+    pub(super) retry_limit: String,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub(super) last_error: Option<String>,
+}
+
+#[derive(Serialize)]
+pub(super) struct RuntimeInitializationData {
+    pub(super) status: &'static str,
+    pub(super) degraded: bool,
+    pub(super) current_stage: String,
+    pub(super) progress_pct: f64,
+    pub(super) started_at_epoch_secs: u64,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub(super) ready_at_epoch_secs: Option<u64>,
+    pub(super) total_elapsed_ms: u64,
+    pub(super) transport_mode: String,
+    pub(super) me: RuntimeInitializationMeData,
+    pub(super) components: Vec<RuntimeInitializationComponentData>,
+}
+
+#[derive(Clone)]
+pub(super) struct RuntimeStartupSummaryData {
+    pub(super) status: &'static str,
+    pub(super) stage: String,
+    pub(super) progress_pct: f64,
+}
+
+pub(super) async fn build_runtime_startup_summary(shared: &ApiShared) -> RuntimeStartupSummaryData {
+    let snapshot = shared.startup_tracker.snapshot().await;
+    let me_pool_progress = current_me_pool_stage_progress(shared).await;
+    let progress_pct = compute_progress_pct(&snapshot, me_pool_progress);
+    RuntimeStartupSummaryData {
+        status: snapshot.status.as_str(),
+        stage: snapshot.current_stage,
+        progress_pct,
+    }
+}
+
+pub(super) async fn build_runtime_initialization_data(
+    shared: &ApiShared,
+) -> RuntimeInitializationData {
+    let snapshot = shared.startup_tracker.snapshot().await;
+    let me_pool_progress = current_me_pool_stage_progress(shared).await;
+    let progress_pct = compute_progress_pct(&snapshot, me_pool_progress);
+    let me_progress_pct = compute_me_progress_pct(&snapshot, me_pool_progress);
+
+    RuntimeInitializationData {
+        status: snapshot.status.as_str(),
+        degraded: snapshot.degraded,
+        current_stage: snapshot.current_stage,
+        progress_pct,
+        started_at_epoch_secs: snapshot.started_at_epoch_secs,
+        ready_at_epoch_secs: snapshot.ready_at_epoch_secs,
+        total_elapsed_ms: snapshot.total_elapsed_ms,
+        transport_mode: snapshot.transport_mode,
+        me: RuntimeInitializationMeData {
+            status: snapshot.me.status.as_str(),
+            current_stage: snapshot.me.current_stage,
+            progress_pct: me_progress_pct,
+            init_attempt: snapshot.me.init_attempt,
+            retry_limit: snapshot.me.retry_limit,
+            last_error: snapshot.me.last_error,
+        },
+        components: snapshot
+            .components
+            .into_iter()
+            .map(|component| RuntimeInitializationComponentData {
+                id: component.id,
+                title: component.title,
+                status: component.status.as_str(),
+                started_at_epoch_ms: component.started_at_epoch_ms,
+                finished_at_epoch_ms: component.finished_at_epoch_ms,
+                duration_ms: component.duration_ms,
+                attempts: component.attempts,
+                details: component.details,
+            })
+            .collect(),
+    }
+}
+
+fn compute_me_progress_pct(
+    snapshot: &crate::startup::StartupSnapshot,
+    me_pool_progress: Option<f64>,
+) -> f64 {
+    match snapshot.me.status {
+        StartupMeStatus::Pending => 0.0,
+        StartupMeStatus::Ready | StartupMeStatus::Failed | StartupMeStatus::Skipped => 100.0,
+        StartupMeStatus::Initializing => {
+            let mut total_weight = 0.0f64;
+            let mut completed_weight = 0.0f64;
+            for component in &snapshot.components {
+                if !is_me_component(component.id) {
+                    continue;
+                }
+                total_weight += component.weight;
+                let unit_progress = match component.status {
+                    StartupComponentStatus::Pending => 0.0,
+                    StartupComponentStatus::Running => {
+                        if component.id == COMPONENT_ME_POOL_INIT_STAGE1 {
+                            me_pool_progress.unwrap_or(0.0).clamp(0.0, 1.0)
+                        } else {
+                            0.0
+                        }
+                    }
+                    StartupComponentStatus::Ready
+                    | StartupComponentStatus::Failed
+                    | StartupComponentStatus::Skipped => 1.0,
+                };
+                completed_weight += component.weight * unit_progress;
+            }
+            if total_weight <= f64::EPSILON {
+                0.0
+            } else {
+                ((completed_weight / total_weight) * 100.0).clamp(0.0, 100.0)
+            }
+        }
+    }
+}
+
+fn is_me_component(component_id: &str) -> bool {
+    matches!(
+        component_id,
+        COMPONENT_ME_SECRET_FETCH
+            | COMPONENT_ME_PROXY_CONFIG_V4
+            | COMPONENT_ME_PROXY_CONFIG_V6
+            | COMPONENT_ME_POOL_CONSTRUCT
+            | COMPONENT_ME_POOL_INIT_STAGE1
+            | COMPONENT_ME_CONNECTIVITY_PING
+    )
+}
+
+async fn current_me_pool_stage_progress(shared: &ApiShared) -> Option<f64> {
+    let snapshot = shared.startup_tracker.snapshot().await;
+    if snapshot.me.status != StartupMeStatus::Initializing {
+        return None;
+    }
+
+    let pool = shared.me_pool.read().await.clone()?;
+    let status = pool.api_status_snapshot().await;
+    let configured_dc_groups = status.configured_dc_groups;
+    let covered_dc_groups = status
+        .dcs
+        .iter()
+        .filter(|dc| dc.alive_writers > 0)
+        .count();
+
+    let dc_coverage = ratio_01(covered_dc_groups, configured_dc_groups);
+    let writer_coverage = ratio_01(status.alive_writers, status.required_writers);
+    Some((0.7 * dc_coverage + 0.3 * writer_coverage).clamp(0.0, 1.0))
+}
+
+fn ratio_01(part: usize, total: usize) -> f64 {
+    if total == 0 {
+        return 0.0;
+    }
+    ((part as f64) / (total as f64)).clamp(0.0, 1.0)
+}

src/api/runtime_min.rs

@@ -0,0 +1,534 @@
+use std::collections::BTreeSet;
+use std::time::{SystemTime, UNIX_EPOCH};
+
+use serde::Serialize;
+
+use crate::config::ProxyConfig;
+
+use super::ApiShared;
+
+const SOURCE_UNAVAILABLE_REASON: &str = "source_unavailable";
+
+#[derive(Serialize)]
+pub(super) struct SecurityWhitelistData {
+    pub(super) generated_at_epoch_secs: u64,
+    pub(super) enabled: bool,
+    pub(super) entries_total: usize,
+    pub(super) entries: Vec<String>,
+}
+
+#[derive(Serialize)]
+pub(super) struct RuntimeMePoolStateGenerationData {
+    pub(super) active_generation: u64,
+    pub(super) warm_generation: u64,
+    pub(super) pending_hardswap_generation: u64,
+    pub(super) pending_hardswap_age_secs: Option<u64>,
+    pub(super) draining_generations: Vec<u64>,
+}
+
+#[derive(Serialize)]
+pub(super) struct RuntimeMePoolStateHardswapData {
+    pub(super) enabled: bool,
+    pub(super) pending: bool,
+}
+
+#[derive(Serialize)]
+pub(super) struct RuntimeMePoolStateWriterContourData {
+    pub(super) warm: usize,
+    pub(super) active: usize,
+    pub(super) draining: usize,
+}
+
+#[derive(Serialize)]
+pub(super) struct RuntimeMePoolStateWriterHealthData {
+    pub(super) healthy: usize,
+    pub(super) degraded: usize,
+    pub(super) draining: usize,
+}
+
+#[derive(Serialize)]
+pub(super) struct RuntimeMePoolStateWriterData {
+    pub(super) total: usize,
+    pub(super) alive_non_draining: usize,
+    pub(super) draining: usize,
+    pub(super) degraded: usize,
+    pub(super) contour: RuntimeMePoolStateWriterContourData,
+    pub(super) health: RuntimeMePoolStateWriterHealthData,
+}
+
+#[derive(Serialize)]
+pub(super) struct RuntimeMePoolStateRefillDcData {
+    pub(super) dc: i16,
+    pub(super) family: &'static str,
+    pub(super) inflight: usize,
+}
+
+#[derive(Serialize)]
+pub(super) struct RuntimeMePoolStateRefillData {
+    pub(super) inflight_endpoints_total: usize,
+    pub(super) inflight_dc_total: usize,
+    pub(super) by_dc: Vec<RuntimeMePoolStateRefillDcData>,
+}
+
+#[derive(Serialize)]
+pub(super) struct RuntimeMePoolStatePayload {
+    pub(super) generations: RuntimeMePoolStateGenerationData,
+    pub(super) hardswap: RuntimeMePoolStateHardswapData,
+    pub(super) writers: RuntimeMePoolStateWriterData,
+    pub(super) refill: RuntimeMePoolStateRefillData,
+}
+
+#[derive(Serialize)]
+pub(super) struct RuntimeMePoolStateData {
+    pub(super) enabled: bool,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub(super) reason: Option<&'static str>,
+    pub(super) generated_at_epoch_secs: u64,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub(super) data: Option<RuntimeMePoolStatePayload>,
+}
+
+#[derive(Serialize)]
+pub(super) struct RuntimeMeQualityCountersData {
+    pub(super) idle_close_by_peer_total: u64,
+    pub(super) reader_eof_total: u64,
+    pub(super) kdf_drift_total: u64,
+    pub(super) kdf_port_only_drift_total: u64,
+    pub(super) reconnect_attempt_total: u64,
+    pub(super) reconnect_success_total: u64,
+}
+
+#[derive(Serialize)]
+pub(super) struct RuntimeMeQualityRouteDropData {
+    pub(super) no_conn_total: u64,
+    pub(super) channel_closed_total: u64,
+    pub(super) queue_full_total: u64,
+    pub(super) queue_full_base_total: u64,
+    pub(super) queue_full_high_total: u64,
+}
+
+#[derive(Serialize)]
+pub(super) struct RuntimeMeQualityDcRttData {
+    pub(super) dc: i16,
+    pub(super) rtt_ema_ms: Option<f64>,
+    pub(super) alive_writers: usize,
+    pub(super) required_writers: usize,
+    pub(super) coverage_pct: f64,
+}
+
+#[derive(Serialize)]
+pub(super) struct RuntimeMeQualityPayload {
+    pub(super) counters: RuntimeMeQualityCountersData,
+    pub(super) route_drops: RuntimeMeQualityRouteDropData,
+    pub(super) dc_rtt: Vec<RuntimeMeQualityDcRttData>,
+}
+
+#[derive(Serialize)]
+pub(super) struct RuntimeMeQualityData {
+    pub(super) enabled: bool,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub(super) reason: Option<&'static str>,
+    pub(super) generated_at_epoch_secs: u64,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub(super) data: Option<RuntimeMeQualityPayload>,
+}
+
+#[derive(Serialize)]
+pub(super) struct RuntimeUpstreamQualityPolicyData {
+    pub(super) connect_retry_attempts: u32,
+    pub(super) connect_retry_backoff_ms: u64,
+    pub(super) connect_budget_ms: u64,
+    pub(super) unhealthy_fail_threshold: u32,
+    pub(super) connect_failfast_hard_errors: bool,
+}
+
+#[derive(Serialize)]
+pub(super) struct RuntimeUpstreamQualityCountersData {
+    pub(super) connect_attempt_total: u64,
+    pub(super) connect_success_total: u64,
+    pub(super) connect_fail_total: u64,
+    pub(super) connect_failfast_hard_error_total: u64,
+}
+
+#[derive(Serialize)]
+pub(super) struct RuntimeUpstreamQualitySummaryData {
+    pub(super) configured_total: usize,
+    pub(super) healthy_total: usize,
+    pub(super) unhealthy_total: usize,
+    pub(super) direct_total: usize,
+    pub(super) socks4_total: usize,
+    pub(super) socks5_total: usize,
+}
+
+#[derive(Serialize)]
+pub(super) struct RuntimeUpstreamQualityDcData {
+    pub(super) dc: i16,
+    pub(super) latency_ema_ms: Option<f64>,
+    pub(super) ip_preference: &'static str,
+}
+
+#[derive(Serialize)]
+pub(super) struct RuntimeUpstreamQualityUpstreamData {
+    pub(super) upstream_id: usize,
+    pub(super) route_kind: &'static str,
+    pub(super) address: String,
+    pub(super) weight: u16,
+    pub(super) scopes: String,
+    pub(super) healthy: bool,
+    pub(super) fails: u32,
+    pub(super) last_check_age_secs: u64,
+    pub(super) effective_latency_ms: Option<f64>,
+    pub(super) dc: Vec<RuntimeUpstreamQualityDcData>,
+}
+
+#[derive(Serialize)]
+pub(super) struct RuntimeUpstreamQualityData {
+    pub(super) enabled: bool,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub(super) reason: Option<&'static str>,
+    pub(super) generated_at_epoch_secs: u64,
+    pub(super) policy: RuntimeUpstreamQualityPolicyData,
+    pub(super) counters: RuntimeUpstreamQualityCountersData,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub(super) summary: Option<RuntimeUpstreamQualitySummaryData>,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub(super) upstreams: Option<Vec<RuntimeUpstreamQualityUpstreamData>>,
+}
+
+#[derive(Serialize)]
+pub(super) struct RuntimeNatStunReflectionData {
+    pub(super) addr: String,
+    pub(super) age_secs: u64,
+}
+
+#[derive(Serialize)]
+pub(super) struct RuntimeNatStunFlagsData {
+    pub(super) nat_probe_enabled: bool,
+    pub(super) nat_probe_disabled_runtime: bool,
+    pub(super) nat_probe_attempts: u8,
+}
+
+#[derive(Serialize)]
+pub(super) struct RuntimeNatStunServersData {
+    pub(super) configured: Vec<String>,
+    pub(super) live: Vec<String>,
+    pub(super) live_total: usize,
+}
+
+#[derive(Serialize)]
+pub(super) struct RuntimeNatStunReflectionBlockData {
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub(super) v4: Option<RuntimeNatStunReflectionData>,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub(super) v6: Option<RuntimeNatStunReflectionData>,
+}
+
+#[derive(Serialize)]
+pub(super) struct RuntimeNatStunPayload {
+    pub(super) flags: RuntimeNatStunFlagsData,
+    pub(super) servers: RuntimeNatStunServersData,
+    pub(super) reflection: RuntimeNatStunReflectionBlockData,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub(super) stun_backoff_remaining_ms: Option<u64>,
+}
+
+#[derive(Serialize)]
+pub(super) struct RuntimeNatStunData {
+    pub(super) enabled: bool,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub(super) reason: Option<&'static str>,
+    pub(super) generated_at_epoch_secs: u64,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub(super) data: Option<RuntimeNatStunPayload>,
+}
+
+pub(super) fn build_security_whitelist_data(cfg: &ProxyConfig) -> SecurityWhitelistData {
+    let entries = cfg
+        .server
+        .api
+        .whitelist
+        .iter()
+        .map(ToString::to_string)
+        .collect::<Vec<_>>();
+    SecurityWhitelistData {
+        generated_at_epoch_secs: now_epoch_secs(),
+        enabled: !entries.is_empty(),
+        entries_total: entries.len(),
+        entries,
+    }
+}
+
+pub(super) async fn build_runtime_me_pool_state_data(shared: &ApiShared) -> RuntimeMePoolStateData {
+    let now_epoch_secs = now_epoch_secs();
+    let Some(pool) = shared.me_pool.read().await.clone() else {
+        return RuntimeMePoolStateData {
+            enabled: false,
+            reason: Some(SOURCE_UNAVAILABLE_REASON),
+            generated_at_epoch_secs: now_epoch_secs,
+            data: None,
+        };
+    };
+
+    let status = pool.api_status_snapshot().await;
+    let runtime = pool.api_runtime_snapshot().await;
+    let refill = pool.api_refill_snapshot().await;
+
+    let mut draining_generations = BTreeSet::<u64>::new();
+    let mut contour_warm = 0usize;
+    let mut contour_active = 0usize;
+    let mut contour_draining = 0usize;
+    let mut draining = 0usize;
+    let mut degraded = 0usize;
+    let mut healthy = 0usize;
+
+    for writer in &status.writers {
+        if writer.draining {
+            draining_generations.insert(writer.generation);
+            draining += 1;
+        }
+        if writer.degraded && !writer.draining {
+            degraded += 1;
+        }
+        if !writer.degraded && !writer.draining {
+            healthy += 1;
+        }
+        match writer.state {
+            "warm" => contour_warm += 1,
+            "active" => contour_active += 1,
+            _ => contour_draining += 1,
+        }
+    }
+
+    RuntimeMePoolStateData {
+        enabled: true,
+        reason: None,
+        generated_at_epoch_secs: status.generated_at_epoch_secs,
+        data: Some(RuntimeMePoolStatePayload {
+            generations: RuntimeMePoolStateGenerationData {
+                active_generation: runtime.active_generation,
+                warm_generation: runtime.warm_generation,
+                pending_hardswap_generation: runtime.pending_hardswap_generation,
+                pending_hardswap_age_secs: runtime.pending_hardswap_age_secs,
+                draining_generations: draining_generations.into_iter().collect(),
+            },
+            hardswap: RuntimeMePoolStateHardswapData {
+                enabled: runtime.hardswap_enabled,
+                pending: runtime.pending_hardswap_generation != 0,
+            },
+            writers: RuntimeMePoolStateWriterData {
+                total: status.writers.len(),
+                alive_non_draining: status.writers.len().saturating_sub(draining),
+                draining,
+                degraded,
+                contour: RuntimeMePoolStateWriterContourData {
+                    warm: contour_warm,
+                    active: contour_active,
+                    draining: contour_draining,
+                },
+                health: RuntimeMePoolStateWriterHealthData {
+                    healthy,
+                    degraded,
+                    draining,
+                },
+            },
+            refill: RuntimeMePoolStateRefillData {
+                inflight_endpoints_total: refill.inflight_endpoints_total,
+                inflight_dc_total: refill.inflight_dc_total,
+                by_dc: refill
+                    .by_dc
+                    .into_iter()
+                    .map(|entry| RuntimeMePoolStateRefillDcData {
+                        dc: entry.dc,
+                        family: entry.family,
+                        inflight: entry.inflight,
+                    })
+                    .collect(),
+            },
+        }),
+    }
+}
+
+pub(super) async fn build_runtime_me_quality_data(shared: &ApiShared) -> RuntimeMeQualityData {
+    let now_epoch_secs = now_epoch_secs();
+    let Some(pool) = shared.me_pool.read().await.clone() else {
+        return RuntimeMeQualityData {
+            enabled: false,
+            reason: Some(SOURCE_UNAVAILABLE_REASON),
+            generated_at_epoch_secs: now_epoch_secs,
+            data: None,
+        };
+    };
+
+    let status = pool.api_status_snapshot().await;
+    RuntimeMeQualityData {
+        enabled: true,
+        reason: None,
+        generated_at_epoch_secs: status.generated_at_epoch_secs,
+        data: Some(RuntimeMeQualityPayload {
+            counters: RuntimeMeQualityCountersData {
+                idle_close_by_peer_total: shared.stats.get_me_idle_close_by_peer_total(),
+                reader_eof_total: shared.stats.get_me_reader_eof_total(),
+                kdf_drift_total: shared.stats.get_me_kdf_drift_total(),
+                kdf_port_only_drift_total: shared.stats.get_me_kdf_port_only_drift_total(),
+                reconnect_attempt_total: shared.stats.get_me_reconnect_attempts(),
+                reconnect_success_total: shared.stats.get_me_reconnect_success(),
+            },
+            route_drops: RuntimeMeQualityRouteDropData {
+                no_conn_total: shared.stats.get_me_route_drop_no_conn(),
+                channel_closed_total: shared.stats.get_me_route_drop_channel_closed(),
+                queue_full_total: shared.stats.get_me_route_drop_queue_full(),
+                queue_full_base_total: shared.stats.get_me_route_drop_queue_full_base(),
+                queue_full_high_total: shared.stats.get_me_route_drop_queue_full_high(),
+            },
+            dc_rtt: status
+                .dcs
+                .into_iter()
+                .map(|dc| RuntimeMeQualityDcRttData {
+                    dc: dc.dc,
+                    rtt_ema_ms: dc.rtt_ms,
+                    alive_writers: dc.alive_writers,
+                    required_writers: dc.required_writers,
+                    coverage_pct: dc.coverage_pct,
+                })
+                .collect(),
+        }),
+    }
+}
+
+pub(super) async fn build_runtime_upstream_quality_data(
+    shared: &ApiShared,
+) -> RuntimeUpstreamQualityData {
+    let generated_at_epoch_secs = now_epoch_secs();
+    let policy = shared.upstream_manager.api_policy_snapshot();
+    let counters = RuntimeUpstreamQualityCountersData {
+        connect_attempt_total: shared.stats.get_upstream_connect_attempt_total(),
+        connect_success_total: shared.stats.get_upstream_connect_success_total(),
+        connect_fail_total: shared.stats.get_upstream_connect_fail_total(),
+        connect_failfast_hard_error_total: shared.stats.get_upstream_connect_failfast_hard_error_total(),
+    };
+
+    let Some(snapshot) = shared.upstream_manager.try_api_snapshot() else {
+        return RuntimeUpstreamQualityData {
+            enabled: false,
+            reason: Some(SOURCE_UNAVAILABLE_REASON),
+            generated_at_epoch_secs,
+            policy: RuntimeUpstreamQualityPolicyData {
+                connect_retry_attempts: policy.connect_retry_attempts,
+                connect_retry_backoff_ms: policy.connect_retry_backoff_ms,
+                connect_budget_ms: policy.connect_budget_ms,
+                unhealthy_fail_threshold: policy.unhealthy_fail_threshold,
+                connect_failfast_hard_errors: policy.connect_failfast_hard_errors,
+            },
+            counters,
+            summary: None,
+            upstreams: None,
+        };
+    };
+
+    RuntimeUpstreamQualityData {
+        enabled: true,
+        reason: None,
+        generated_at_epoch_secs,
+        policy: RuntimeUpstreamQualityPolicyData {
+            connect_retry_attempts: policy.connect_retry_attempts,
+            connect_retry_backoff_ms: policy.connect_retry_backoff_ms,
+            connect_budget_ms: policy.connect_budget_ms,
+            unhealthy_fail_threshold: policy.unhealthy_fail_threshold,
+            connect_failfast_hard_errors: policy.connect_failfast_hard_errors,
+        },
+        counters,
+        summary: Some(RuntimeUpstreamQualitySummaryData {
+            configured_total: snapshot.summary.configured_total,
+            healthy_total: snapshot.summary.healthy_total,
+            unhealthy_total: snapshot.summary.unhealthy_total,
+            direct_total: snapshot.summary.direct_total,
+            socks4_total: snapshot.summary.socks4_total,
+            socks5_total: snapshot.summary.socks5_total,
+        }),
+        upstreams: Some(
+            snapshot
+                .upstreams
+                .into_iter()
+                .map(|upstream| RuntimeUpstreamQualityUpstreamData {
+                    upstream_id: upstream.upstream_id,
+                    route_kind: match upstream.route_kind {
+                        crate::transport::UpstreamRouteKind::Direct => "direct",
+                        crate::transport::UpstreamRouteKind::Socks4 => "socks4",
+                        crate::transport::UpstreamRouteKind::Socks5 => "socks5",
+                    },
+                    address: upstream.address,
+                    weight: upstream.weight,
+                    scopes: upstream.scopes,
+                    healthy: upstream.healthy,
+                    fails: upstream.fails,
+                    last_check_age_secs: upstream.last_check_age_secs,
+                    effective_latency_ms: upstream.effective_latency_ms,
+                    dc: upstream
+                        .dc
+                        .into_iter()
+                        .map(|dc| RuntimeUpstreamQualityDcData {
+                            dc: dc.dc,
+                            latency_ema_ms: dc.latency_ema_ms,
+                            ip_preference: match dc.ip_preference {
+                                crate::transport::upstream::IpPreference::Unknown => "unknown",
+                                crate::transport::upstream::IpPreference::PreferV6 => "prefer_v6",
+                                crate::transport::upstream::IpPreference::PreferV4 => "prefer_v4",
+                                crate::transport::upstream::IpPreference::BothWork => "both_work",
+                                crate::transport::upstream::IpPreference::Unavailable => "unavailable",
+                            },
+                        })
+                        .collect(),
+                })
+                .collect(),
+        ),
+    }
+}
+
+pub(super) async fn build_runtime_nat_stun_data(shared: &ApiShared) -> RuntimeNatStunData {
+    let now_epoch_secs = now_epoch_secs();
+    let Some(pool) = shared.me_pool.read().await.clone() else {
+        return RuntimeNatStunData {
+            enabled: false,
+            reason: Some(SOURCE_UNAVAILABLE_REASON),
+            generated_at_epoch_secs: now_epoch_secs,
+            data: None,
+        };
+    };
+
+    let snapshot = pool.api_nat_stun_snapshot().await;
+    RuntimeNatStunData {
+        enabled: true,
+        reason: None,
+        generated_at_epoch_secs: now_epoch_secs,
+        data: Some(RuntimeNatStunPayload {
+            flags: RuntimeNatStunFlagsData {
+                nat_probe_enabled: snapshot.nat_probe_enabled,
+                nat_probe_disabled_runtime: snapshot.nat_probe_disabled_runtime,
+                nat_probe_attempts: snapshot.nat_probe_attempts,
+            },
+            servers: RuntimeNatStunServersData {
+                configured: snapshot.configured_servers,
+                live: snapshot.live_servers.clone(),
+                live_total: snapshot.live_servers.len(),
+            },
+            reflection: RuntimeNatStunReflectionBlockData {
+                v4: snapshot.reflection_v4.map(|entry| RuntimeNatStunReflectionData {
+                    addr: entry.addr.to_string(),
+                    age_secs: entry.age_secs,
+                }),
+                v6: snapshot.reflection_v6.map(|entry| RuntimeNatStunReflectionData {
+                    addr: entry.addr.to_string(),
+                    age_secs: entry.age_secs,
+                }),
+            },
+            stun_backoff_remaining_ms: snapshot.stun_backoff_remaining_ms,
+        }),
+    }
+}
+
+fn now_epoch_secs() -> u64 {
+    SystemTime::now()
+        .duration_since(UNIX_EPOCH)
+        .unwrap_or_default()
+        .as_secs()
+}

src/api/runtime_stats.rs

@@ -2,12 +2,15 @@ use std::time::{Duration, Instant, SystemTime, UNIX_EPOCH};
 
 use crate::config::ApiConfig;
 use crate::stats::Stats;
+use crate::transport::upstream::IpPreference;
+use crate::transport::UpstreamRouteKind;
 
 use super::ApiShared;
 use super::model::{
     DcStatus, DcStatusData, MeWriterStatus, MeWritersData, MeWritersSummary, MinimalAllData,
     MinimalAllPayload, MinimalDcPathData, MinimalMeRuntimeData, MinimalQuarantineData,
-    ZeroAllData, ZeroCodeCount, ZeroCoreData, ZeroDesyncData, ZeroMiddleProxyData, ZeroPoolData,
+    UpstreamDcStatus, UpstreamStatus, UpstreamSummaryData, UpstreamsData, ZeroAllData,
+    ZeroCodeCount, ZeroCoreData, ZeroDesyncData, ZeroMiddleProxyData, ZeroPoolData,
     ZeroUpstreamData,
 };
 
@@ -41,32 +44,7 @@ pub(super) fn build_zero_all_data(stats: &Stats, configured_users: usize) -> Zer
             telemetry_user_enabled: telemetry.user_enabled,
             telemetry_me_level: telemetry.me_level.to_string(),
         },
-        upstream: ZeroUpstreamData {
-            connect_attempt_total: stats.get_upstream_connect_attempt_total(),
-            connect_success_total: stats.get_upstream_connect_success_total(),
-            connect_fail_total: stats.get_upstream_connect_fail_total(),
-            connect_failfast_hard_error_total: stats.get_upstream_connect_failfast_hard_error_total(),
-            connect_attempts_bucket_1: stats.get_upstream_connect_attempts_bucket_1(),
-            connect_attempts_bucket_2: stats.get_upstream_connect_attempts_bucket_2(),
-            connect_attempts_bucket_3_4: stats.get_upstream_connect_attempts_bucket_3_4(),
-            connect_attempts_bucket_gt_4: stats.get_upstream_connect_attempts_bucket_gt_4(),
-            connect_duration_success_bucket_le_100ms: stats
-                .get_upstream_connect_duration_success_bucket_le_100ms(),
-            connect_duration_success_bucket_101_500ms: stats
-                .get_upstream_connect_duration_success_bucket_101_500ms(),
-            connect_duration_success_bucket_501_1000ms: stats
-                .get_upstream_connect_duration_success_bucket_501_1000ms(),
-            connect_duration_success_bucket_gt_1000ms: stats
-                .get_upstream_connect_duration_success_bucket_gt_1000ms(),
-            connect_duration_fail_bucket_le_100ms: stats
-                .get_upstream_connect_duration_fail_bucket_le_100ms(),
-            connect_duration_fail_bucket_101_500ms: stats
-                .get_upstream_connect_duration_fail_bucket_101_500ms(),
-            connect_duration_fail_bucket_501_1000ms: stats
-                .get_upstream_connect_duration_fail_bucket_501_1000ms(),
-            connect_duration_fail_bucket_gt_1000ms: stats
-                .get_upstream_connect_duration_fail_bucket_gt_1000ms(),
-        },
+        upstream: build_zero_upstream_data(stats),
         middle_proxy: ZeroMiddleProxyData {
             keepalive_sent_total: stats.get_me_keepalive_sent(),
             keepalive_failed_total: stats.get_me_keepalive_failed(),
@@ -140,6 +118,102 @@ pub(super) fn build_zero_all_data(stats: &Stats, configured_users: usize) -> Zer
     }
 }
 
+fn build_zero_upstream_data(stats: &Stats) -> ZeroUpstreamData {
+    ZeroUpstreamData {
+        connect_attempt_total: stats.get_upstream_connect_attempt_total(),
+        connect_success_total: stats.get_upstream_connect_success_total(),
+        connect_fail_total: stats.get_upstream_connect_fail_total(),
+        connect_failfast_hard_error_total: stats.get_upstream_connect_failfast_hard_error_total(),
+        connect_attempts_bucket_1: stats.get_upstream_connect_attempts_bucket_1(),
+        connect_attempts_bucket_2: stats.get_upstream_connect_attempts_bucket_2(),
+        connect_attempts_bucket_3_4: stats.get_upstream_connect_attempts_bucket_3_4(),
+        connect_attempts_bucket_gt_4: stats.get_upstream_connect_attempts_bucket_gt_4(),
+        connect_duration_success_bucket_le_100ms: stats
+            .get_upstream_connect_duration_success_bucket_le_100ms(),
+        connect_duration_success_bucket_101_500ms: stats
+            .get_upstream_connect_duration_success_bucket_101_500ms(),
+        connect_duration_success_bucket_501_1000ms: stats
+            .get_upstream_connect_duration_success_bucket_501_1000ms(),
+        connect_duration_success_bucket_gt_1000ms: stats
+            .get_upstream_connect_duration_success_bucket_gt_1000ms(),
+        connect_duration_fail_bucket_le_100ms: stats.get_upstream_connect_duration_fail_bucket_le_100ms(),
+        connect_duration_fail_bucket_101_500ms: stats
+            .get_upstream_connect_duration_fail_bucket_101_500ms(),
+        connect_duration_fail_bucket_501_1000ms: stats
+            .get_upstream_connect_duration_fail_bucket_501_1000ms(),
+        connect_duration_fail_bucket_gt_1000ms: stats
+            .get_upstream_connect_duration_fail_bucket_gt_1000ms(),
+    }
+}
+
+pub(super) fn build_upstreams_data(shared: &ApiShared, api_cfg: &ApiConfig) -> UpstreamsData {
+    let generated_at_epoch_secs = now_epoch_secs();
+    let zero = build_zero_upstream_data(&shared.stats);
+    if !api_cfg.minimal_runtime_enabled {
+        return UpstreamsData {
+            enabled: false,
+            reason: Some(FEATURE_DISABLED_REASON),
+            generated_at_epoch_secs,
+            zero,
+            summary: None,
+            upstreams: None,
+        };
+    }
+
+    let Some(snapshot) = shared.upstream_manager.try_api_snapshot() else {
+        return UpstreamsData {
+            enabled: true,
+            reason: Some(SOURCE_UNAVAILABLE_REASON),
+            generated_at_epoch_secs,
+            zero,
+            summary: None,
+            upstreams: None,
+        };
+    };
+
+    let summary = UpstreamSummaryData {
+        configured_total: snapshot.summary.configured_total,
+        healthy_total: snapshot.summary.healthy_total,
+        unhealthy_total: snapshot.summary.unhealthy_total,
+        direct_total: snapshot.summary.direct_total,
+        socks4_total: snapshot.summary.socks4_total,
+        socks5_total: snapshot.summary.socks5_total,
+    };
+    let upstreams = snapshot
+        .upstreams
+        .into_iter()
+        .map(|upstream| UpstreamStatus {
+            upstream_id: upstream.upstream_id,
+            route_kind: map_route_kind(upstream.route_kind),
+            address: upstream.address,
+            weight: upstream.weight,
+            scopes: upstream.scopes,
+            healthy: upstream.healthy,
+            fails: upstream.fails,
+            last_check_age_secs: upstream.last_check_age_secs,
+            effective_latency_ms: upstream.effective_latency_ms,
+            dc: upstream
+                .dc
+                .into_iter()
+                .map(|dc| UpstreamDcStatus {
+                    dc: dc.dc,
+                    latency_ema_ms: dc.latency_ema_ms,
+                    ip_preference: map_ip_preference(dc.ip_preference),
+                })
+                .collect(),
+        })
+        .collect();
+
+    UpstreamsData {
+        enabled: true,
+        reason: None,
+        generated_at_epoch_secs,
+        zero,
+        summary: Some(summary),
+        upstreams: Some(upstreams),
+    }
+}
+
 pub(super) async fn build_minimal_all_data(
     shared: &ApiShared,
     api_cfg: &ApiConfig,
@@ -223,7 +297,7 @@ async fn get_minimal_payload_cached(
         }
     }
 
-    let pool = shared.me_pool.as_ref()?;
+    let pool = shared.me_pool.read().await.clone()?;
     let status = pool.api_status_snapshot().await;
     let runtime = pool.api_runtime_snapshot().await;
     let generated_at_epoch_secs = status.generated_at_epoch_secs;
@@ -275,6 +349,10 @@ async fn get_minimal_payload_cached(
                 available_endpoints: entry.available_endpoints,
                 available_pct: entry.available_pct,
                 required_writers: entry.required_writers,
+                floor_min: entry.floor_min,
+                floor_target: entry.floor_target,
+                floor_max: entry.floor_max,
+                floor_capped: entry.floor_capped,
                 alive_writers: entry.alive_writers,
                 coverage_pct: entry.coverage_pct,
                 rtt_ms: entry.rtt_ms,
@@ -292,7 +370,35 @@ async fn get_minimal_payload_cached(
         adaptive_floor_idle_secs: runtime.adaptive_floor_idle_secs,
         adaptive_floor_min_writers_single_endpoint: runtime
             .adaptive_floor_min_writers_single_endpoint,
+        adaptive_floor_min_writers_multi_endpoint: runtime
+            .adaptive_floor_min_writers_multi_endpoint,
         adaptive_floor_recover_grace_secs: runtime.adaptive_floor_recover_grace_secs,
+        adaptive_floor_writers_per_core_total: runtime
+            .adaptive_floor_writers_per_core_total,
+        adaptive_floor_cpu_cores_override: runtime.adaptive_floor_cpu_cores_override,
+        adaptive_floor_max_extra_writers_single_per_core: runtime
+            .adaptive_floor_max_extra_writers_single_per_core,
+        adaptive_floor_max_extra_writers_multi_per_core: runtime
+            .adaptive_floor_max_extra_writers_multi_per_core,
+        adaptive_floor_max_active_writers_per_core: runtime
+            .adaptive_floor_max_active_writers_per_core,
+        adaptive_floor_max_warm_writers_per_core: runtime
+            .adaptive_floor_max_warm_writers_per_core,
+        adaptive_floor_max_active_writers_global: runtime
+            .adaptive_floor_max_active_writers_global,
+        adaptive_floor_max_warm_writers_global: runtime
+            .adaptive_floor_max_warm_writers_global,
+        adaptive_floor_cpu_cores_detected: runtime.adaptive_floor_cpu_cores_detected,
+        adaptive_floor_cpu_cores_effective: runtime.adaptive_floor_cpu_cores_effective,
+        adaptive_floor_global_cap_raw: runtime.adaptive_floor_global_cap_raw,
+        adaptive_floor_global_cap_effective: runtime.adaptive_floor_global_cap_effective,
+        adaptive_floor_target_writers_total: runtime.adaptive_floor_target_writers_total,
+        adaptive_floor_active_cap_configured: runtime.adaptive_floor_active_cap_configured,
+        adaptive_floor_active_cap_effective: runtime.adaptive_floor_active_cap_effective,
+        adaptive_floor_warm_cap_configured: runtime.adaptive_floor_warm_cap_configured,
+        adaptive_floor_warm_cap_effective: runtime.adaptive_floor_warm_cap_effective,
+        adaptive_floor_active_writers_current: runtime.adaptive_floor_active_writers_current,
+        adaptive_floor_warm_writers_current: runtime.adaptive_floor_warm_writers_current,
         me_keepalive_enabled: runtime.me_keepalive_enabled,
         me_keepalive_interval_secs: runtime.me_keepalive_interval_secs,
         me_keepalive_jitter_secs: runtime.me_keepalive_jitter_secs,
@@ -384,6 +490,24 @@ fn disabled_dcs(now_epoch_secs: u64, reason: &'static str) -> DcStatusData {
     }
 }
 
+fn map_route_kind(value: UpstreamRouteKind) -> &'static str {
+    match value {
+        UpstreamRouteKind::Direct => "direct",
+        UpstreamRouteKind::Socks4 => "socks4",
+        UpstreamRouteKind::Socks5 => "socks5",
+    }
+}
+
+fn map_ip_preference(value: IpPreference) -> &'static str {
+    match value {
+        IpPreference::Unknown => "unknown",
+        IpPreference::PreferV6 => "prefer_v6",
+        IpPreference::PreferV4 => "prefer_v4",
+        IpPreference::BothWork => "both_work",
+        IpPreference::Unavailable => "unavailable",
+    }
+}
+
 fn now_epoch_secs() -> u64 {
     SystemTime::now()
         .duration_since(UNIX_EPOCH)

src/api/runtime_watch.rs

@@ -0,0 +1,66 @@
+use std::sync::Arc;
+use std::sync::atomic::Ordering;
+use std::time::{SystemTime, UNIX_EPOCH};
+
+use tokio::sync::watch;
+
+use crate::config::ProxyConfig;
+
+use super::ApiRuntimeState;
+use super::events::ApiEventStore;
+
+pub(super) fn spawn_runtime_watchers(
+    config_rx: watch::Receiver<Arc<ProxyConfig>>,
+    admission_rx: watch::Receiver<bool>,
+    runtime_state: Arc<ApiRuntimeState>,
+    runtime_events: Arc<ApiEventStore>,
+) {
+    let mut config_rx_reload = config_rx;
+    let runtime_state_reload = runtime_state.clone();
+    let runtime_events_reload = runtime_events.clone();
+    tokio::spawn(async move {
+        loop {
+            if config_rx_reload.changed().await.is_err() {
+                break;
+            }
+            runtime_state_reload
+                .config_reload_count
+                .fetch_add(1, Ordering::Relaxed);
+            runtime_state_reload
+                .last_config_reload_epoch_secs
+                .store(now_epoch_secs(), Ordering::Relaxed);
+            runtime_events_reload.record("config.reload.applied", "config receiver updated");
+        }
+    });
+
+    let mut admission_rx_watch = admission_rx;
+    tokio::spawn(async move {
+        runtime_state
+            .admission_open
+            .store(*admission_rx_watch.borrow(), Ordering::Relaxed);
+        runtime_events.record(
+            "admission.state",
+            format!("accepting_new_connections={}", *admission_rx_watch.borrow()),
+        );
+        loop {
+            if admission_rx_watch.changed().await.is_err() {
+                break;
+            }
+            let admission_open = *admission_rx_watch.borrow();
+            runtime_state
+                .admission_open
+                .store(admission_open, Ordering::Relaxed);
+            runtime_events.record(
+                "admission.state",
+                format!("accepting_new_connections={}", admission_open),
+            );
+        }
+    });
+}
+
+fn now_epoch_secs() -> u64 {
+    SystemTime::now()
+        .duration_since(UNIX_EPOCH)
+        .unwrap_or_default()
+        .as_secs()
+}

src/api/runtime_zero.rs

@@ -0,0 +1,276 @@
+use std::sync::atomic::Ordering;
+
+use serde::Serialize;
+
+use crate::config::{MeFloorMode, ProxyConfig, UserMaxUniqueIpsMode};
+
+use super::ApiShared;
+use super::runtime_init::build_runtime_startup_summary;
+
+#[derive(Serialize)]
+pub(super) struct SystemInfoData {
+    pub(super) version: String,
+    pub(super) target_arch: String,
+    pub(super) target_os: String,
+    pub(super) build_profile: String,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub(super) git_commit: Option<String>,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub(super) build_time_utc: Option<String>,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub(super) rustc_version: Option<String>,
+    pub(super) process_started_at_epoch_secs: u64,
+    pub(super) uptime_seconds: f64,
+    pub(super) config_path: String,
+    pub(super) config_hash: String,
+    pub(super) config_reload_count: u64,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub(super) last_config_reload_epoch_secs: Option<u64>,
+}
+
+#[derive(Serialize)]
+pub(super) struct RuntimeGatesData {
+    pub(super) accepting_new_connections: bool,
+    pub(super) conditional_cast_enabled: bool,
+    pub(super) me_runtime_ready: bool,
+    pub(super) me2dc_fallback_enabled: bool,
+    pub(super) use_middle_proxy: bool,
+    pub(super) startup_status: &'static str,
+    pub(super) startup_stage: String,
+    pub(super) startup_progress_pct: f64,
+}
+
+#[derive(Serialize)]
+pub(super) struct EffectiveTimeoutLimits {
+    pub(super) client_handshake_secs: u64,
+    pub(super) tg_connect_secs: u64,
+    pub(super) client_keepalive_secs: u64,
+    pub(super) client_ack_secs: u64,
+    pub(super) me_one_retry: u8,
+    pub(super) me_one_timeout_ms: u64,
+}
+
+#[derive(Serialize)]
+pub(super) struct EffectiveUpstreamLimits {
+    pub(super) connect_retry_attempts: u32,
+    pub(super) connect_retry_backoff_ms: u64,
+    pub(super) connect_budget_ms: u64,
+    pub(super) unhealthy_fail_threshold: u32,
+    pub(super) connect_failfast_hard_errors: bool,
+}
+
+#[derive(Serialize)]
+pub(super) struct EffectiveMiddleProxyLimits {
+    pub(super) floor_mode: &'static str,
+    pub(super) adaptive_floor_idle_secs: u64,
+    pub(super) adaptive_floor_min_writers_single_endpoint: u8,
+    pub(super) adaptive_floor_min_writers_multi_endpoint: u8,
+    pub(super) adaptive_floor_recover_grace_secs: u64,
+    pub(super) adaptive_floor_writers_per_core_total: u16,
+    pub(super) adaptive_floor_cpu_cores_override: u16,
+    pub(super) adaptive_floor_max_extra_writers_single_per_core: u16,
+    pub(super) adaptive_floor_max_extra_writers_multi_per_core: u16,
+    pub(super) adaptive_floor_max_active_writers_per_core: u16,
+    pub(super) adaptive_floor_max_warm_writers_per_core: u16,
+    pub(super) adaptive_floor_max_active_writers_global: u32,
+    pub(super) adaptive_floor_max_warm_writers_global: u32,
+    pub(super) reconnect_max_concurrent_per_dc: u32,
+    pub(super) reconnect_backoff_base_ms: u64,
+    pub(super) reconnect_backoff_cap_ms: u64,
+    pub(super) reconnect_fast_retry_count: u32,
+    pub(super) me2dc_fallback: bool,
+}
+
+#[derive(Serialize)]
+pub(super) struct EffectiveUserIpPolicyLimits {
+    pub(super) mode: &'static str,
+    pub(super) window_secs: u64,
+}
+
+#[derive(Serialize)]
+pub(super) struct EffectiveLimitsData {
+    pub(super) update_every_secs: u64,
+    pub(super) me_reinit_every_secs: u64,
+    pub(super) me_pool_force_close_secs: u64,
+    pub(super) timeouts: EffectiveTimeoutLimits,
+    pub(super) upstream: EffectiveUpstreamLimits,
+    pub(super) middle_proxy: EffectiveMiddleProxyLimits,
+    pub(super) user_ip_policy: EffectiveUserIpPolicyLimits,
+}
+
+#[derive(Serialize)]
+pub(super) struct SecurityPostureData {
+    pub(super) api_read_only: bool,
+    pub(super) api_whitelist_enabled: bool,
+    pub(super) api_whitelist_entries: usize,
+    pub(super) api_auth_header_enabled: bool,
+    pub(super) proxy_protocol_enabled: bool,
+    pub(super) log_level: String,
+    pub(super) telemetry_core_enabled: bool,
+    pub(super) telemetry_user_enabled: bool,
+    pub(super) telemetry_me_level: String,
+}
+
+pub(super) fn build_system_info_data(
+    shared: &ApiShared,
+    _cfg: &ProxyConfig,
+    revision: &str,
+) -> SystemInfoData {
+    let last_reload_epoch_secs = shared
+        .runtime_state
+        .last_config_reload_epoch_secs
+        .load(Ordering::Relaxed);
+    let last_config_reload_epoch_secs = (last_reload_epoch_secs > 0).then_some(last_reload_epoch_secs);
+
+    let git_commit = option_env!("TELEMT_GIT_COMMIT")
+        .or(option_env!("VERGEN_GIT_SHA"))
+        .or(option_env!("GIT_COMMIT"))
+        .map(ToString::to_string);
+    let build_time_utc = option_env!("BUILD_TIME_UTC")
+        .or(option_env!("VERGEN_BUILD_TIMESTAMP"))
+        .map(ToString::to_string);
+    let rustc_version = option_env!("RUSTC_VERSION")
+        .or(option_env!("VERGEN_RUSTC_SEMVER"))
+        .map(ToString::to_string);
+
+    SystemInfoData {
+        version: env!("CARGO_PKG_VERSION").to_string(),
+        target_arch: std::env::consts::ARCH.to_string(),
+        target_os: std::env::consts::OS.to_string(),
+        build_profile: option_env!("PROFILE").unwrap_or("unknown").to_string(),
+        git_commit,
+        build_time_utc,
+        rustc_version,
+        process_started_at_epoch_secs: shared.runtime_state.process_started_at_epoch_secs,
+        uptime_seconds: shared.stats.uptime_secs(),
+        config_path: shared.config_path.display().to_string(),
+        config_hash: revision.to_string(),
+        config_reload_count: shared.runtime_state.config_reload_count.load(Ordering::Relaxed),
+        last_config_reload_epoch_secs,
+    }
+}
+
+pub(super) async fn build_runtime_gates_data(
+    shared: &ApiShared,
+    cfg: &ProxyConfig,
+) -> RuntimeGatesData {
+    let startup_summary = build_runtime_startup_summary(shared).await;
+    let me_runtime_ready = if !cfg.general.use_middle_proxy {
+        true
+    } else {
+        shared
+            .me_pool
+            .read()
+            .await
+            .as_ref()
+            .map(|pool| pool.is_runtime_ready())
+            .unwrap_or(false)
+    };
+
+    RuntimeGatesData {
+        accepting_new_connections: shared.runtime_state.admission_open.load(Ordering::Relaxed),
+        conditional_cast_enabled: cfg.general.use_middle_proxy,
+        me_runtime_ready,
+        me2dc_fallback_enabled: cfg.general.me2dc_fallback,
+        use_middle_proxy: cfg.general.use_middle_proxy,
+        startup_status: startup_summary.status,
+        startup_stage: startup_summary.stage,
+        startup_progress_pct: startup_summary.progress_pct,
+    }
+}
+
+pub(super) fn build_limits_effective_data(cfg: &ProxyConfig) -> EffectiveLimitsData {
+    EffectiveLimitsData {
+        update_every_secs: cfg.general.effective_update_every_secs(),
+        me_reinit_every_secs: cfg.general.effective_me_reinit_every_secs(),
+        me_pool_force_close_secs: cfg.general.effective_me_pool_force_close_secs(),
+        timeouts: EffectiveTimeoutLimits {
+            client_handshake_secs: cfg.timeouts.client_handshake,
+            tg_connect_secs: cfg.timeouts.tg_connect,
+            client_keepalive_secs: cfg.timeouts.client_keepalive,
+            client_ack_secs: cfg.timeouts.client_ack,
+            me_one_retry: cfg.timeouts.me_one_retry,
+            me_one_timeout_ms: cfg.timeouts.me_one_timeout_ms,
+        },
+        upstream: EffectiveUpstreamLimits {
+            connect_retry_attempts: cfg.general.upstream_connect_retry_attempts,
+            connect_retry_backoff_ms: cfg.general.upstream_connect_retry_backoff_ms,
+            connect_budget_ms: cfg.general.upstream_connect_budget_ms,
+            unhealthy_fail_threshold: cfg.general.upstream_unhealthy_fail_threshold,
+            connect_failfast_hard_errors: cfg.general.upstream_connect_failfast_hard_errors,
+        },
+        middle_proxy: EffectiveMiddleProxyLimits {
+            floor_mode: me_floor_mode_label(cfg.general.me_floor_mode),
+            adaptive_floor_idle_secs: cfg.general.me_adaptive_floor_idle_secs,
+            adaptive_floor_min_writers_single_endpoint: cfg
+                .general
+                .me_adaptive_floor_min_writers_single_endpoint,
+            adaptive_floor_min_writers_multi_endpoint: cfg
+                .general
+                .me_adaptive_floor_min_writers_multi_endpoint,
+            adaptive_floor_recover_grace_secs: cfg.general.me_adaptive_floor_recover_grace_secs,
+            adaptive_floor_writers_per_core_total: cfg
+                .general
+                .me_adaptive_floor_writers_per_core_total,
+            adaptive_floor_cpu_cores_override: cfg
+                .general
+                .me_adaptive_floor_cpu_cores_override,
+            adaptive_floor_max_extra_writers_single_per_core: cfg
+                .general
+                .me_adaptive_floor_max_extra_writers_single_per_core,
+            adaptive_floor_max_extra_writers_multi_per_core: cfg
+                .general
+                .me_adaptive_floor_max_extra_writers_multi_per_core,
+            adaptive_floor_max_active_writers_per_core: cfg
+                .general
+                .me_adaptive_floor_max_active_writers_per_core,
+            adaptive_floor_max_warm_writers_per_core: cfg
+                .general
+                .me_adaptive_floor_max_warm_writers_per_core,
+            adaptive_floor_max_active_writers_global: cfg
+                .general
+                .me_adaptive_floor_max_active_writers_global,
+            adaptive_floor_max_warm_writers_global: cfg
+                .general
+                .me_adaptive_floor_max_warm_writers_global,
+            reconnect_max_concurrent_per_dc: cfg.general.me_reconnect_max_concurrent_per_dc,
+            reconnect_backoff_base_ms: cfg.general.me_reconnect_backoff_base_ms,
+            reconnect_backoff_cap_ms: cfg.general.me_reconnect_backoff_cap_ms,
+            reconnect_fast_retry_count: cfg.general.me_reconnect_fast_retry_count,
+            me2dc_fallback: cfg.general.me2dc_fallback,
+        },
+        user_ip_policy: EffectiveUserIpPolicyLimits {
+            mode: user_max_unique_ips_mode_label(cfg.access.user_max_unique_ips_mode),
+            window_secs: cfg.access.user_max_unique_ips_window_secs,
+        },
+    }
+}
+
+pub(super) fn build_security_posture_data(cfg: &ProxyConfig) -> SecurityPostureData {
+    SecurityPostureData {
+        api_read_only: cfg.server.api.read_only,
+        api_whitelist_enabled: !cfg.server.api.whitelist.is_empty(),
+        api_whitelist_entries: cfg.server.api.whitelist.len(),
+        api_auth_header_enabled: !cfg.server.api.auth_header.is_empty(),
+        proxy_protocol_enabled: cfg.server.proxy_protocol,
+        log_level: cfg.general.log_level.to_string(),
+        telemetry_core_enabled: cfg.general.telemetry.core_enabled,
+        telemetry_user_enabled: cfg.general.telemetry.user_enabled,
+        telemetry_me_level: cfg.general.telemetry.me_level.to_string(),
+    }
+}
+
+fn user_max_unique_ips_mode_label(mode: UserMaxUniqueIpsMode) -> &'static str {
+    match mode {
+        UserMaxUniqueIpsMode::ActiveWindow => "active_window",
+        UserMaxUniqueIpsMode::TimeWindow => "time_window",
+        UserMaxUniqueIpsMode::Combined => "combined",
+    }
+}
+
+fn me_floor_mode_label(mode: MeFloorMode) -> &'static str {
+    match mode {
+        MeFloorMode::Static => "static",
+        MeFloorMode::Adaptive => "adaptive",
+    }
+}

src/api/users.rs

@@ -1,4 +1,3 @@
-use std::collections::HashMap;
 use std::net::IpAddr;
 
 use hyper::StatusCode;
@@ -92,7 +91,14 @@ pub(super) async fn create_user(
         shared.ip_tracker.set_user_limit(&body.username, limit).await;
     }
 
-    let users = users_from_config(&cfg, &shared.stats, &shared.ip_tracker).await;
+    let users = users_from_config(
+        &cfg,
+        &shared.stats,
+        &shared.ip_tracker,
+        shared.startup_detected_ip_v4,
+        shared.startup_detected_ip_v6,
+    )
+    .await;
     let user = users
         .into_iter()
         .find(|entry| entry.username == body.username)
@@ -105,8 +111,16 @@ pub(super) async fn create_user(
             max_unique_ips: updated_limit,
             current_connections: 0,
             active_unique_ips: 0,
+            active_unique_ips_list: Vec::new(),
+            recent_unique_ips: 0,
+            recent_unique_ips_list: Vec::new(),
             total_octets: 0,
-            links: build_user_links(&cfg, &secret),
+            links: build_user_links(
+                &cfg,
+                &secret,
+                shared.startup_detected_ip_v4,
+                shared.startup_detected_ip_v6,
+            ),
         });
 
     Ok((CreateUserResponse { user, secret }, revision))
@@ -171,7 +185,14 @@ pub(super) async fn patch_user(
     if let Some(limit) = updated_limit {
         shared.ip_tracker.set_user_limit(user, limit).await;
     }
-    let users = users_from_config(&cfg, &shared.stats, &shared.ip_tracker).await;
+    let users = users_from_config(
+        &cfg,
+        &shared.stats,
+        &shared.ip_tracker,
+        shared.startup_detected_ip_v4,
+        shared.startup_detected_ip_v6,
+    )
+    .await;
     let user_info = users
         .into_iter()
         .find(|entry| entry.username == user)
@@ -211,7 +232,14 @@ pub(super) async fn rotate_secret(
     let revision = save_config_to_disk(&shared.config_path, &cfg).await?;
     drop(_guard);
 
-    let users = users_from_config(&cfg, &shared.stats, &shared.ip_tracker).await;
+    let users = users_from_config(
+        &cfg,
+        &shared.stats,
+        &shared.ip_tracker,
+        shared.startup_detected_ip_v4,
+        shared.startup_detected_ip_v6,
+    )
+    .await;
     let user_info = users
         .into_iter()
         .find(|entry| entry.username == user)
@@ -261,6 +289,7 @@ pub(super) async fn delete_user(
         .map_err(|e| ApiFailure::bad_request(format!("config validation failed: {}", e)))?;
     let revision = save_config_to_disk(&shared.config_path, &cfg).await?;
     drop(_guard);
+    shared.ip_tracker.remove_user_limit(user).await;
     shared.ip_tracker.clear_user_ips(user).await;
 
     Ok((user.to_string(), revision))
@@ -270,24 +299,36 @@ pub(super) async fn users_from_config(
     cfg: &ProxyConfig,
     stats: &Stats,
     ip_tracker: &UserIpTracker,
+    startup_detected_ip_v4: Option<IpAddr>,
+    startup_detected_ip_v6: Option<IpAddr>,
 ) -> Vec<UserInfo> {
-    let ip_counts = ip_tracker
-        .get_stats()
-        .await
-        .into_iter()
-        .map(|(user, count, _)| (user, count))
-        .collect::<HashMap<_, _>>();
-
     let mut names = cfg.access.users.keys().cloned().collect::<Vec<_>>();
     names.sort();
+    let active_ip_lists = ip_tracker.get_active_ips_for_users(&names).await;
+    let recent_ip_lists = ip_tracker.get_recent_ips_for_users(&names).await;
 
     let mut users = Vec::with_capacity(names.len());
     for username in names {
+        let active_ip_list = active_ip_lists
+            .get(&username)
+            .cloned()
+            .unwrap_or_else(Vec::new);
+        let recent_ip_list = recent_ip_lists
+            .get(&username)
+            .cloned()
+            .unwrap_or_else(Vec::new);
         let links = cfg
             .access
             .users
             .get(&username)
-            .map(|secret| build_user_links(cfg, secret))
+            .map(|secret| {
+                build_user_links(
+                    cfg,
+                    secret,
+                    startup_detected_ip_v4,
+                    startup_detected_ip_v6,
+                )
+            })
             .unwrap_or(UserLinks {
                 classic: Vec::new(),
                 secure: Vec::new(),
@@ -304,7 +345,10 @@ pub(super) async fn users_from_config(
             data_quota_bytes: cfg.access.user_data_quota.get(&username).copied(),
             max_unique_ips: cfg.access.user_max_unique_ips.get(&username).copied(),
             current_connections: stats.get_user_curr_connects(&username),
-            active_unique_ips: ip_counts.get(&username).copied().unwrap_or(0),
+            active_unique_ips: active_ip_list.len(),
+            active_unique_ips_list: active_ip_list,
+            recent_unique_ips: recent_ip_list.len(),
+            recent_unique_ips_list: recent_ip_list,
             total_octets: stats.get_user_total_octets(&username),
             links,
             username,
@@ -313,8 +357,13 @@ pub(super) async fn users_from_config(
     users
 }
 
-fn build_user_links(cfg: &ProxyConfig, secret: &str) -> UserLinks {
-    let hosts = resolve_link_hosts(cfg);
+fn build_user_links(
+    cfg: &ProxyConfig,
+    secret: &str,
+    startup_detected_ip_v4: Option<IpAddr>,
+    startup_detected_ip_v6: Option<IpAddr>,
+) -> UserLinks {
+    let hosts = resolve_link_hosts(cfg, startup_detected_ip_v4, startup_detected_ip_v6);
     let port = cfg.general.links.public_port.unwrap_or(cfg.server.port);
     let tls_domains = resolve_tls_domains(cfg);
 
@@ -353,7 +402,11 @@ fn build_user_links(cfg: &ProxyConfig, secret: &str) -> UserLinks {
     }
 }
 
-fn resolve_link_hosts(cfg: &ProxyConfig) -> Vec<String> {
+fn resolve_link_hosts(
+    cfg: &ProxyConfig,
+    startup_detected_ip_v4: Option<IpAddr>,
+    startup_detected_ip_v6: Option<IpAddr>,
+) -> Vec<String> {
     if let Some(host) = cfg
         .general
         .links
@@ -365,6 +418,17 @@ fn resolve_link_hosts(cfg: &ProxyConfig) -> Vec<String> {
         return vec![host.to_string()];
     }
 
+    let mut startup_hosts = Vec::new();
+    if let Some(ip) = startup_detected_ip_v4 {
+        push_unique_host(&mut startup_hosts, &ip.to_string());
+    }
+    if let Some(ip) = startup_detected_ip_v6 {
+        push_unique_host(&mut startup_hosts, &ip.to_string());
+    }
+    if !startup_hosts.is_empty() {
+        return startup_hosts;
+    }
+
     let mut hosts = Vec::new();
     for listener in &cfg.server.listeners {
         if let Some(host) = listener

src/config/defaults.rs

@@ -11,9 +11,27 @@ const DEFAULT_ME_RECONNECT_FAST_RETRY_COUNT: u32 = 16;
 const DEFAULT_ME_SINGLE_ENDPOINT_SHADOW_WRITERS: u8 = 2;
 const DEFAULT_ME_ADAPTIVE_FLOOR_IDLE_SECS: u64 = 90;
 const DEFAULT_ME_ADAPTIVE_FLOOR_MIN_WRITERS_SINGLE_ENDPOINT: u8 = 1;
+const DEFAULT_ME_ADAPTIVE_FLOOR_MIN_WRITERS_MULTI_ENDPOINT: u8 = 1;
 const DEFAULT_ME_ADAPTIVE_FLOOR_RECOVER_GRACE_SECS: u64 = 180;
+const DEFAULT_ME_ADAPTIVE_FLOOR_WRITERS_PER_CORE_TOTAL: u16 = 48;
+const DEFAULT_ME_ADAPTIVE_FLOOR_CPU_CORES_OVERRIDE: u16 = 0;
+const DEFAULT_ME_ADAPTIVE_FLOOR_MAX_EXTRA_WRITERS_SINGLE_PER_CORE: u16 = 1;
+const DEFAULT_ME_ADAPTIVE_FLOOR_MAX_EXTRA_WRITERS_MULTI_PER_CORE: u16 = 2;
+const DEFAULT_ME_ADAPTIVE_FLOOR_MAX_ACTIVE_WRITERS_PER_CORE: u16 = 64;
+const DEFAULT_ME_ADAPTIVE_FLOOR_MAX_WARM_WRITERS_PER_CORE: u16 = 64;
+const DEFAULT_ME_ADAPTIVE_FLOOR_MAX_ACTIVE_WRITERS_GLOBAL: u32 = 256;
+const DEFAULT_ME_ADAPTIVE_FLOOR_MAX_WARM_WRITERS_GLOBAL: u32 = 256;
+const DEFAULT_ME_WRITER_CMD_CHANNEL_CAPACITY: usize = 512;
+const DEFAULT_ME_ROUTE_CHANNEL_CAPACITY: usize = 512;
+const DEFAULT_ME_C2ME_CHANNEL_CAPACITY: usize = 128;
+const DEFAULT_ME_HEALTH_INTERVAL_MS_UNHEALTHY: u64 = 1000;
+const DEFAULT_ME_HEALTH_INTERVAL_MS_HEALTHY: u64 = 3000;
+const DEFAULT_ME_ADMISSION_POLL_MS: u64 = 1000;
+const DEFAULT_ME_WARN_RATE_LIMIT_MS: u64 = 5000;
+const DEFAULT_USER_MAX_UNIQUE_IPS_WINDOW_SECS: u64 = 30;
 const DEFAULT_UPSTREAM_CONNECT_RETRY_ATTEMPTS: u32 = 2;
 const DEFAULT_UPSTREAM_UNHEALTHY_FAIL_THRESHOLD: u32 = 5;
+const DEFAULT_UPSTREAM_CONNECT_BUDGET_MS: u64 = 3000;
 const DEFAULT_LISTEN_ADDR_IPV6: &str = "::";
 const DEFAULT_ACCESS_USER: &str = "default";
 const DEFAULT_ACCESS_SECRET: &str = "00000000000000000000000000000000";
@@ -112,6 +130,15 @@ pub(crate) fn default_api_minimal_runtime_cache_ttl_ms() -> u64 {
     1000
 }
 
+pub(crate) fn default_api_runtime_edge_enabled() -> bool { false }
+pub(crate) fn default_api_runtime_edge_cache_ttl_ms() -> u64 { 1000 }
+pub(crate) fn default_api_runtime_edge_top_n() -> usize { 10 }
+pub(crate) fn default_api_runtime_edge_events_capacity() -> usize { 256 }
+
+pub(crate) fn default_proxy_protocol_header_timeout_ms() -> u64 {
+    500
+}
+
 pub(crate) fn default_prefer_4() -> u8 {
     4
 }
@@ -128,6 +155,10 @@ pub(crate) fn default_unknown_dc_log_path() -> Option<String> {
     Some("unknown-dc.txt".to_string())
 }
 
+pub(crate) fn default_unknown_dc_file_log_enabled() -> bool {
+    false
+}
+
 pub(crate) fn default_pool_size() -> usize {
     8
 }
@@ -136,6 +167,14 @@ pub(crate) fn default_proxy_secret_path() -> Option<String> {
     Some("proxy-secret".to_string())
 }
 
+pub(crate) fn default_proxy_config_v4_cache_path() -> Option<String> {
+    Some("cache/proxy-config-v4.txt".to_string())
+}
+
+pub(crate) fn default_proxy_config_v6_cache_path() -> Option<String> {
+    Some("cache/proxy-config-v6.txt".to_string())
+}
+
 pub(crate) fn default_middle_proxy_nat_stun() -> Option<String> {
     None
 }
@@ -152,6 +191,14 @@ pub(crate) fn default_middle_proxy_warm_standby() -> usize {
     DEFAULT_MIDDLE_PROXY_WARM_STANDBY
 }
 
+pub(crate) fn default_me_init_retry_attempts() -> u32 {
+    0
+}
+
+pub(crate) fn default_me2dc_fallback() -> bool {
+    true
+}
+
 pub(crate) fn default_keepalive_interval() -> u64 {
     8
 }
@@ -216,10 +263,74 @@ pub(crate) fn default_me_adaptive_floor_min_writers_single_endpoint() -> u8 {
     DEFAULT_ME_ADAPTIVE_FLOOR_MIN_WRITERS_SINGLE_ENDPOINT
 }
 
+pub(crate) fn default_me_adaptive_floor_min_writers_multi_endpoint() -> u8 {
+    DEFAULT_ME_ADAPTIVE_FLOOR_MIN_WRITERS_MULTI_ENDPOINT
+}
+
 pub(crate) fn default_me_adaptive_floor_recover_grace_secs() -> u64 {
     DEFAULT_ME_ADAPTIVE_FLOOR_RECOVER_GRACE_SECS
 }
 
+pub(crate) fn default_me_adaptive_floor_writers_per_core_total() -> u16 {
+    DEFAULT_ME_ADAPTIVE_FLOOR_WRITERS_PER_CORE_TOTAL
+}
+
+pub(crate) fn default_me_adaptive_floor_cpu_cores_override() -> u16 {
+    DEFAULT_ME_ADAPTIVE_FLOOR_CPU_CORES_OVERRIDE
+}
+
+pub(crate) fn default_me_adaptive_floor_max_extra_writers_single_per_core() -> u16 {
+    DEFAULT_ME_ADAPTIVE_FLOOR_MAX_EXTRA_WRITERS_SINGLE_PER_CORE
+}
+
+pub(crate) fn default_me_adaptive_floor_max_extra_writers_multi_per_core() -> u16 {
+    DEFAULT_ME_ADAPTIVE_FLOOR_MAX_EXTRA_WRITERS_MULTI_PER_CORE
+}
+
+pub(crate) fn default_me_adaptive_floor_max_active_writers_per_core() -> u16 {
+    DEFAULT_ME_ADAPTIVE_FLOOR_MAX_ACTIVE_WRITERS_PER_CORE
+}
+
+pub(crate) fn default_me_adaptive_floor_max_warm_writers_per_core() -> u16 {
+    DEFAULT_ME_ADAPTIVE_FLOOR_MAX_WARM_WRITERS_PER_CORE
+}
+
+pub(crate) fn default_me_adaptive_floor_max_active_writers_global() -> u32 {
+    DEFAULT_ME_ADAPTIVE_FLOOR_MAX_ACTIVE_WRITERS_GLOBAL
+}
+
+pub(crate) fn default_me_adaptive_floor_max_warm_writers_global() -> u32 {
+    DEFAULT_ME_ADAPTIVE_FLOOR_MAX_WARM_WRITERS_GLOBAL
+}
+
+pub(crate) fn default_me_writer_cmd_channel_capacity() -> usize {
+    DEFAULT_ME_WRITER_CMD_CHANNEL_CAPACITY
+}
+
+pub(crate) fn default_me_route_channel_capacity() -> usize {
+    DEFAULT_ME_ROUTE_CHANNEL_CAPACITY
+}
+
+pub(crate) fn default_me_c2me_channel_capacity() -> usize {
+    DEFAULT_ME_C2ME_CHANNEL_CAPACITY
+}
+
+pub(crate) fn default_me_health_interval_ms_unhealthy() -> u64 {
+    DEFAULT_ME_HEALTH_INTERVAL_MS_UNHEALTHY
+}
+
+pub(crate) fn default_me_health_interval_ms_healthy() -> u64 {
+    DEFAULT_ME_HEALTH_INTERVAL_MS_HEALTHY
+}
+
+pub(crate) fn default_me_admission_poll_ms() -> u64 {
+    DEFAULT_ME_ADMISSION_POLL_MS
+}
+
+pub(crate) fn default_me_warn_rate_limit_ms() -> u64 {
+    DEFAULT_ME_WARN_RATE_LIMIT_MS
+}
+
 pub(crate) fn default_upstream_connect_retry_attempts() -> u32 {
     DEFAULT_UPSTREAM_CONNECT_RETRY_ATTEMPTS
 }
@@ -232,6 +343,10 @@ pub(crate) fn default_upstream_unhealthy_fail_threshold() -> u32 {
     DEFAULT_UPSTREAM_UNHEALTHY_FAIL_THRESHOLD
 }
 
+pub(crate) fn default_upstream_connect_budget_ms() -> u64 {
+    DEFAULT_UPSTREAM_CONNECT_BUDGET_MS
+}
+
 pub(crate) fn default_upstream_connect_failfast_hard_errors() -> bool {
     false
 }
@@ -264,6 +379,18 @@ pub(crate) fn default_me_route_backpressure_high_watermark_pct() -> u8 {
     80
 }
 
+pub(crate) fn default_me_route_no_writer_wait_ms() -> u64 {
+    250
+}
+
+pub(crate) fn default_me_route_inline_recovery_attempts() -> u32 {
+    3
+}
+
+pub(crate) fn default_me_route_inline_recovery_wait_ms() -> u64 {
+    3000
+}
+
 pub(crate) fn default_beobachten_minutes() -> u64 {
     10
 }
@@ -464,6 +591,10 @@ pub(crate) fn default_access_users() -> HashMap<String, String> {
     )])
 }
 
+pub(crate) fn default_user_max_unique_ips_window_secs() -> u64 {
+    DEFAULT_USER_MAX_UNIQUE_IPS_WINDOW_SECS
+}
+
 // Custom deserializer helpers
 
 #[derive(Deserialize)]

src/config/hot_reload.rs

@@ -9,20 +9,17 @@
 //! | `general` | `log_level`                    | Filter updated via `log_level_tx`              |
 //! | `access`  | `user_ad_tags`                 | Passed on next connection                      |
 //! | `general` | `ad_tag`                       | Passed on next connection (fallback per-user)  |
-//! | `general` | `middle_proxy_pool_size`       | Passed on next connection                      |
-//! | `general` | `me_keepalive_*`               | Passed on next connection                      |
 //! | `general` | `desync_all_full`              | Applied immediately                            |
 //! | `general` | `update_every`                 | Applied to ME updater immediately              |
-//! | `general` | `hardswap`                     | Applied on next ME map update                  |
-//! | `general` | `me_pool_drain_ttl_secs`       | Applied on next ME map update                  |
-//! | `general` | `me_pool_min_fresh_ratio`      | Applied on next ME map update                  |
-//! | `general` | `me_reinit_drain_timeout_secs` | Applied on next ME map update                  |
+//! | `general` | `me_reinit_*`                  | Applied to ME reinit scheduler immediately     |
+//! | `general` | `hardswap` / `me_*_reinit`     | Applied on next ME map update                  |
 //! | `general` | `telemetry` / `me_*_policy`    | Applied immediately                            |
 //! | `network` | `dns_overrides`                | Applied immediately                            |
 //! | `access`  | All user/quota fields          | Effective immediately                          |
 //!
 //! Fields that require re-binding sockets (`server.port`, `censorship.*`,
 //! `network.*`, `use_middle_proxy`) are **not** applied; a warning is emitted.
+//! Non-hot changes are never mixed into the runtime config snapshot.
 
 use std::net::IpAddr;
 use std::path::PathBuf;
@@ -32,7 +29,7 @@ use notify::{EventKind, RecursiveMode, Watcher, recommended_watcher};
 use tokio::sync::{mpsc, watch};
 use tracing::{error, info, warn};
 
-use crate::config::{LogLevel, MeFloorMode, MeSocksKdfPolicy, MeTelemetryLevel};
+use crate::config::{LogLevel, MeBindStaleMode, MeFloorMode, MeSocksKdfPolicy, MeTelemetryLevel};
 use super::load::ProxyConfig;
 
 // ── Hot fields ────────────────────────────────────────────────────────────────
@@ -43,17 +40,37 @@ pub struct HotFields {
     pub log_level:               LogLevel,
     pub ad_tag:                  Option<String>,
     pub dns_overrides:           Vec<String>,
-    pub middle_proxy_pool_size:  usize,
     pub desync_all_full:         bool,
     pub update_every_secs:       u64,
+    pub me_reinit_every_secs:    u64,
+    pub me_reinit_singleflight:  bool,
+    pub me_reinit_coalesce_window_ms: u64,
     pub hardswap:                bool,
     pub me_pool_drain_ttl_secs:  u64,
     pub me_pool_min_fresh_ratio: f32,
     pub me_reinit_drain_timeout_secs: u64,
-    pub me_keepalive_enabled:    bool,
-    pub me_keepalive_interval_secs: u64,
-    pub me_keepalive_jitter_secs:   u64,
-    pub me_keepalive_payload_random: bool,
+    pub me_hardswap_warmup_delay_min_ms: u64,
+    pub me_hardswap_warmup_delay_max_ms: u64,
+    pub me_hardswap_warmup_extra_passes: u8,
+    pub me_hardswap_warmup_pass_backoff_base_ms: u64,
+    pub me_bind_stale_mode: MeBindStaleMode,
+    pub me_bind_stale_ttl_secs: u64,
+    pub me_secret_atomic_snapshot: bool,
+    pub me_deterministic_writer_sort: bool,
+    pub me_single_endpoint_shadow_writers: u8,
+    pub me_single_endpoint_outage_mode_enabled: bool,
+    pub me_single_endpoint_outage_disable_quarantine: bool,
+    pub me_single_endpoint_outage_backoff_min_ms: u64,
+    pub me_single_endpoint_outage_backoff_max_ms: u64,
+    pub me_single_endpoint_shadow_rotate_every_secs: u64,
+    pub me_config_stable_snapshots: u8,
+    pub me_config_apply_cooldown_secs: u64,
+    pub me_snapshot_require_http_2xx: bool,
+    pub me_snapshot_reject_empty_map: bool,
+    pub me_snapshot_min_proxy_for_lines: u32,
+    pub proxy_secret_stable_snapshots: u8,
+    pub proxy_secret_rotate_runtime: bool,
+    pub proxy_secret_len_max: usize,
     pub telemetry_core_enabled: bool,
     pub telemetry_user_enabled: bool,
     pub telemetry_me_level: MeTelemetryLevel,
@@ -61,11 +78,31 @@ pub struct HotFields {
     pub me_floor_mode: MeFloorMode,
     pub me_adaptive_floor_idle_secs: u64,
     pub me_adaptive_floor_min_writers_single_endpoint: u8,
+    pub me_adaptive_floor_min_writers_multi_endpoint: u8,
     pub me_adaptive_floor_recover_grace_secs: u64,
+    pub me_adaptive_floor_writers_per_core_total: u16,
+    pub me_adaptive_floor_cpu_cores_override: u16,
+    pub me_adaptive_floor_max_extra_writers_single_per_core: u16,
+    pub me_adaptive_floor_max_extra_writers_multi_per_core: u16,
+    pub me_adaptive_floor_max_active_writers_per_core: u16,
+    pub me_adaptive_floor_max_warm_writers_per_core: u16,
+    pub me_adaptive_floor_max_active_writers_global: u32,
+    pub me_adaptive_floor_max_warm_writers_global: u32,
     pub me_route_backpressure_base_timeout_ms: u64,
     pub me_route_backpressure_high_timeout_ms: u64,
     pub me_route_backpressure_high_watermark_pct: u8,
-    pub access:                  crate::config::AccessConfig,
+    pub me_health_interval_ms_unhealthy: u64,
+    pub me_health_interval_ms_healthy: u64,
+    pub me_admission_poll_ms: u64,
+    pub me_warn_rate_limit_ms: u64,
+    pub users:                   std::collections::HashMap<String, String>,
+    pub user_ad_tags:            std::collections::HashMap<String, String>,
+    pub user_max_tcp_conns:      std::collections::HashMap<String, usize>,
+    pub user_expirations:        std::collections::HashMap<String, chrono::DateTime<chrono::Utc>>,
+    pub user_data_quota:         std::collections::HashMap<String, u64>,
+    pub user_max_unique_ips:     std::collections::HashMap<String, usize>,
+    pub user_max_unique_ips_mode: crate::config::UserMaxUniqueIpsMode,
+    pub user_max_unique_ips_window_secs: u64,
 }
 
 impl HotFields {
@@ -74,17 +111,49 @@ impl HotFields {
             log_level:               cfg.general.log_level.clone(),
             ad_tag:                  cfg.general.ad_tag.clone(),
             dns_overrides:           cfg.network.dns_overrides.clone(),
-            middle_proxy_pool_size:  cfg.general.middle_proxy_pool_size,
             desync_all_full:         cfg.general.desync_all_full,
             update_every_secs:       cfg.general.effective_update_every_secs(),
+            me_reinit_every_secs:    cfg.general.me_reinit_every_secs,
+            me_reinit_singleflight:  cfg.general.me_reinit_singleflight,
+            me_reinit_coalesce_window_ms: cfg.general.me_reinit_coalesce_window_ms,
             hardswap:                cfg.general.hardswap,
             me_pool_drain_ttl_secs:  cfg.general.me_pool_drain_ttl_secs,
             me_pool_min_fresh_ratio: cfg.general.me_pool_min_fresh_ratio,
             me_reinit_drain_timeout_secs: cfg.general.me_reinit_drain_timeout_secs,
-            me_keepalive_enabled:    cfg.general.me_keepalive_enabled,
-            me_keepalive_interval_secs: cfg.general.me_keepalive_interval_secs,
-            me_keepalive_jitter_secs:   cfg.general.me_keepalive_jitter_secs,
-            me_keepalive_payload_random: cfg.general.me_keepalive_payload_random,
+            me_hardswap_warmup_delay_min_ms: cfg.general.me_hardswap_warmup_delay_min_ms,
+            me_hardswap_warmup_delay_max_ms: cfg.general.me_hardswap_warmup_delay_max_ms,
+            me_hardswap_warmup_extra_passes: cfg.general.me_hardswap_warmup_extra_passes,
+            me_hardswap_warmup_pass_backoff_base_ms: cfg
+                .general
+                .me_hardswap_warmup_pass_backoff_base_ms,
+            me_bind_stale_mode: cfg.general.me_bind_stale_mode,
+            me_bind_stale_ttl_secs: cfg.general.me_bind_stale_ttl_secs,
+            me_secret_atomic_snapshot: cfg.general.me_secret_atomic_snapshot,
+            me_deterministic_writer_sort: cfg.general.me_deterministic_writer_sort,
+            me_single_endpoint_shadow_writers: cfg.general.me_single_endpoint_shadow_writers,
+            me_single_endpoint_outage_mode_enabled: cfg
+                .general
+                .me_single_endpoint_outage_mode_enabled,
+            me_single_endpoint_outage_disable_quarantine: cfg
+                .general
+                .me_single_endpoint_outage_disable_quarantine,
+            me_single_endpoint_outage_backoff_min_ms: cfg
+                .general
+                .me_single_endpoint_outage_backoff_min_ms,
+            me_single_endpoint_outage_backoff_max_ms: cfg
+                .general
+                .me_single_endpoint_outage_backoff_max_ms,
+            me_single_endpoint_shadow_rotate_every_secs: cfg
+                .general
+                .me_single_endpoint_shadow_rotate_every_secs,
+            me_config_stable_snapshots: cfg.general.me_config_stable_snapshots,
+            me_config_apply_cooldown_secs: cfg.general.me_config_apply_cooldown_secs,
+            me_snapshot_require_http_2xx: cfg.general.me_snapshot_require_http_2xx,
+            me_snapshot_reject_empty_map: cfg.general.me_snapshot_reject_empty_map,
+            me_snapshot_min_proxy_for_lines: cfg.general.me_snapshot_min_proxy_for_lines,
+            proxy_secret_stable_snapshots: cfg.general.proxy_secret_stable_snapshots,
+            proxy_secret_rotate_runtime: cfg.general.proxy_secret_rotate_runtime,
+            proxy_secret_len_max: cfg.general.proxy_secret_len_max,
             telemetry_core_enabled: cfg.general.telemetry.core_enabled,
             telemetry_user_enabled: cfg.general.telemetry.user_enabled,
             telemetry_me_level: cfg.general.telemetry.me_level,
@@ -94,22 +163,208 @@ impl HotFields {
             me_adaptive_floor_min_writers_single_endpoint: cfg
                 .general
                 .me_adaptive_floor_min_writers_single_endpoint,
+            me_adaptive_floor_min_writers_multi_endpoint: cfg
+                .general
+                .me_adaptive_floor_min_writers_multi_endpoint,
             me_adaptive_floor_recover_grace_secs: cfg
                 .general
                 .me_adaptive_floor_recover_grace_secs,
+            me_adaptive_floor_writers_per_core_total: cfg
+                .general
+                .me_adaptive_floor_writers_per_core_total,
+            me_adaptive_floor_cpu_cores_override: cfg
+                .general
+                .me_adaptive_floor_cpu_cores_override,
+            me_adaptive_floor_max_extra_writers_single_per_core: cfg
+                .general
+                .me_adaptive_floor_max_extra_writers_single_per_core,
+            me_adaptive_floor_max_extra_writers_multi_per_core: cfg
+                .general
+                .me_adaptive_floor_max_extra_writers_multi_per_core,
+            me_adaptive_floor_max_active_writers_per_core: cfg
+                .general
+                .me_adaptive_floor_max_active_writers_per_core,
+            me_adaptive_floor_max_warm_writers_per_core: cfg
+                .general
+                .me_adaptive_floor_max_warm_writers_per_core,
+            me_adaptive_floor_max_active_writers_global: cfg
+                .general
+                .me_adaptive_floor_max_active_writers_global,
+            me_adaptive_floor_max_warm_writers_global: cfg
+                .general
+                .me_adaptive_floor_max_warm_writers_global,
             me_route_backpressure_base_timeout_ms: cfg.general.me_route_backpressure_base_timeout_ms,
             me_route_backpressure_high_timeout_ms: cfg.general.me_route_backpressure_high_timeout_ms,
             me_route_backpressure_high_watermark_pct: cfg.general.me_route_backpressure_high_watermark_pct,
-            access:                  cfg.access.clone(),
+            me_health_interval_ms_unhealthy: cfg.general.me_health_interval_ms_unhealthy,
+            me_health_interval_ms_healthy: cfg.general.me_health_interval_ms_healthy,
+            me_admission_poll_ms: cfg.general.me_admission_poll_ms,
+            me_warn_rate_limit_ms: cfg.general.me_warn_rate_limit_ms,
+            users:                   cfg.access.users.clone(),
+            user_ad_tags:            cfg.access.user_ad_tags.clone(),
+            user_max_tcp_conns:      cfg.access.user_max_tcp_conns.clone(),
+            user_expirations:        cfg.access.user_expirations.clone(),
+            user_data_quota:         cfg.access.user_data_quota.clone(),
+            user_max_unique_ips:     cfg.access.user_max_unique_ips.clone(),
+            user_max_unique_ips_mode: cfg.access.user_max_unique_ips_mode,
+            user_max_unique_ips_window_secs: cfg.access.user_max_unique_ips_window_secs,
         }
     }
 }
 
 // ── Helpers ───────────────────────────────────────────────────────────────────
 
+fn canonicalize_json(value: &mut serde_json::Value) {
+    match value {
+        serde_json::Value::Object(map) => {
+            let mut pairs: Vec<(String, serde_json::Value)> =
+                std::mem::take(map).into_iter().collect();
+            pairs.sort_by(|a, b| a.0.cmp(&b.0));
+            for (_, item) in pairs.iter_mut() {
+                canonicalize_json(item);
+            }
+            for (key, item) in pairs {
+                map.insert(key, item);
+            }
+        }
+        serde_json::Value::Array(items) => {
+            for item in items {
+                canonicalize_json(item);
+            }
+        }
+        _ => {}
+    }
+}
+
+fn config_equal(lhs: &ProxyConfig, rhs: &ProxyConfig) -> bool {
+    let mut left = match serde_json::to_value(lhs) {
+        Ok(value) => value,
+        Err(_) => return false,
+    };
+    let mut right = match serde_json::to_value(rhs) {
+        Ok(value) => value,
+        Err(_) => return false,
+    };
+    canonicalize_json(&mut left);
+    canonicalize_json(&mut right);
+    left == right
+}
+
+fn listeners_equal(
+    lhs: &[crate::config::ListenerConfig],
+    rhs: &[crate::config::ListenerConfig],
+) -> bool {
+    if lhs.len() != rhs.len() {
+        return false;
+    }
+    lhs.iter().zip(rhs.iter()).all(|(a, b)| {
+        a.ip == b.ip
+            && a.announce == b.announce
+            && a.announce_ip == b.announce_ip
+            && a.proxy_protocol == b.proxy_protocol
+            && a.reuse_allow == b.reuse_allow
+    })
+}
+
+fn overlay_hot_fields(old: &ProxyConfig, new: &ProxyConfig) -> ProxyConfig {
+    let mut cfg = old.clone();
+
+    cfg.general.log_level = new.general.log_level.clone();
+    cfg.general.ad_tag = new.general.ad_tag.clone();
+    cfg.network.dns_overrides = new.network.dns_overrides.clone();
+    cfg.general.desync_all_full = new.general.desync_all_full;
+    cfg.general.update_every = new.general.update_every;
+    cfg.general.proxy_secret_auto_reload_secs = new.general.proxy_secret_auto_reload_secs;
+    cfg.general.proxy_config_auto_reload_secs = new.general.proxy_config_auto_reload_secs;
+    cfg.general.me_reinit_every_secs = new.general.me_reinit_every_secs;
+    cfg.general.me_reinit_singleflight = new.general.me_reinit_singleflight;
+    cfg.general.me_reinit_coalesce_window_ms = new.general.me_reinit_coalesce_window_ms;
+    cfg.general.hardswap = new.general.hardswap;
+    cfg.general.me_pool_drain_ttl_secs = new.general.me_pool_drain_ttl_secs;
+    cfg.general.me_pool_min_fresh_ratio = new.general.me_pool_min_fresh_ratio;
+    cfg.general.me_reinit_drain_timeout_secs = new.general.me_reinit_drain_timeout_secs;
+    cfg.general.me_hardswap_warmup_delay_min_ms = new.general.me_hardswap_warmup_delay_min_ms;
+    cfg.general.me_hardswap_warmup_delay_max_ms = new.general.me_hardswap_warmup_delay_max_ms;
+    cfg.general.me_hardswap_warmup_extra_passes = new.general.me_hardswap_warmup_extra_passes;
+    cfg.general.me_hardswap_warmup_pass_backoff_base_ms =
+        new.general.me_hardswap_warmup_pass_backoff_base_ms;
+    cfg.general.me_bind_stale_mode = new.general.me_bind_stale_mode;
+    cfg.general.me_bind_stale_ttl_secs = new.general.me_bind_stale_ttl_secs;
+    cfg.general.me_secret_atomic_snapshot = new.general.me_secret_atomic_snapshot;
+    cfg.general.me_deterministic_writer_sort = new.general.me_deterministic_writer_sort;
+    cfg.general.me_single_endpoint_shadow_writers = new.general.me_single_endpoint_shadow_writers;
+    cfg.general.me_single_endpoint_outage_mode_enabled =
+        new.general.me_single_endpoint_outage_mode_enabled;
+    cfg.general.me_single_endpoint_outage_disable_quarantine =
+        new.general.me_single_endpoint_outage_disable_quarantine;
+    cfg.general.me_single_endpoint_outage_backoff_min_ms =
+        new.general.me_single_endpoint_outage_backoff_min_ms;
+    cfg.general.me_single_endpoint_outage_backoff_max_ms =
+        new.general.me_single_endpoint_outage_backoff_max_ms;
+    cfg.general.me_single_endpoint_shadow_rotate_every_secs =
+        new.general.me_single_endpoint_shadow_rotate_every_secs;
+    cfg.general.me_config_stable_snapshots = new.general.me_config_stable_snapshots;
+    cfg.general.me_config_apply_cooldown_secs = new.general.me_config_apply_cooldown_secs;
+    cfg.general.me_snapshot_require_http_2xx = new.general.me_snapshot_require_http_2xx;
+    cfg.general.me_snapshot_reject_empty_map = new.general.me_snapshot_reject_empty_map;
+    cfg.general.me_snapshot_min_proxy_for_lines = new.general.me_snapshot_min_proxy_for_lines;
+    cfg.general.proxy_secret_stable_snapshots = new.general.proxy_secret_stable_snapshots;
+    cfg.general.proxy_secret_rotate_runtime = new.general.proxy_secret_rotate_runtime;
+    cfg.general.proxy_secret_len_max = new.general.proxy_secret_len_max;
+    cfg.general.telemetry = new.general.telemetry.clone();
+    cfg.general.me_socks_kdf_policy = new.general.me_socks_kdf_policy;
+    cfg.general.me_floor_mode = new.general.me_floor_mode;
+    cfg.general.me_adaptive_floor_idle_secs = new.general.me_adaptive_floor_idle_secs;
+    cfg.general.me_adaptive_floor_min_writers_single_endpoint =
+        new.general.me_adaptive_floor_min_writers_single_endpoint;
+    cfg.general.me_adaptive_floor_min_writers_multi_endpoint =
+        new.general.me_adaptive_floor_min_writers_multi_endpoint;
+    cfg.general.me_adaptive_floor_recover_grace_secs =
+        new.general.me_adaptive_floor_recover_grace_secs;
+    cfg.general.me_adaptive_floor_writers_per_core_total =
+        new.general.me_adaptive_floor_writers_per_core_total;
+    cfg.general.me_adaptive_floor_cpu_cores_override =
+        new.general.me_adaptive_floor_cpu_cores_override;
+    cfg.general.me_adaptive_floor_max_extra_writers_single_per_core =
+        new.general.me_adaptive_floor_max_extra_writers_single_per_core;
+    cfg.general.me_adaptive_floor_max_extra_writers_multi_per_core =
+        new.general.me_adaptive_floor_max_extra_writers_multi_per_core;
+    cfg.general.me_adaptive_floor_max_active_writers_per_core =
+        new.general.me_adaptive_floor_max_active_writers_per_core;
+    cfg.general.me_adaptive_floor_max_warm_writers_per_core =
+        new.general.me_adaptive_floor_max_warm_writers_per_core;
+    cfg.general.me_adaptive_floor_max_active_writers_global =
+        new.general.me_adaptive_floor_max_active_writers_global;
+    cfg.general.me_adaptive_floor_max_warm_writers_global =
+        new.general.me_adaptive_floor_max_warm_writers_global;
+    cfg.general.me_route_backpressure_base_timeout_ms =
+        new.general.me_route_backpressure_base_timeout_ms;
+    cfg.general.me_route_backpressure_high_timeout_ms =
+        new.general.me_route_backpressure_high_timeout_ms;
+    cfg.general.me_route_backpressure_high_watermark_pct =
+        new.general.me_route_backpressure_high_watermark_pct;
+    cfg.general.me_health_interval_ms_unhealthy = new.general.me_health_interval_ms_unhealthy;
+    cfg.general.me_health_interval_ms_healthy = new.general.me_health_interval_ms_healthy;
+    cfg.general.me_admission_poll_ms = new.general.me_admission_poll_ms;
+    cfg.general.me_warn_rate_limit_ms = new.general.me_warn_rate_limit_ms;
+
+    cfg.access.users = new.access.users.clone();
+    cfg.access.user_ad_tags = new.access.user_ad_tags.clone();
+    cfg.access.user_max_tcp_conns = new.access.user_max_tcp_conns.clone();
+    cfg.access.user_expirations = new.access.user_expirations.clone();
+    cfg.access.user_data_quota = new.access.user_data_quota.clone();
+    cfg.access.user_max_unique_ips = new.access.user_max_unique_ips.clone();
+    cfg.access.user_max_unique_ips_mode = new.access.user_max_unique_ips_mode;
+    cfg.access.user_max_unique_ips_window_secs = new.access.user_max_unique_ips_window_secs;
+
+    cfg
+}
+
 /// Warn if any non-hot fields changed (require restart).
-fn warn_non_hot_changes(old: &ProxyConfig, new: &ProxyConfig) {
+fn warn_non_hot_changes(old: &ProxyConfig, new: &ProxyConfig, non_hot_changed: bool) {
+    let mut warned = false;
     if old.server.port != new.server.port {
+        warned = true;
         warn!(
             "config reload: server.port changed ({} → {}); restart required",
             old.server.port, new.server.port
@@ -123,25 +378,119 @@ fn warn_non_hot_changes(old: &ProxyConfig, new: &ProxyConfig) {
         || old.server.api.minimal_runtime_enabled != new.server.api.minimal_runtime_enabled
         || old.server.api.minimal_runtime_cache_ttl_ms
             != new.server.api.minimal_runtime_cache_ttl_ms
+        || old.server.api.runtime_edge_enabled != new.server.api.runtime_edge_enabled
+        || old.server.api.runtime_edge_cache_ttl_ms
+            != new.server.api.runtime_edge_cache_ttl_ms
+        || old.server.api.runtime_edge_top_n != new.server.api.runtime_edge_top_n
+        || old.server.api.runtime_edge_events_capacity
+            != new.server.api.runtime_edge_events_capacity
         || old.server.api.read_only != new.server.api.read_only
     {
+        warned = true;
         warn!("config reload: server.api changed; restart required");
     }
+    if old.server.proxy_protocol != new.server.proxy_protocol
+        || !listeners_equal(&old.server.listeners, &new.server.listeners)
+        || old.server.listen_addr_ipv4 != new.server.listen_addr_ipv4
+        || old.server.listen_addr_ipv6 != new.server.listen_addr_ipv6
+        || old.server.listen_tcp != new.server.listen_tcp
+        || old.server.listen_unix_sock != new.server.listen_unix_sock
+        || old.server.listen_unix_sock_perm != new.server.listen_unix_sock_perm
+    {
+        warned = true;
+        warn!("config reload: server listener settings changed; restart required");
+    }
+    if old.censorship.tls_domain != new.censorship.tls_domain
+        || old.censorship.tls_domains != new.censorship.tls_domains
+        || old.censorship.mask != new.censorship.mask
+        || old.censorship.mask_host != new.censorship.mask_host
+        || old.censorship.mask_port != new.censorship.mask_port
+        || old.censorship.mask_unix_sock != new.censorship.mask_unix_sock
+        || old.censorship.fake_cert_len != new.censorship.fake_cert_len
+        || old.censorship.tls_emulation != new.censorship.tls_emulation
+        || old.censorship.tls_front_dir != new.censorship.tls_front_dir
+        || old.censorship.server_hello_delay_min_ms != new.censorship.server_hello_delay_min_ms
+        || old.censorship.server_hello_delay_max_ms != new.censorship.server_hello_delay_max_ms
+        || old.censorship.tls_new_session_tickets != new.censorship.tls_new_session_tickets
+        || old.censorship.tls_full_cert_ttl_secs != new.censorship.tls_full_cert_ttl_secs
+        || old.censorship.alpn_enforce != new.censorship.alpn_enforce
+        || old.censorship.mask_proxy_protocol != new.censorship.mask_proxy_protocol
+    {
+        warned = true;
+        warn!("config reload: censorship settings changed; restart required");
+    }
     if old.censorship.tls_domain != new.censorship.tls_domain {
+        warned = true;
         warn!(
             "config reload: censorship.tls_domain changed ('{}' → '{}'); restart required",
             old.censorship.tls_domain, new.censorship.tls_domain
         );
     }
     if old.network.ipv4 != new.network.ipv4 || old.network.ipv6 != new.network.ipv6 {
+        warned = true;
         warn!("config reload: network.ipv4/ipv6 changed; restart required");
     }
+    if old.network.prefer != new.network.prefer
+        || old.network.multipath != new.network.multipath
+        || old.network.stun_use != new.network.stun_use
+        || old.network.stun_servers != new.network.stun_servers
+        || old.network.stun_tcp_fallback != new.network.stun_tcp_fallback
+        || old.network.http_ip_detect_urls != new.network.http_ip_detect_urls
+        || old.network.cache_public_ip_path != new.network.cache_public_ip_path
+    {
+        warned = true;
+        warn!("config reload: non-hot network settings changed; restart required");
+    }
     if old.general.use_middle_proxy != new.general.use_middle_proxy {
+        warned = true;
         warn!("config reload: use_middle_proxy changed; restart required");
     }
     if old.general.stun_nat_probe_concurrency != new.general.stun_nat_probe_concurrency {
+        warned = true;
         warn!("config reload: general.stun_nat_probe_concurrency changed; restart required");
     }
+    if old.general.middle_proxy_pool_size != new.general.middle_proxy_pool_size {
+        warned = true;
+        warn!("config reload: general.middle_proxy_pool_size changed; restart required");
+    }
+    if old.general.me_route_no_writer_mode != new.general.me_route_no_writer_mode
+        || old.general.me_route_no_writer_wait_ms != new.general.me_route_no_writer_wait_ms
+        || old.general.me_route_inline_recovery_attempts
+            != new.general.me_route_inline_recovery_attempts
+        || old.general.me_route_inline_recovery_wait_ms
+            != new.general.me_route_inline_recovery_wait_ms
+    {
+        warned = true;
+        warn!("config reload: general.me_route_no_writer_* changed; restart required");
+    }
+    if old.general.unknown_dc_log_path != new.general.unknown_dc_log_path
+        || old.general.unknown_dc_file_log_enabled != new.general.unknown_dc_file_log_enabled
+    {
+        warned = true;
+        warn!("config reload: general.unknown_dc_* changed; restart required");
+    }
+    if old.general.me_init_retry_attempts != new.general.me_init_retry_attempts {
+        warned = true;
+        warn!("config reload: general.me_init_retry_attempts changed; restart required");
+    }
+    if old.general.me2dc_fallback != new.general.me2dc_fallback {
+        warned = true;
+        warn!("config reload: general.me2dc_fallback changed; restart required");
+    }
+    if old.general.proxy_config_v4_cache_path != new.general.proxy_config_v4_cache_path
+        || old.general.proxy_config_v6_cache_path != new.general.proxy_config_v6_cache_path
+    {
+        warned = true;
+        warn!("config reload: general.proxy_config_*_cache_path changed; restart required");
+    }
+    if old.general.me_keepalive_enabled != new.general.me_keepalive_enabled
+        || old.general.me_keepalive_interval_secs != new.general.me_keepalive_interval_secs
+        || old.general.me_keepalive_jitter_secs != new.general.me_keepalive_jitter_secs
+        || old.general.me_keepalive_payload_random != new.general.me_keepalive_payload_random
+    {
+        warned = true;
+        warn!("config reload: general.me_keepalive_* changed; restart required");
+    }
     if old.general.upstream_connect_retry_attempts != new.general.upstream_connect_retry_attempts
         || old.general.upstream_connect_retry_backoff_ms
             != new.general.upstream_connect_retry_backoff_ms
@@ -151,8 +500,12 @@ fn warn_non_hot_changes(old: &ProxyConfig, new: &ProxyConfig) {
             != new.general.upstream_connect_failfast_hard_errors
         || old.general.rpc_proxy_req_every != new.general.rpc_proxy_req_every
     {
+        warned = true;
         warn!("config reload: general.upstream_* changed; restart required");
     }
+    if non_hot_changed && !warned {
+        warn!("config reload: one or more non-hot fields changed; restart required");
+    }
 }
 
 /// Resolve the public host for link generation — mirrors the logic in main.rs.
@@ -235,10 +588,10 @@ fn log_changes(
         log_tx.send(new_hot.log_level.clone()).ok();
     }
 
-    if old_hot.access.user_ad_tags != new_hot.access.user_ad_tags {
+    if old_hot.user_ad_tags != new_hot.user_ad_tags {
         info!(
             "config reload: user_ad_tags updated ({} entries)",
-            new_hot.access.user_ad_tags.len(),
+            new_hot.user_ad_tags.len(),
         );
     }
 
@@ -253,13 +606,6 @@ fn log_changes(
         );
     }
 
-    if old_hot.middle_proxy_pool_size != new_hot.middle_proxy_pool_size {
-        info!(
-            "config reload: middle_proxy_pool_size: {} → {}",
-            old_hot.middle_proxy_pool_size, new_hot.middle_proxy_pool_size,
-        );
-    }
-
     if old_hot.desync_all_full != new_hot.desync_all_full {
         info!(
             "config reload: desync_all_full: {} → {}",
@@ -273,6 +619,17 @@ fn log_changes(
             old_hot.update_every_secs, new_hot.update_every_secs,
         );
     }
+    if old_hot.me_reinit_every_secs != new_hot.me_reinit_every_secs
+        || old_hot.me_reinit_singleflight != new_hot.me_reinit_singleflight
+        || old_hot.me_reinit_coalesce_window_ms != new_hot.me_reinit_coalesce_window_ms
+    {
+        info!(
+            "config reload: me_reinit: interval={}s singleflight={} coalesce={}ms",
+            new_hot.me_reinit_every_secs,
+            new_hot.me_reinit_singleflight,
+            new_hot.me_reinit_coalesce_window_ms
+        );
+    }
 
     if old_hot.hardswap != new_hot.hardswap {
         info!(
@@ -301,18 +658,84 @@ fn log_changes(
             old_hot.me_reinit_drain_timeout_secs, new_hot.me_reinit_drain_timeout_secs,
         );
     }
-
-    if old_hot.me_keepalive_enabled        != new_hot.me_keepalive_enabled
-    || old_hot.me_keepalive_interval_secs  != new_hot.me_keepalive_interval_secs
-    || old_hot.me_keepalive_jitter_secs    != new_hot.me_keepalive_jitter_secs
-    || old_hot.me_keepalive_payload_random != new_hot.me_keepalive_payload_random
+    if old_hot.me_hardswap_warmup_delay_min_ms != new_hot.me_hardswap_warmup_delay_min_ms
+        || old_hot.me_hardswap_warmup_delay_max_ms != new_hot.me_hardswap_warmup_delay_max_ms
+        || old_hot.me_hardswap_warmup_extra_passes != new_hot.me_hardswap_warmup_extra_passes
+        || old_hot.me_hardswap_warmup_pass_backoff_base_ms
+            != new_hot.me_hardswap_warmup_pass_backoff_base_ms
     {
         info!(
-            "config reload: me_keepalive: enabled={} interval={}s jitter={}s random_payload={}",
-            new_hot.me_keepalive_enabled,
-            new_hot.me_keepalive_interval_secs,
-            new_hot.me_keepalive_jitter_secs,
-            new_hot.me_keepalive_payload_random,
+            "config reload: me_hardswap_warmup: min={}ms max={}ms extra_passes={} pass_backoff={}ms",
+            new_hot.me_hardswap_warmup_delay_min_ms,
+            new_hot.me_hardswap_warmup_delay_max_ms,
+            new_hot.me_hardswap_warmup_extra_passes,
+            new_hot.me_hardswap_warmup_pass_backoff_base_ms
+        );
+    }
+    if old_hot.me_bind_stale_mode != new_hot.me_bind_stale_mode
+        || old_hot.me_bind_stale_ttl_secs != new_hot.me_bind_stale_ttl_secs
+    {
+        info!(
+            "config reload: me_bind_stale: mode={:?} ttl={}s",
+            new_hot.me_bind_stale_mode,
+            new_hot.me_bind_stale_ttl_secs
+        );
+    }
+    if old_hot.me_secret_atomic_snapshot != new_hot.me_secret_atomic_snapshot
+        || old_hot.me_deterministic_writer_sort != new_hot.me_deterministic_writer_sort
+    {
+        info!(
+            "config reload: me_runtime_flags: secret_atomic_snapshot={} deterministic_sort={}",
+            new_hot.me_secret_atomic_snapshot,
+            new_hot.me_deterministic_writer_sort
+        );
+    }
+    if old_hot.me_single_endpoint_shadow_writers != new_hot.me_single_endpoint_shadow_writers
+        || old_hot.me_single_endpoint_outage_mode_enabled
+            != new_hot.me_single_endpoint_outage_mode_enabled
+        || old_hot.me_single_endpoint_outage_disable_quarantine
+            != new_hot.me_single_endpoint_outage_disable_quarantine
+        || old_hot.me_single_endpoint_outage_backoff_min_ms
+            != new_hot.me_single_endpoint_outage_backoff_min_ms
+        || old_hot.me_single_endpoint_outage_backoff_max_ms
+            != new_hot.me_single_endpoint_outage_backoff_max_ms
+        || old_hot.me_single_endpoint_shadow_rotate_every_secs
+            != new_hot.me_single_endpoint_shadow_rotate_every_secs
+    {
+        info!(
+            "config reload: me_single_endpoint: shadow={} outage_enabled={} disable_quarantine={} backoff=[{}..{}]ms rotate={}s",
+            new_hot.me_single_endpoint_shadow_writers,
+            new_hot.me_single_endpoint_outage_mode_enabled,
+            new_hot.me_single_endpoint_outage_disable_quarantine,
+            new_hot.me_single_endpoint_outage_backoff_min_ms,
+            new_hot.me_single_endpoint_outage_backoff_max_ms,
+            new_hot.me_single_endpoint_shadow_rotate_every_secs
+        );
+    }
+    if old_hot.me_config_stable_snapshots != new_hot.me_config_stable_snapshots
+        || old_hot.me_config_apply_cooldown_secs != new_hot.me_config_apply_cooldown_secs
+        || old_hot.me_snapshot_require_http_2xx != new_hot.me_snapshot_require_http_2xx
+        || old_hot.me_snapshot_reject_empty_map != new_hot.me_snapshot_reject_empty_map
+        || old_hot.me_snapshot_min_proxy_for_lines != new_hot.me_snapshot_min_proxy_for_lines
+    {
+        info!(
+            "config reload: me_snapshot_guard: stable={} cooldown={}s require_2xx={} reject_empty={} min_proxy_for={}",
+            new_hot.me_config_stable_snapshots,
+            new_hot.me_config_apply_cooldown_secs,
+            new_hot.me_snapshot_require_http_2xx,
+            new_hot.me_snapshot_reject_empty_map,
+            new_hot.me_snapshot_min_proxy_for_lines
+        );
+    }
+    if old_hot.proxy_secret_stable_snapshots != new_hot.proxy_secret_stable_snapshots
+        || old_hot.proxy_secret_rotate_runtime != new_hot.proxy_secret_rotate_runtime
+        || old_hot.proxy_secret_len_max != new_hot.proxy_secret_len_max
+    {
+        info!(
+            "config reload: proxy_secret_runtime: stable={} rotate={} len_max={}",
+            new_hot.proxy_secret_stable_snapshots,
+            new_hot.proxy_secret_rotate_runtime,
+            new_hot.proxy_secret_len_max
         );
     }
 
@@ -340,15 +763,42 @@ fn log_changes(
         || old_hot.me_adaptive_floor_idle_secs != new_hot.me_adaptive_floor_idle_secs
         || old_hot.me_adaptive_floor_min_writers_single_endpoint
             != new_hot.me_adaptive_floor_min_writers_single_endpoint
+        || old_hot.me_adaptive_floor_min_writers_multi_endpoint
+            != new_hot.me_adaptive_floor_min_writers_multi_endpoint
         || old_hot.me_adaptive_floor_recover_grace_secs
             != new_hot.me_adaptive_floor_recover_grace_secs
+        || old_hot.me_adaptive_floor_writers_per_core_total
+            != new_hot.me_adaptive_floor_writers_per_core_total
+        || old_hot.me_adaptive_floor_cpu_cores_override
+            != new_hot.me_adaptive_floor_cpu_cores_override
+        || old_hot.me_adaptive_floor_max_extra_writers_single_per_core
+            != new_hot.me_adaptive_floor_max_extra_writers_single_per_core
+        || old_hot.me_adaptive_floor_max_extra_writers_multi_per_core
+            != new_hot.me_adaptive_floor_max_extra_writers_multi_per_core
+        || old_hot.me_adaptive_floor_max_active_writers_per_core
+            != new_hot.me_adaptive_floor_max_active_writers_per_core
+        || old_hot.me_adaptive_floor_max_warm_writers_per_core
+            != new_hot.me_adaptive_floor_max_warm_writers_per_core
+        || old_hot.me_adaptive_floor_max_active_writers_global
+            != new_hot.me_adaptive_floor_max_active_writers_global
+        || old_hot.me_adaptive_floor_max_warm_writers_global
+            != new_hot.me_adaptive_floor_max_warm_writers_global
     {
         info!(
-            "config reload: me_floor: mode={:?} idle={}s min_single={} recover_grace={}s",
+            "config reload: me_floor: mode={:?} idle={}s min_single={} min_multi={} recover_grace={}s per_core_total={} cores_override={} extra_single_per_core={} extra_multi_per_core={} max_active_per_core={} max_warm_per_core={} max_active_global={} max_warm_global={}",
             new_hot.me_floor_mode,
             new_hot.me_adaptive_floor_idle_secs,
             new_hot.me_adaptive_floor_min_writers_single_endpoint,
+            new_hot.me_adaptive_floor_min_writers_multi_endpoint,
             new_hot.me_adaptive_floor_recover_grace_secs,
+            new_hot.me_adaptive_floor_writers_per_core_total,
+            new_hot.me_adaptive_floor_cpu_cores_override,
+            new_hot.me_adaptive_floor_max_extra_writers_single_per_core,
+            new_hot.me_adaptive_floor_max_extra_writers_multi_per_core,
+            new_hot.me_adaptive_floor_max_active_writers_per_core,
+            new_hot.me_adaptive_floor_max_warm_writers_per_core,
+            new_hot.me_adaptive_floor_max_active_writers_global,
+            new_hot.me_adaptive_floor_max_warm_writers_global,
         );
     }
 
@@ -358,30 +808,39 @@ fn log_changes(
             != new_hot.me_route_backpressure_high_timeout_ms
         || old_hot.me_route_backpressure_high_watermark_pct
             != new_hot.me_route_backpressure_high_watermark_pct
+        || old_hot.me_health_interval_ms_unhealthy
+            != new_hot.me_health_interval_ms_unhealthy
+        || old_hot.me_health_interval_ms_healthy != new_hot.me_health_interval_ms_healthy
+        || old_hot.me_admission_poll_ms != new_hot.me_admission_poll_ms
+        || old_hot.me_warn_rate_limit_ms != new_hot.me_warn_rate_limit_ms
     {
         info!(
-            "config reload: me_route_backpressure: base={}ms high={}ms watermark={}%",
+            "config reload: me_route_backpressure: base={}ms high={}ms watermark={}%; me_health_interval: unhealthy={}ms healthy={}ms; me_admission_poll={}ms; me_warn_rate_limit={}ms",
             new_hot.me_route_backpressure_base_timeout_ms,
             new_hot.me_route_backpressure_high_timeout_ms,
             new_hot.me_route_backpressure_high_watermark_pct,
+            new_hot.me_health_interval_ms_unhealthy,
+            new_hot.me_health_interval_ms_healthy,
+            new_hot.me_admission_poll_ms,
+            new_hot.me_warn_rate_limit_ms,
         );
     }
 
-    if old_hot.access.users != new_hot.access.users {
-        let mut added: Vec<&String> = new_hot.access.users.keys()
-            .filter(|u| !old_hot.access.users.contains_key(*u))
+    if old_hot.users != new_hot.users {
+        let mut added: Vec<&String> = new_hot.users.keys()
+            .filter(|u| !old_hot.users.contains_key(*u))
             .collect();
         added.sort();
 
-        let mut removed: Vec<&String> = old_hot.access.users.keys()
-            .filter(|u| !new_hot.access.users.contains_key(*u))
+        let mut removed: Vec<&String> = old_hot.users.keys()
+            .filter(|u| !new_hot.users.contains_key(*u))
             .collect();
         removed.sort();
 
-        let mut changed: Vec<&String> = new_hot.access.users.keys()
+        let mut changed: Vec<&String> = new_hot.users.keys()
             .filter(|u| {
-                old_hot.access.users.get(*u)
-                    .map(|s| s != &new_hot.access.users[*u])
+                old_hot.users.get(*u)
+                    .map(|s| s != &new_hot.users[*u])
                     .unwrap_or(false)
             })
             .collect();
@@ -395,7 +854,7 @@ fn log_changes(
             let host = resolve_link_host(new_cfg, detected_ip_v4, detected_ip_v6);
             let port = new_cfg.general.links.public_port.unwrap_or(new_cfg.server.port);
             for user in &added {
-                if let Some(secret) = new_hot.access.users.get(*user) {
+                if let Some(secret) = new_hot.users.get(*user) {
                     print_user_links(user, secret, &host, port, new_cfg);
                 }
             }
@@ -414,28 +873,38 @@ fn log_changes(
         }
     }
 
-    if old_hot.access.user_max_tcp_conns != new_hot.access.user_max_tcp_conns {
+    if old_hot.user_max_tcp_conns != new_hot.user_max_tcp_conns {
         info!(
             "config reload: user_max_tcp_conns updated ({} entries)",
-            new_hot.access.user_max_tcp_conns.len()
+            new_hot.user_max_tcp_conns.len()
         );
     }
-    if old_hot.access.user_expirations != new_hot.access.user_expirations {
+    if old_hot.user_expirations != new_hot.user_expirations {
         info!(
             "config reload: user_expirations updated ({} entries)",
-            new_hot.access.user_expirations.len()
+            new_hot.user_expirations.len()
         );
     }
-    if old_hot.access.user_data_quota != new_hot.access.user_data_quota {
+    if old_hot.user_data_quota != new_hot.user_data_quota {
         info!(
             "config reload: user_data_quota updated ({} entries)",
-            new_hot.access.user_data_quota.len()
+            new_hot.user_data_quota.len()
         );
     }
-    if old_hot.access.user_max_unique_ips != new_hot.access.user_max_unique_ips {
+    if old_hot.user_max_unique_ips != new_hot.user_max_unique_ips {
         info!(
             "config reload: user_max_unique_ips updated ({} entries)",
-            new_hot.access.user_max_unique_ips.len()
+            new_hot.user_max_unique_ips.len()
+        );
+    }
+    if old_hot.user_max_unique_ips_mode != new_hot.user_max_unique_ips_mode
+        || old_hot.user_max_unique_ips_window_secs
+            != new_hot.user_max_unique_ips_window_secs
+    {
+        info!(
+            "config reload: user_max_unique_ips policy mode={:?} window={}s",
+            new_hot.user_max_unique_ips_mode,
+            new_hot.user_max_unique_ips_window_secs
         );
     }
 }
@@ -462,15 +931,22 @@ fn reload_config(
     }
 
     let old_cfg = config_tx.borrow().clone();
+    let applied_cfg = overlay_hot_fields(&old_cfg, &new_cfg);
     let old_hot = HotFields::from_config(&old_cfg);
-    let new_hot = HotFields::from_config(&new_cfg);
+    let applied_hot = HotFields::from_config(&applied_cfg);
+    let non_hot_changed = !config_equal(&applied_cfg, &new_cfg);
+    let hot_changed = old_hot != applied_hot;
 
-    if old_hot == new_hot {
+    if non_hot_changed {
+        warn_non_hot_changes(&old_cfg, &new_cfg, non_hot_changed);
+    }
+
+    if !hot_changed {
         return;
     }
 
-    if old_hot.dns_overrides != new_hot.dns_overrides
-        && let Err(e) = crate::network::dns_overrides::install_entries(&new_hot.dns_overrides)
+    if old_hot.dns_overrides != applied_hot.dns_overrides
+        && let Err(e) = crate::network::dns_overrides::install_entries(&applied_hot.dns_overrides)
     {
         error!(
             "config reload: invalid network.dns_overrides: {}; keeping old config",
@@ -479,9 +955,15 @@ fn reload_config(
         return;
     }
 
-    warn_non_hot_changes(&old_cfg, &new_cfg);
-    log_changes(&old_hot, &new_hot, &new_cfg, log_tx, detected_ip_v4, detected_ip_v6);
-    config_tx.send(Arc::new(new_cfg)).ok();
+    log_changes(
+        &old_hot,
+        &applied_hot,
+        &applied_cfg,
+        log_tx,
+        detected_ip_v4,
+        detected_ip_v6,
+    );
+    config_tx.send(Arc::new(applied_cfg)).ok();
 }
 
 // ── Public API ────────────────────────────────────────────────────────────────
@@ -607,3 +1089,80 @@ pub fn spawn_config_watcher(
 
     (config_rx, log_rx)
 }
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    fn sample_config() -> ProxyConfig {
+        ProxyConfig::default()
+    }
+
+    #[test]
+    fn overlay_applies_hot_and_preserves_non_hot() {
+        let old = sample_config();
+        let mut new = old.clone();
+        new.general.hardswap = !old.general.hardswap;
+        new.server.port = old.server.port.saturating_add(1);
+
+        let applied = overlay_hot_fields(&old, &new);
+        assert_eq!(applied.general.hardswap, new.general.hardswap);
+        assert_eq!(applied.server.port, old.server.port);
+    }
+
+    #[test]
+    fn non_hot_only_change_does_not_change_hot_snapshot() {
+        let old = sample_config();
+        let mut new = old.clone();
+        new.server.port = old.server.port.saturating_add(1);
+
+        let applied = overlay_hot_fields(&old, &new);
+        assert_eq!(HotFields::from_config(&old), HotFields::from_config(&applied));
+        assert_eq!(applied.server.port, old.server.port);
+    }
+
+    #[test]
+    fn bind_stale_mode_is_hot() {
+        let old = sample_config();
+        let mut new = old.clone();
+        new.general.me_bind_stale_mode = match old.general.me_bind_stale_mode {
+            MeBindStaleMode::Never => MeBindStaleMode::Ttl,
+            MeBindStaleMode::Ttl => MeBindStaleMode::Always,
+            MeBindStaleMode::Always => MeBindStaleMode::Never,
+        };
+
+        let applied = overlay_hot_fields(&old, &new);
+        assert_eq!(
+            applied.general.me_bind_stale_mode,
+            new.general.me_bind_stale_mode
+        );
+        assert_ne!(HotFields::from_config(&old), HotFields::from_config(&applied));
+    }
+
+    #[test]
+    fn keepalive_is_not_hot() {
+        let old = sample_config();
+        let mut new = old.clone();
+        new.general.me_keepalive_interval_secs = old.general.me_keepalive_interval_secs + 5;
+
+        let applied = overlay_hot_fields(&old, &new);
+        assert_eq!(
+            applied.general.me_keepalive_interval_secs,
+            old.general.me_keepalive_interval_secs
+        );
+        assert_eq!(HotFields::from_config(&old), HotFields::from_config(&applied));
+    }
+
+    #[test]
+    fn mixed_hot_and_non_hot_change_applies_only_hot_subset() {
+        let old = sample_config();
+        let mut new = old.clone();
+        new.general.hardswap = !old.general.hardswap;
+        new.general.use_middle_proxy = !old.general.use_middle_proxy;
+
+        let applied = overlay_hot_fields(&old, &new);
+        assert_eq!(applied.general.hardswap, new.general.hardswap);
+        assert_eq!(applied.general.use_middle_proxy, old.general.use_middle_proxy);
+        assert!(!config_equal(&applied, &new));
+    }
+}

src/config/load.rs

@@ -203,6 +203,22 @@ impl ProxyConfig {
 
         sanitize_ad_tag(&mut config.general.ad_tag);
 
+        if let Some(path) = &config.general.proxy_config_v4_cache_path
+            && path.trim().is_empty()
+        {
+            return Err(ProxyError::Config(
+                "general.proxy_config_v4_cache_path cannot be empty when provided".to_string(),
+            ));
+        }
+
+        if let Some(path) = &config.general.proxy_config_v6_cache_path
+            && path.trim().is_empty()
+        {
+            return Err(ProxyError::Config(
+                "general.proxy_config_v6_cache_path cannot be empty when provided".to_string(),
+            ));
+        }
+
         if let Some(update_every) = config.general.update_every {
             if update_every == 0 {
                 return Err(ProxyError::Config(
@@ -237,12 +253,24 @@ impl ProxyConfig {
             ));
         }
 
+        if config.general.me_init_retry_attempts > 1_000_000 {
+            return Err(ProxyError::Config(
+                "general.me_init_retry_attempts must be within [0, 1000000]".to_string(),
+            ));
+        }
+
         if config.general.upstream_connect_retry_attempts == 0 {
             return Err(ProxyError::Config(
                 "general.upstream_connect_retry_attempts must be > 0".to_string(),
             ));
         }
 
+        if config.general.upstream_connect_budget_ms == 0 {
+            return Err(ProxyError::Config(
+                "general.upstream_connect_budget_ms must be > 0".to_string(),
+            ));
+        }
+
         if config.general.upstream_unhealthy_fail_threshold == 0 {
             return Err(ProxyError::Config(
                 "general.upstream_unhealthy_fail_threshold must be > 0".to_string(),
@@ -257,6 +285,54 @@ impl ProxyConfig {
             ));
         }
 
+        if config.general.me_writer_cmd_channel_capacity == 0 {
+            return Err(ProxyError::Config(
+                "general.me_writer_cmd_channel_capacity must be > 0".to_string(),
+            ));
+        }
+
+        if config.general.me_route_channel_capacity == 0 {
+            return Err(ProxyError::Config(
+                "general.me_route_channel_capacity must be > 0".to_string(),
+            ));
+        }
+
+        if config.general.me_c2me_channel_capacity == 0 {
+            return Err(ProxyError::Config(
+                "general.me_c2me_channel_capacity must be > 0".to_string(),
+            ));
+        }
+
+        if config.general.me_health_interval_ms_unhealthy == 0 {
+            return Err(ProxyError::Config(
+                "general.me_health_interval_ms_unhealthy must be > 0".to_string(),
+            ));
+        }
+
+        if config.general.me_health_interval_ms_healthy == 0 {
+            return Err(ProxyError::Config(
+                "general.me_health_interval_ms_healthy must be > 0".to_string(),
+            ));
+        }
+
+        if config.general.me_admission_poll_ms == 0 {
+            return Err(ProxyError::Config(
+                "general.me_admission_poll_ms must be > 0".to_string(),
+            ));
+        }
+
+        if config.general.me_warn_rate_limit_ms == 0 {
+            return Err(ProxyError::Config(
+                "general.me_warn_rate_limit_ms must be > 0".to_string(),
+            ));
+        }
+
+        if config.access.user_max_unique_ips_window_secs == 0 {
+            return Err(ProxyError::Config(
+                "access.user_max_unique_ips_window_secs must be > 0".to_string(),
+            ));
+        }
+
         if config.general.me_reinit_every_secs == 0 {
             return Err(ProxyError::Config(
                 "general.me_reinit_every_secs must be > 0".to_string(),
@@ -278,6 +354,45 @@ impl ProxyConfig {
             ));
         }
 
+        if config.general.me_adaptive_floor_min_writers_multi_endpoint == 0
+            || config.general.me_adaptive_floor_min_writers_multi_endpoint > 32
+        {
+            return Err(ProxyError::Config(
+                "general.me_adaptive_floor_min_writers_multi_endpoint must be within [1, 32]"
+                    .to_string(),
+            ));
+        }
+
+        if config.general.me_adaptive_floor_writers_per_core_total == 0 {
+            return Err(ProxyError::Config(
+                "general.me_adaptive_floor_writers_per_core_total must be > 0".to_string(),
+            ));
+        }
+
+        if config.general.me_adaptive_floor_max_active_writers_per_core == 0 {
+            return Err(ProxyError::Config(
+                "general.me_adaptive_floor_max_active_writers_per_core must be > 0".to_string(),
+            ));
+        }
+
+        if config.general.me_adaptive_floor_max_warm_writers_per_core == 0 {
+            return Err(ProxyError::Config(
+                "general.me_adaptive_floor_max_warm_writers_per_core must be > 0".to_string(),
+            ));
+        }
+
+        if config.general.me_adaptive_floor_max_active_writers_global == 0 {
+            return Err(ProxyError::Config(
+                "general.me_adaptive_floor_max_active_writers_global must be > 0".to_string(),
+            ));
+        }
+
+        if config.general.me_adaptive_floor_max_warm_writers_global == 0 {
+            return Err(ProxyError::Config(
+                "general.me_adaptive_floor_max_warm_writers_global must be > 0".to_string(),
+            ));
+        }
+
         if config.general.me_single_endpoint_outage_backoff_min_ms == 0 {
             return Err(ProxyError::Config(
                 "general.me_single_endpoint_outage_backoff_min_ms must be > 0".to_string(),
@@ -398,6 +513,24 @@ impl ProxyConfig {
             ));
         }
 
+        if !(10..=5000).contains(&config.general.me_route_no_writer_wait_ms) {
+            return Err(ProxyError::Config(
+                "general.me_route_no_writer_wait_ms must be within [10, 5000]".to_string(),
+            ));
+        }
+
+        if config.general.me_route_inline_recovery_attempts == 0 {
+            return Err(ProxyError::Config(
+                "general.me_route_inline_recovery_attempts must be > 0".to_string(),
+            ));
+        }
+
+        if !(10..=30000).contains(&config.general.me_route_inline_recovery_wait_ms) {
+            return Err(ProxyError::Config(
+                "general.me_route_inline_recovery_wait_ms must be within [10, 30000]".to_string(),
+            ));
+        }
+
         if config.server.api.request_body_limit_bytes == 0 {
             return Err(ProxyError::Config(
                 "server.api.request_body_limit_bytes must be > 0".to_string(),
@@ -410,12 +543,36 @@ impl ProxyConfig {
             ));
         }
 
+        if config.server.api.runtime_edge_cache_ttl_ms > 60_000 {
+            return Err(ProxyError::Config(
+                "server.api.runtime_edge_cache_ttl_ms must be within [0, 60000]".to_string(),
+            ));
+        }
+
+        if !(1..=1000).contains(&config.server.api.runtime_edge_top_n) {
+            return Err(ProxyError::Config(
+                "server.api.runtime_edge_top_n must be within [1, 1000]".to_string(),
+            ));
+        }
+
+        if !(16..=4096).contains(&config.server.api.runtime_edge_events_capacity) {
+            return Err(ProxyError::Config(
+                "server.api.runtime_edge_events_capacity must be within [16, 4096]".to_string(),
+            ));
+        }
+
         if config.server.api.listen.parse::<SocketAddr>().is_err() {
             return Err(ProxyError::Config(
                 "server.api.listen must be in IP:PORT format".to_string(),
             ));
         }
 
+        if config.server.proxy_protocol_header_timeout_ms == 0 {
+            return Err(ProxyError::Config(
+                "server.proxy_protocol_header_timeout_ms must be > 0".to_string(),
+            ));
+        }
+
         if config.general.effective_me_pool_force_close_secs() > 0
             && config.general.effective_me_pool_force_close_secs()
                 < config.general.me_pool_drain_ttl_secs
@@ -497,10 +654,11 @@ impl ProxyConfig {
             warn!("prefer_ipv6 is deprecated, use [network].prefer = 6");
         }
 
-        // Auto-enable NAT probe when Middle Proxy is requested.
-        if config.general.use_middle_proxy && !config.general.middle_proxy_nat_probe {
-            config.general.middle_proxy_nat_probe = true;
-            warn!("Auto-enabled middle_proxy_nat_probe for middle proxy mode");
+        if config.general.use_middle_proxy && !config.general.me_secret_atomic_snapshot {
+            config.general.me_secret_atomic_snapshot = true;
+            warn!(
+                "Auto-enabled me_secret_atomic_snapshot for middle proxy mode to keep KDF key_selector/secret coherent"
+            );
         }
 
         validate_network_cfg(&mut config.network)?;
@@ -653,6 +811,22 @@ mod tests {
             cfg.general.me_reconnect_fast_retry_count,
             default_me_reconnect_fast_retry_count()
         );
+        assert_eq!(
+            cfg.general.me_init_retry_attempts,
+            default_me_init_retry_attempts()
+        );
+        assert_eq!(
+            cfg.general.me2dc_fallback,
+            default_me2dc_fallback()
+        );
+        assert_eq!(
+            cfg.general.proxy_config_v4_cache_path,
+            default_proxy_config_v4_cache_path()
+        );
+        assert_eq!(
+            cfg.general.proxy_config_v6_cache_path,
+            default_proxy_config_v6_cache_path()
+        );
         assert_eq!(
             cfg.general.me_single_endpoint_shadow_writers,
             default_me_single_endpoint_shadow_writers()
@@ -727,7 +901,31 @@ mod tests {
             cfg.server.api.minimal_runtime_cache_ttl_ms,
             default_api_minimal_runtime_cache_ttl_ms()
         );
+        assert_eq!(
+            cfg.server.api.runtime_edge_enabled,
+            default_api_runtime_edge_enabled()
+        );
+        assert_eq!(
+            cfg.server.api.runtime_edge_cache_ttl_ms,
+            default_api_runtime_edge_cache_ttl_ms()
+        );
+        assert_eq!(
+            cfg.server.api.runtime_edge_top_n,
+            default_api_runtime_edge_top_n()
+        );
+        assert_eq!(
+            cfg.server.api.runtime_edge_events_capacity,
+            default_api_runtime_edge_events_capacity()
+        );
         assert_eq!(cfg.access.users, default_access_users());
+        assert_eq!(
+            cfg.access.user_max_unique_ips_mode,
+            UserMaxUniqueIpsMode::default()
+        );
+        assert_eq!(
+            cfg.access.user_max_unique_ips_window_secs,
+            default_user_max_unique_ips_window_secs()
+        );
     }
 
     #[test]
@@ -750,6 +948,19 @@ mod tests {
             general.me_reconnect_fast_retry_count,
             default_me_reconnect_fast_retry_count()
         );
+        assert_eq!(
+            general.me_init_retry_attempts,
+            default_me_init_retry_attempts()
+        );
+        assert_eq!(general.me2dc_fallback, default_me2dc_fallback());
+        assert_eq!(
+            general.proxy_config_v4_cache_path,
+            default_proxy_config_v4_cache_path()
+        );
+        assert_eq!(
+            general.proxy_config_v6_cache_path,
+            default_proxy_config_v6_cache_path()
+        );
         assert_eq!(
             general.me_single_endpoint_shadow_writers,
             default_me_single_endpoint_shadow_writers()
@@ -822,6 +1033,22 @@ mod tests {
             server.api.minimal_runtime_cache_ttl_ms,
             default_api_minimal_runtime_cache_ttl_ms()
         );
+        assert_eq!(
+            server.api.runtime_edge_enabled,
+            default_api_runtime_edge_enabled()
+        );
+        assert_eq!(
+            server.api.runtime_edge_cache_ttl_ms,
+            default_api_runtime_edge_cache_ttl_ms()
+        );
+        assert_eq!(
+            server.api.runtime_edge_top_n,
+            default_api_runtime_edge_top_n()
+        );
+        assert_eq!(
+            server.api.runtime_edge_events_capacity,
+            default_api_runtime_edge_events_capacity()
+        );
 
         let access = AccessConfig::default();
         assert_eq!(access.users, default_access_users());
@@ -1077,6 +1304,46 @@ mod tests {
         let _ = std::fs::remove_file(path);
     }
 
+    #[test]
+    fn me_adaptive_floor_max_active_writers_per_core_zero_is_rejected() {
+        let toml = r#"
+            [general]
+            me_adaptive_floor_max_active_writers_per_core = 0
+
+            [censorship]
+            tls_domain = "example.com"
+
+            [access.users]
+            user = "00000000000000000000000000000000"
+        "#;
+        let dir = std::env::temp_dir();
+        let path = dir.join("telemt_me_adaptive_floor_max_active_per_core_zero_test.toml");
+        std::fs::write(&path, toml).unwrap();
+        let err = ProxyConfig::load(&path).unwrap_err().to_string();
+        assert!(err.contains("general.me_adaptive_floor_max_active_writers_per_core must be > 0"));
+        let _ = std::fs::remove_file(path);
+    }
+
+    #[test]
+    fn me_adaptive_floor_max_warm_writers_global_zero_is_rejected() {
+        let toml = r#"
+            [general]
+            me_adaptive_floor_max_warm_writers_global = 0
+
+            [censorship]
+            tls_domain = "example.com"
+
+            [access.users]
+            user = "00000000000000000000000000000000"
+        "#;
+        let dir = std::env::temp_dir();
+        let path = dir.join("telemt_me_adaptive_floor_max_warm_global_zero_test.toml");
+        std::fs::write(&path, toml).unwrap();
+        let err = ProxyConfig::load(&path).unwrap_err().to_string();
+        assert!(err.contains("general.me_adaptive_floor_max_warm_writers_global must be > 0"));
+        let _ = std::fs::remove_file(path);
+    }
+
     #[test]
     fn upstream_connect_retry_attempts_zero_is_rejected() {
         let toml = r#"
@@ -1173,6 +1440,85 @@ mod tests {
         let _ = std::fs::remove_file(path_valid);
     }
 
+    #[test]
+    fn me_route_no_writer_wait_ms_out_of_range_is_rejected() {
+        let toml = r#"
+            [general]
+            me_route_no_writer_wait_ms = 5
+
+            [censorship]
+            tls_domain = "example.com"
+
+            [access.users]
+            user = "00000000000000000000000000000000"
+        "#;
+        let dir = std::env::temp_dir();
+        let path = dir.join("telemt_me_route_no_writer_wait_ms_out_of_range_test.toml");
+        std::fs::write(&path, toml).unwrap();
+        let err = ProxyConfig::load(&path).unwrap_err().to_string();
+        assert!(err.contains("general.me_route_no_writer_wait_ms must be within [10, 5000]"));
+        let _ = std::fs::remove_file(path);
+    }
+
+    #[test]
+    fn me_route_no_writer_mode_is_parsed() {
+        let toml = r#"
+            [general]
+            me_route_no_writer_mode = "inline_recovery_legacy"
+
+            [censorship]
+            tls_domain = "example.com"
+
+            [access.users]
+            user = "00000000000000000000000000000000"
+        "#;
+        let dir = std::env::temp_dir();
+        let path = dir.join("telemt_me_route_no_writer_mode_parse_test.toml");
+        std::fs::write(&path, toml).unwrap();
+        let cfg = ProxyConfig::load(&path).unwrap();
+        assert_eq!(
+            cfg.general.me_route_no_writer_mode,
+            crate::config::MeRouteNoWriterMode::InlineRecoveryLegacy
+        );
+        let _ = std::fs::remove_file(path);
+    }
+
+    #[test]
+    fn proxy_config_cache_paths_empty_are_rejected() {
+        let toml = r#"
+            [general]
+            proxy_config_v4_cache_path = "   "
+
+            [censorship]
+            tls_domain = "example.com"
+
+            [access.users]
+            user = "00000000000000000000000000000000"
+        "#;
+        let dir = std::env::temp_dir();
+        let path = dir.join("telemt_proxy_config_v4_cache_path_empty_test.toml");
+        std::fs::write(&path, toml).unwrap();
+        let err = ProxyConfig::load(&path).unwrap_err().to_string();
+        assert!(err.contains("general.proxy_config_v4_cache_path cannot be empty"));
+        let _ = std::fs::remove_file(path);
+
+        let toml_v6 = r#"
+            [general]
+            proxy_config_v6_cache_path = ""
+
+            [censorship]
+            tls_domain = "example.com"
+
+            [access.users]
+            user = "00000000000000000000000000000000"
+        "#;
+        let path_v6 = dir.join("telemt_proxy_config_v6_cache_path_empty_test.toml");
+        std::fs::write(&path_v6, toml_v6).unwrap();
+        let err_v6 = ProxyConfig::load(&path_v6).unwrap_err().to_string();
+        assert!(err_v6.contains("general.proxy_config_v6_cache_path cannot be empty"));
+        let _ = std::fs::remove_file(path_v6);
+    }
+
     #[test]
     fn me_hardswap_warmup_defaults_are_set() {
         let toml = r#"
@@ -1390,6 +1736,72 @@ mod tests {
         let _ = std::fs::remove_file(path);
     }
 
+    #[test]
+    fn api_runtime_edge_cache_ttl_out_of_range_is_rejected() {
+        let toml = r#"
+            [server.api]
+            enabled = true
+            listen = "127.0.0.1:9091"
+            runtime_edge_cache_ttl_ms = 70000
+
+            [censorship]
+            tls_domain = "example.com"
+
+            [access.users]
+            user = "00000000000000000000000000000000"
+        "#;
+        let dir = std::env::temp_dir();
+        let path = dir.join("telemt_api_runtime_edge_cache_ttl_invalid_test.toml");
+        std::fs::write(&path, toml).unwrap();
+        let err = ProxyConfig::load(&path).unwrap_err().to_string();
+        assert!(err.contains("server.api.runtime_edge_cache_ttl_ms must be within [0, 60000]"));
+        let _ = std::fs::remove_file(path);
+    }
+
+    #[test]
+    fn api_runtime_edge_top_n_out_of_range_is_rejected() {
+        let toml = r#"
+            [server.api]
+            enabled = true
+            listen = "127.0.0.1:9091"
+            runtime_edge_top_n = 0
+
+            [censorship]
+            tls_domain = "example.com"
+
+            [access.users]
+            user = "00000000000000000000000000000000"
+        "#;
+        let dir = std::env::temp_dir();
+        let path = dir.join("telemt_api_runtime_edge_top_n_invalid_test.toml");
+        std::fs::write(&path, toml).unwrap();
+        let err = ProxyConfig::load(&path).unwrap_err().to_string();
+        assert!(err.contains("server.api.runtime_edge_top_n must be within [1, 1000]"));
+        let _ = std::fs::remove_file(path);
+    }
+
+    #[test]
+    fn api_runtime_edge_events_capacity_out_of_range_is_rejected() {
+        let toml = r#"
+            [server.api]
+            enabled = true
+            listen = "127.0.0.1:9091"
+            runtime_edge_events_capacity = 8
+
+            [censorship]
+            tls_domain = "example.com"
+
+            [access.users]
+            user = "00000000000000000000000000000000"
+        "#;
+        let dir = std::env::temp_dir();
+        let path = dir.join("telemt_api_runtime_edge_events_capacity_invalid_test.toml");
+        std::fs::write(&path, toml).unwrap();
+        let err = ProxyConfig::load(&path).unwrap_err().to_string();
+        assert!(err.contains("server.api.runtime_edge_events_capacity must be within [16, 4096]"));
+        let _ = std::fs::remove_file(path);
+    }
+
     #[test]
     fn force_close_bumped_when_below_drain_ttl() {
         let toml = r#"

src/config/types.rs

@@ -183,6 +183,48 @@ impl MeFloorMode {
     }
 }
 
+/// Middle-End route behavior when no writer is immediately available.
+#[derive(Debug, Clone, Copy, PartialEq, Eq, Serialize, Deserialize, Default)]
+#[serde(rename_all = "snake_case")]
+pub enum MeRouteNoWriterMode {
+    AsyncRecoveryFailfast,
+    InlineRecoveryLegacy,
+    #[default]
+    HybridAsyncPersistent,
+}
+
+impl MeRouteNoWriterMode {
+    pub fn as_u8(self) -> u8 {
+        match self {
+            MeRouteNoWriterMode::AsyncRecoveryFailfast => 0,
+            MeRouteNoWriterMode::InlineRecoveryLegacy => 1,
+            MeRouteNoWriterMode::HybridAsyncPersistent => 2,
+        }
+    }
+
+    pub fn from_u8(raw: u8) -> Self {
+        match raw {
+            0 => MeRouteNoWriterMode::AsyncRecoveryFailfast,
+            1 => MeRouteNoWriterMode::InlineRecoveryLegacy,
+            2 => MeRouteNoWriterMode::HybridAsyncPersistent,
+            _ => MeRouteNoWriterMode::HybridAsyncPersistent,
+        }
+    }
+}
+
+/// Per-user unique source IP limit mode.
+#[derive(Debug, Clone, Copy, PartialEq, Eq, Serialize, Deserialize, Default)]
+#[serde(rename_all = "snake_case")]
+pub enum UserMaxUniqueIpsMode {
+    /// Count only currently active source IPs.
+    #[default]
+    ActiveWindow,
+    /// Count source IPs seen within the recent time window.
+    TimeWindow,
+    /// Enforce both active and recent-window limits at the same time.
+    Combined,
+}
+
 /// Telemetry controls for hot-path counters and ME diagnostics.
 #[derive(Debug, Clone, PartialEq, Eq, Serialize, Deserialize)]
 pub struct TelemetryConfig {
@@ -305,6 +347,14 @@ pub struct GeneralConfig {
     #[serde(default = "default_proxy_secret_path")]
     pub proxy_secret_path: Option<String>,
 
+    /// Optional path to cache raw getProxyConfig (IPv4) snapshot for startup fallback.
+    #[serde(default = "default_proxy_config_v4_cache_path")]
+    pub proxy_config_v4_cache_path: Option<String>,
+
+    /// Optional path to cache raw getProxyConfigV6 snapshot for startup fallback.
+    #[serde(default = "default_proxy_config_v6_cache_path")]
+    pub proxy_config_v6_cache_path: Option<String>,
+
     /// Global ad_tag (32 hex chars from @MTProxybot). Fallback when user has no per-user tag in access.user_ad_tags.
     #[serde(default)]
     pub ad_tag: Option<String>,
@@ -340,6 +390,15 @@ pub struct GeneralConfig {
     #[serde(default = "default_middle_proxy_warm_standby")]
     pub middle_proxy_warm_standby: usize,
 
+    /// Startup retries for Middle-End pool initialization before ME→Direct fallback.
+    /// 0 means unlimited retries.
+    #[serde(default = "default_me_init_retry_attempts")]
+    pub me_init_retry_attempts: u32,
+
+    /// Allow fallback from Middle-End mode to direct DC when ME startup cannot be initialized.
+    #[serde(default = "default_me2dc_fallback")]
+    pub me2dc_fallback: bool,
+
     /// Enable ME keepalive padding frames.
     #[serde(default = "default_true")]
     pub me_keepalive_enabled: bool,
@@ -361,6 +420,18 @@ pub struct GeneralConfig {
     #[serde(default = "default_rpc_proxy_req_every")]
     pub rpc_proxy_req_every: u64,
 
+    /// Capacity of per-ME writer command channel.
+    #[serde(default = "default_me_writer_cmd_channel_capacity")]
+    pub me_writer_cmd_channel_capacity: usize,
+
+    /// Capacity of per-connection ME response route channel.
+    #[serde(default = "default_me_route_channel_capacity")]
+    pub me_route_channel_capacity: usize,
+
+    /// Capacity of per-client command queue from client reader to ME sender task.
+    #[serde(default = "default_me_c2me_channel_capacity")]
+    pub me_c2me_channel_capacity: usize,
+
     /// Max pending ciphertext buffer per client writer (bytes).
     /// Controls FakeTLS backpressure vs throughput.
     #[serde(default = "default_crypto_pending_buffer")]
@@ -461,10 +532,47 @@ pub struct GeneralConfig {
     #[serde(default = "default_me_adaptive_floor_min_writers_single_endpoint")]
     pub me_adaptive_floor_min_writers_single_endpoint: u8,
 
+    /// Minimum writer target for multi-endpoint DC groups in adaptive floor mode.
+    #[serde(default = "default_me_adaptive_floor_min_writers_multi_endpoint")]
+    pub me_adaptive_floor_min_writers_multi_endpoint: u8,
+
     /// Grace period in seconds to hold static floor after activity in adaptive mode.
     #[serde(default = "default_me_adaptive_floor_recover_grace_secs")]
     pub me_adaptive_floor_recover_grace_secs: u64,
 
+    /// Global ME writer budget per logical CPU core in adaptive mode.
+    #[serde(default = "default_me_adaptive_floor_writers_per_core_total")]
+    pub me_adaptive_floor_writers_per_core_total: u16,
+
+    /// Override logical CPU core count for adaptive floor calculations.
+    /// Set to 0 to use runtime auto-detection.
+    #[serde(default = "default_me_adaptive_floor_cpu_cores_override")]
+    pub me_adaptive_floor_cpu_cores_override: u16,
+
+    /// Per-core max extra writers above base required floor for single-endpoint DC groups.
+    #[serde(default = "default_me_adaptive_floor_max_extra_writers_single_per_core")]
+    pub me_adaptive_floor_max_extra_writers_single_per_core: u16,
+
+    /// Per-core max extra writers above base required floor for multi-endpoint DC groups.
+    #[serde(default = "default_me_adaptive_floor_max_extra_writers_multi_per_core")]
+    pub me_adaptive_floor_max_extra_writers_multi_per_core: u16,
+
+    /// Hard cap for active ME writers per logical CPU core.
+    #[serde(default = "default_me_adaptive_floor_max_active_writers_per_core")]
+    pub me_adaptive_floor_max_active_writers_per_core: u16,
+
+    /// Hard cap for warm ME writers per logical CPU core.
+    #[serde(default = "default_me_adaptive_floor_max_warm_writers_per_core")]
+    pub me_adaptive_floor_max_warm_writers_per_core: u16,
+
+    /// Hard global cap for active ME writers.
+    #[serde(default = "default_me_adaptive_floor_max_active_writers_global")]
+    pub me_adaptive_floor_max_active_writers_global: u32,
+
+    /// Hard global cap for warm ME writers.
+    #[serde(default = "default_me_adaptive_floor_max_warm_writers_global")]
+    pub me_adaptive_floor_max_warm_writers_global: u32,
+
     /// Connect attempts for the selected upstream before returning error/fallback.
     #[serde(default = "default_upstream_connect_retry_attempts")]
     pub upstream_connect_retry_attempts: u32,
@@ -473,6 +581,10 @@ pub struct GeneralConfig {
     #[serde(default = "default_upstream_connect_retry_backoff_ms")]
     pub upstream_connect_retry_backoff_ms: u64,
 
+    /// Total wall-clock budget in milliseconds for one upstream connect request across retries.
+    #[serde(default = "default_upstream_connect_budget_ms")]
+    pub upstream_connect_budget_ms: u64,
+
     /// Consecutive failed requests before upstream is marked unhealthy.
     #[serde(default = "default_upstream_unhealthy_fail_threshold")]
     pub upstream_unhealthy_fail_threshold: u32,
@@ -489,6 +601,10 @@ pub struct GeneralConfig {
     #[serde(default = "default_unknown_dc_log_path")]
     pub unknown_dc_log_path: Option<String>,
 
+    /// Enable unknown-DC file logging.
+    #[serde(default = "default_unknown_dc_file_log_enabled")]
+    pub unknown_dc_file_log_enabled: bool,
+
     #[serde(default)]
     pub log_level: LogLevel,
 
@@ -516,6 +632,38 @@ pub struct GeneralConfig {
     #[serde(default = "default_me_route_backpressure_high_watermark_pct")]
     pub me_route_backpressure_high_watermark_pct: u8,
 
+    /// Health monitor interval in milliseconds while writer coverage is degraded.
+    #[serde(default = "default_me_health_interval_ms_unhealthy")]
+    pub me_health_interval_ms_unhealthy: u64,
+
+    /// Health monitor interval in milliseconds while writer coverage is stable.
+    #[serde(default = "default_me_health_interval_ms_healthy")]
+    pub me_health_interval_ms_healthy: u64,
+
+    /// Poll interval in milliseconds for conditional-admission state checks.
+    #[serde(default = "default_me_admission_poll_ms")]
+    pub me_admission_poll_ms: u64,
+
+    /// Cooldown for repetitive ME warning logs in milliseconds.
+    #[serde(default = "default_me_warn_rate_limit_ms")]
+    pub me_warn_rate_limit_ms: u64,
+
+    /// ME route behavior when no writer is immediately available.
+    #[serde(default)]
+    pub me_route_no_writer_mode: MeRouteNoWriterMode,
+
+    /// Maximum wait time in milliseconds for async-recovery failfast mode.
+    #[serde(default = "default_me_route_no_writer_wait_ms")]
+    pub me_route_no_writer_wait_ms: u64,
+
+    /// Number of inline recovery attempts in legacy mode.
+    #[serde(default = "default_me_route_inline_recovery_attempts")]
+    pub me_route_inline_recovery_attempts: u32,
+
+    /// Maximum wait time in milliseconds for inline recovery in legacy mode.
+    #[serde(default = "default_me_route_inline_recovery_wait_ms")]
+    pub me_route_inline_recovery_wait_ms: u64,
+
     /// [general.links] — proxy link generation overrides.
     #[serde(default)]
     pub links: LinksConfig,
@@ -660,6 +808,8 @@ impl Default for GeneralConfig {
             use_middle_proxy: default_true(),
             ad_tag: None,
             proxy_secret_path: default_proxy_secret_path(),
+            proxy_config_v4_cache_path: default_proxy_config_v4_cache_path(),
+            proxy_config_v6_cache_path: default_proxy_config_v6_cache_path(),
             middle_proxy_nat_ip: None,
             middle_proxy_nat_probe: default_true(),
             middle_proxy_nat_stun: default_middle_proxy_nat_stun(),
@@ -667,11 +817,16 @@ impl Default for GeneralConfig {
             stun_nat_probe_concurrency: default_stun_nat_probe_concurrency(),
             middle_proxy_pool_size: default_pool_size(),
             middle_proxy_warm_standby: default_middle_proxy_warm_standby(),
+            me_init_retry_attempts: default_me_init_retry_attempts(),
+            me2dc_fallback: default_me2dc_fallback(),
             me_keepalive_enabled: default_true(),
             me_keepalive_interval_secs: default_keepalive_interval(),
             me_keepalive_jitter_secs: default_keepalive_jitter(),
             me_keepalive_payload_random: default_true(),
             rpc_proxy_req_every: default_rpc_proxy_req_every(),
+            me_writer_cmd_channel_capacity: default_me_writer_cmd_channel_capacity(),
+            me_route_channel_capacity: default_me_route_channel_capacity(),
+            me_c2me_channel_capacity: default_me_c2me_channel_capacity(),
             me_warmup_stagger_enabled: default_true(),
             me_warmup_step_delay_ms: default_warmup_step_delay_ms(),
             me_warmup_step_jitter_ms: default_warmup_step_jitter_ms(),
@@ -688,13 +843,24 @@ impl Default for GeneralConfig {
             me_floor_mode: MeFloorMode::default(),
             me_adaptive_floor_idle_secs: default_me_adaptive_floor_idle_secs(),
             me_adaptive_floor_min_writers_single_endpoint: default_me_adaptive_floor_min_writers_single_endpoint(),
+            me_adaptive_floor_min_writers_multi_endpoint: default_me_adaptive_floor_min_writers_multi_endpoint(),
             me_adaptive_floor_recover_grace_secs: default_me_adaptive_floor_recover_grace_secs(),
+            me_adaptive_floor_writers_per_core_total: default_me_adaptive_floor_writers_per_core_total(),
+            me_adaptive_floor_cpu_cores_override: default_me_adaptive_floor_cpu_cores_override(),
+            me_adaptive_floor_max_extra_writers_single_per_core: default_me_adaptive_floor_max_extra_writers_single_per_core(),
+            me_adaptive_floor_max_extra_writers_multi_per_core: default_me_adaptive_floor_max_extra_writers_multi_per_core(),
+            me_adaptive_floor_max_active_writers_per_core: default_me_adaptive_floor_max_active_writers_per_core(),
+            me_adaptive_floor_max_warm_writers_per_core: default_me_adaptive_floor_max_warm_writers_per_core(),
+            me_adaptive_floor_max_active_writers_global: default_me_adaptive_floor_max_active_writers_global(),
+            me_adaptive_floor_max_warm_writers_global: default_me_adaptive_floor_max_warm_writers_global(),
             upstream_connect_retry_attempts: default_upstream_connect_retry_attempts(),
             upstream_connect_retry_backoff_ms: default_upstream_connect_retry_backoff_ms(),
+            upstream_connect_budget_ms: default_upstream_connect_budget_ms(),
             upstream_unhealthy_fail_threshold: default_upstream_unhealthy_fail_threshold(),
             upstream_connect_failfast_hard_errors: default_upstream_connect_failfast_hard_errors(),
             stun_iface_mismatch_ignore: false,
             unknown_dc_log_path: default_unknown_dc_log_path(),
+            unknown_dc_file_log_enabled: default_unknown_dc_file_log_enabled(),
             log_level: LogLevel::Normal,
             disable_colors: false,
             telemetry: TelemetryConfig::default(),
@@ -702,6 +868,14 @@ impl Default for GeneralConfig {
             me_route_backpressure_base_timeout_ms: default_me_route_backpressure_base_timeout_ms(),
             me_route_backpressure_high_timeout_ms: default_me_route_backpressure_high_timeout_ms(),
             me_route_backpressure_high_watermark_pct: default_me_route_backpressure_high_watermark_pct(),
+            me_health_interval_ms_unhealthy: default_me_health_interval_ms_unhealthy(),
+            me_health_interval_ms_healthy: default_me_health_interval_ms_healthy(),
+            me_admission_poll_ms: default_me_admission_poll_ms(),
+            me_warn_rate_limit_ms: default_me_warn_rate_limit_ms(),
+            me_route_no_writer_mode: MeRouteNoWriterMode::default(),
+            me_route_no_writer_wait_ms: default_me_route_no_writer_wait_ms(),
+            me_route_inline_recovery_attempts: default_me_route_inline_recovery_attempts(),
+            me_route_inline_recovery_wait_ms: default_me_route_inline_recovery_wait_ms(),
             links: LinksConfig::default(),
             crypto_pending_buffer: default_crypto_pending_buffer(),
             max_client_frame: default_max_client_frame(),
@@ -825,6 +999,22 @@ pub struct ApiConfig {
     #[serde(default = "default_api_minimal_runtime_cache_ttl_ms")]
     pub minimal_runtime_cache_ttl_ms: u64,
 
+    /// Enables runtime edge endpoints with optional cached aggregation.
+    #[serde(default = "default_api_runtime_edge_enabled")]
+    pub runtime_edge_enabled: bool,
+
+    /// Cache TTL for runtime edge aggregation payloads in milliseconds.
+    #[serde(default = "default_api_runtime_edge_cache_ttl_ms")]
+    pub runtime_edge_cache_ttl_ms: u64,
+
+    /// Top-N limit for edge connection leaderboard payloads.
+    #[serde(default = "default_api_runtime_edge_top_n")]
+    pub runtime_edge_top_n: usize,
+
+    /// Ring-buffer capacity for runtime edge control-plane events.
+    #[serde(default = "default_api_runtime_edge_events_capacity")]
+    pub runtime_edge_events_capacity: usize,
+
     /// Read-only mode: mutating endpoints are rejected.
     #[serde(default)]
     pub read_only: bool,
@@ -840,6 +1030,10 @@ impl Default for ApiConfig {
             request_body_limit_bytes: default_api_request_body_limit_bytes(),
             minimal_runtime_enabled: default_api_minimal_runtime_enabled(),
             minimal_runtime_cache_ttl_ms: default_api_minimal_runtime_cache_ttl_ms(),
+            runtime_edge_enabled: default_api_runtime_edge_enabled(),
+            runtime_edge_cache_ttl_ms: default_api_runtime_edge_cache_ttl_ms(),
+            runtime_edge_top_n: default_api_runtime_edge_top_n(),
+            runtime_edge_events_capacity: default_api_runtime_edge_events_capacity(),
             read_only: false,
         }
     }
@@ -874,6 +1068,10 @@ pub struct ServerConfig {
     #[serde(default)]
     pub proxy_protocol: bool,
 
+    /// Timeout in milliseconds for reading and parsing PROXY protocol headers.
+    #[serde(default = "default_proxy_protocol_header_timeout_ms")]
+    pub proxy_protocol_header_timeout_ms: u64,
+
     #[serde(default)]
     pub metrics_port: Option<u16>,
 
@@ -897,6 +1095,7 @@ impl Default for ServerConfig {
             listen_unix_sock_perm: None,
             listen_tcp: None,
             proxy_protocol: false,
+            proxy_protocol_header_timeout_ms: default_proxy_protocol_header_timeout_ms(),
             metrics_port: None,
             metrics_whitelist: default_metrics_whitelist(),
             api: ApiConfig::default(),
@@ -1045,6 +1244,12 @@ pub struct AccessConfig {
     #[serde(default)]
     pub user_max_unique_ips: HashMap<String, usize>,
 
+    #[serde(default)]
+    pub user_max_unique_ips_mode: UserMaxUniqueIpsMode,
+
+    #[serde(default = "default_user_max_unique_ips_window_secs")]
+    pub user_max_unique_ips_window_secs: u64,
+
     #[serde(default = "default_replay_check_len")]
     pub replay_check_len: usize,
 
@@ -1064,6 +1269,8 @@ impl Default for AccessConfig {
             user_expirations: HashMap::new(),
             user_data_quota: HashMap::new(),
             user_max_unique_ips: HashMap::new(),
+            user_max_unique_ips_mode: UserMaxUniqueIpsMode::default(),
+            user_max_unique_ips_window_secs: default_user_max_unique_ips_window_secs(),
             replay_check_len: default_replay_check_len(),
             replay_window_secs: default_replay_window_secs(),
             ignore_time_skew: false,

src/crypto/random.rs

@@ -21,6 +21,7 @@ struct SecureRandomInner {
     rng: StdRng,
     cipher: AesCtr,
     buffer: Vec<u8>,
+    buffer_start: usize,
 }
 
 impl Drop for SecureRandomInner {
@@ -48,6 +49,7 @@ impl SecureRandom {
                 rng,
                 cipher,
                 buffer: Vec::with_capacity(1024),
+                buffer_start: 0,
             }),
         }
     }
@@ -59,16 +61,29 @@ impl SecureRandom {
 
         let mut written = 0usize;
         while written < out.len() {
+            if inner.buffer_start >= inner.buffer.len() {
+                inner.buffer.clear();
+                inner.buffer_start = 0;
+            }
+
             if inner.buffer.is_empty() {
                 let mut chunk = vec![0u8; CHUNK_SIZE];
                 inner.rng.fill_bytes(&mut chunk);
                 inner.cipher.apply(&mut chunk);
                 inner.buffer.extend_from_slice(&chunk);
+                inner.buffer_start = 0;
             }
 
-            let take = (out.len() - written).min(inner.buffer.len());
-            out[written..written + take].copy_from_slice(&inner.buffer[..take]);
-            inner.buffer.drain(..take);
+            let available = inner.buffer.len().saturating_sub(inner.buffer_start);
+            let take = (out.len() - written).min(available);
+            let start = inner.buffer_start;
+            let end = start + take;
+            out[written..written + take].copy_from_slice(&inner.buffer[start..end]);
+            inner.buffer_start = end;
+            if inner.buffer_start >= inner.buffer.len() {
+                inner.buffer.clear();
+                inner.buffer_start = 0;
+            }
             written += take;
         }
     }

src/ip_tracker.rs

@@ -1,252 +1,330 @@
-// src/ip_tracker.rs
-// IP address tracking and limiting for users
+// IP address tracking and per-user unique IP limiting.
 
 #![allow(dead_code)]
 
-use std::collections::{HashMap, HashSet};
+use std::collections::HashMap;
 use std::net::IpAddr;
 use std::sync::Arc;
+use std::sync::atomic::{AtomicU64, Ordering};
+use std::time::{Duration, Instant};
+
 use tokio::sync::RwLock;
 
-/// Трекер уникальных IP-адресов для каждого пользователя MTProxy
-/// 
-/// Предоставляет thread-safe механизм для:
-/// - Отслеживания активных IP-адресов каждого пользователя
-/// - Ограничения количества уникальных IP на пользователя
-/// - Автоматической очистки при отключении клиентов
+use crate::config::UserMaxUniqueIpsMode;
+
 #[derive(Debug, Clone)]
 pub struct UserIpTracker {
-    /// Маппинг: Имя пользователя -> Множество активных IP-адресов
-    active_ips: Arc<RwLock<HashMap<String, HashSet<IpAddr>>>>,
-    
-    /// Маппинг: Имя пользователя -> Максимально разрешенное количество уникальных IP
+    active_ips: Arc<RwLock<HashMap<String, HashMap<IpAddr, usize>>>>,
+    recent_ips: Arc<RwLock<HashMap<String, HashMap<IpAddr, Instant>>>>,
     max_ips: Arc<RwLock<HashMap<String, usize>>>,
+    limit_mode: Arc<RwLock<UserMaxUniqueIpsMode>>,
+    limit_window: Arc<RwLock<Duration>>,
+    last_compact_epoch_secs: Arc<AtomicU64>,
 }
 
 impl UserIpTracker {
-    /// Создать новый пустой трекер
     pub fn new() -> Self {
         Self {
             active_ips: Arc::new(RwLock::new(HashMap::new())),
+            recent_ips: Arc::new(RwLock::new(HashMap::new())),
             max_ips: Arc::new(RwLock::new(HashMap::new())),
+            limit_mode: Arc::new(RwLock::new(UserMaxUniqueIpsMode::ActiveWindow)),
+            limit_window: Arc::new(RwLock::new(Duration::from_secs(30))),
+            last_compact_epoch_secs: Arc::new(AtomicU64::new(0)),
         }
     }
 
-    /// Установить лимит уникальных IP для конкретного пользователя
-    /// 
-    /// # Arguments
-    /// * `username` - Имя пользователя
-    /// * `max_ips` - Максимальное количество одновременно активных IP-адресов
+    fn now_epoch_secs() -> u64 {
+        std::time::SystemTime::now()
+            .duration_since(std::time::UNIX_EPOCH)
+            .unwrap_or_default()
+            .as_secs()
+    }
+
+    async fn maybe_compact_empty_users(&self) {
+        const COMPACT_INTERVAL_SECS: u64 = 60;
+        let now_epoch_secs = Self::now_epoch_secs();
+        let last_compact_epoch_secs = self.last_compact_epoch_secs.load(Ordering::Relaxed);
+        if now_epoch_secs.saturating_sub(last_compact_epoch_secs) < COMPACT_INTERVAL_SECS {
+            return;
+        }
+        if self
+            .last_compact_epoch_secs
+            .compare_exchange(
+                last_compact_epoch_secs,
+                now_epoch_secs,
+                Ordering::AcqRel,
+                Ordering::Relaxed,
+            )
+            .is_err()
+        {
+            return;
+        }
+
+        let mut active_ips = self.active_ips.write().await;
+        let mut recent_ips = self.recent_ips.write().await;
+        let mut users = Vec::<String>::with_capacity(active_ips.len().saturating_add(recent_ips.len()));
+        users.extend(active_ips.keys().cloned());
+        for user in recent_ips.keys() {
+            if !active_ips.contains_key(user) {
+                users.push(user.clone());
+            }
+        }
+
+        for user in users {
+            let active_empty = active_ips.get(&user).map(|ips| ips.is_empty()).unwrap_or(true);
+            let recent_empty = recent_ips.get(&user).map(|ips| ips.is_empty()).unwrap_or(true);
+            if active_empty && recent_empty {
+                active_ips.remove(&user);
+                recent_ips.remove(&user);
+            }
+        }
+    }
+
+    pub async fn set_limit_policy(&self, mode: UserMaxUniqueIpsMode, window_secs: u64) {
+        {
+            let mut current_mode = self.limit_mode.write().await;
+            *current_mode = mode;
+        }
+        let mut current_window = self.limit_window.write().await;
+        *current_window = Duration::from_secs(window_secs.max(1));
+    }
+
     pub async fn set_user_limit(&self, username: &str, max_ips: usize) {
         let mut limits = self.max_ips.write().await;
         limits.insert(username.to_string(), max_ips);
     }
 
-    /// Загрузить лимиты из конфигурации
-    /// 
-    /// # Arguments
-    /// * `limits` - HashMap с лимитами из config.toml
-    pub async fn load_limits(&self, limits: &HashMap<String, usize>) {
-        let mut max_ips = self.max_ips.write().await;
-        for (user, limit) in limits {
-            max_ips.insert(user.clone(), *limit);
-        }
+    pub async fn remove_user_limit(&self, username: &str) {
+        let mut limits = self.max_ips.write().await;
+        limits.remove(username);
+    }
+
+    pub async fn load_limits(&self, limits: &HashMap<String, usize>) {
+        let mut max_ips = self.max_ips.write().await;
+        max_ips.clone_from(limits);
+    }
+
+    fn prune_recent(user_recent: &mut HashMap<IpAddr, Instant>, now: Instant, window: Duration) {
+        if user_recent.is_empty() {
+            return;
+        }
+        user_recent.retain(|_, seen_at| now.duration_since(*seen_at) <= window);
     }
 
-    /// Проверить, может ли пользователь подключиться с данного IP-адреса
-    /// и добавить IP в список активных, если проверка успешна
-    /// 
-    /// # Arguments
-    /// * `username` - Имя пользователя
-    /// * `ip` - IP-адрес клиента
-    /// 
-    /// # Returns
-    /// * `Ok(())` - Подключение разрешено, IP добавлен в активные
-    /// * `Err(String)` - Подключение отклонено с описанием причины
     pub async fn check_and_add(&self, username: &str, ip: IpAddr) -> Result<(), String> {
-        // Получаем лимит для пользователя
-        let max_ips = self.max_ips.read().await;
-        let limit = match max_ips.get(username) {
-            Some(limit) => *limit,
-            None => {
-                // Если лимит не задан - разрешаем безлимитный доступ
-                drop(max_ips);
-                let mut active_ips = self.active_ips.write().await;
-                let user_ips = active_ips
-                    .entry(username.to_string())
-                    .or_insert_with(HashSet::new);
-                user_ips.insert(ip);
-                return Ok(());
-            }
+        self.maybe_compact_empty_users().await;
+        let limit = {
+            let max_ips = self.max_ips.read().await;
+            max_ips.get(username).copied()
         };
-        drop(max_ips);
+        let mode = *self.limit_mode.read().await;
+        let window = *self.limit_window.read().await;
+        let now = Instant::now();
 
-        // Проверяем и обновляем активные IP
         let mut active_ips = self.active_ips.write().await;
-        let user_ips = active_ips
+        let user_active = active_ips
             .entry(username.to_string())
-            .or_insert_with(HashSet::new);
+            .or_insert_with(HashMap::new);
 
-        // Если IP уже есть в списке - это повторное подключение, разрешаем
-        if user_ips.contains(&ip) {
+        let mut recent_ips = self.recent_ips.write().await;
+        let user_recent = recent_ips
+            .entry(username.to_string())
+            .or_insert_with(HashMap::new);
+        Self::prune_recent(user_recent, now, window);
+
+        if let Some(count) = user_active.get_mut(&ip) {
+            *count = count.saturating_add(1);
+            user_recent.insert(ip, now);
             return Ok(());
         }
 
-        // Проверяем, не превышен ли лимит
-        if user_ips.len() >= limit {
-            return Err(format!(
-                "IP limit reached for user '{}': {}/{} unique IPs already connected",
-                username,
-                user_ips.len(),
-                limit
-            ));
+        if let Some(limit) = limit {
+            let active_limit_reached = user_active.len() >= limit;
+            let recent_limit_reached = user_recent.len() >= limit;
+            let deny = match mode {
+                UserMaxUniqueIpsMode::ActiveWindow => active_limit_reached,
+                UserMaxUniqueIpsMode::TimeWindow => recent_limit_reached,
+                UserMaxUniqueIpsMode::Combined => active_limit_reached || recent_limit_reached,
+            };
+
+            if deny {
+                return Err(format!(
+                    "IP limit reached for user '{}': active={}/{} recent={}/{} mode={:?}",
+                    username,
+                    user_active.len(),
+                    limit,
+                    user_recent.len(),
+                    limit,
+                    mode
+                ));
+            }
         }
 
-        // Лимит не превышен - добавляем новый IP
-        user_ips.insert(ip);
+        user_active.insert(ip, 1);
+        user_recent.insert(ip, now);
         Ok(())
     }
 
-    /// Удалить IP-адрес из списка активных при отключении клиента
-    /// 
-    /// # Arguments
-    /// * `username` - Имя пользователя
-    /// * `ip` - IP-адрес отключившегося клиента
     pub async fn remove_ip(&self, username: &str, ip: IpAddr) {
+        self.maybe_compact_empty_users().await;
         let mut active_ips = self.active_ips.write().await;
-        
         if let Some(user_ips) = active_ips.get_mut(username) {
-            user_ips.remove(&ip);
-            
-            // Если у пользователя не осталось активных IP - удаляем запись
-            // для экономии памяти
+            if let Some(count) = user_ips.get_mut(&ip) {
+                if *count > 1 {
+                    *count -= 1;
+                } else {
+                    user_ips.remove(&ip);
+                }
+            }
             if user_ips.is_empty() {
                 active_ips.remove(username);
             }
         }
     }
 
-    /// Получить текущее количество активных IP-адресов для пользователя
-    /// 
-    /// # Arguments
-    /// * `username` - Имя пользователя
-    /// 
-    /// # Returns
-    /// Количество уникальных активных IP-адресов
-    pub async fn get_active_ip_count(&self, username: &str) -> usize {
-        let active_ips = self.active_ips.read().await;
-        active_ips
-            .get(username)
-            .map(|ips| ips.len())
-            .unwrap_or(0)
+    pub async fn get_recent_counts_for_users(&self, users: &[String]) -> HashMap<String, usize> {
+        let window = *self.limit_window.read().await;
+        let now = Instant::now();
+        let recent_ips = self.recent_ips.read().await;
+
+        let mut counts = HashMap::with_capacity(users.len());
+        for user in users {
+            let count = if let Some(user_recent) = recent_ips.get(user) {
+                user_recent
+                    .values()
+                    .filter(|seen_at| now.duration_since(**seen_at) <= window)
+                    .count()
+            } else {
+                0
+            };
+            counts.insert(user.clone(), count);
+        }
+        counts
+    }
+
+    pub async fn get_active_ips_for_users(&self, users: &[String]) -> HashMap<String, Vec<IpAddr>> {
+        let active_ips = self.active_ips.read().await;
+        let mut out = HashMap::with_capacity(users.len());
+        for user in users {
+            let mut ips = active_ips
+                .get(user)
+                .map(|per_ip| per_ip.keys().copied().collect::<Vec<_>>())
+                .unwrap_or_else(Vec::new);
+            ips.sort();
+            out.insert(user.clone(), ips);
+        }
+        out
+    }
+
+    pub async fn get_recent_ips_for_users(&self, users: &[String]) -> HashMap<String, Vec<IpAddr>> {
+        let window = *self.limit_window.read().await;
+        let now = Instant::now();
+        let recent_ips = self.recent_ips.read().await;
+
+        let mut out = HashMap::with_capacity(users.len());
+        for user in users {
+            let mut ips = if let Some(user_recent) = recent_ips.get(user) {
+                user_recent
+                    .iter()
+                    .filter(|(_, seen_at)| now.duration_since(**seen_at) <= window)
+                    .map(|(ip, _)| *ip)
+                    .collect::<Vec<_>>()
+            } else {
+                Vec::new()
+            };
+            ips.sort();
+            out.insert(user.clone(), ips);
+        }
+        out
+    }
+
+    pub async fn get_active_ip_count(&self, username: &str) -> usize {
+        let active_ips = self.active_ips.read().await;
+        active_ips.get(username).map(|ips| ips.len()).unwrap_or(0)
     }
 
-    /// Получить список всех активных IP-адресов для пользователя
-    /// 
-    /// # Arguments
-    /// * `username` - Имя пользователя
-    /// 
-    /// # Returns
-    /// Вектор с активными IP-адресами
     pub async fn get_active_ips(&self, username: &str) -> Vec<IpAddr> {
         let active_ips = self.active_ips.read().await;
         active_ips
             .get(username)
-            .map(|ips| ips.iter().copied().collect())
+            .map(|ips| ips.keys().copied().collect())
             .unwrap_or_else(Vec::new)
     }
 
-    /// Получить статистику по всем пользователям
-    /// 
-    /// # Returns
-    /// Вектор кортежей: (имя_пользователя, количество_активных_IP, лимит)
     pub async fn get_stats(&self) -> Vec<(String, usize, usize)> {
         let active_ips = self.active_ips.read().await;
         let max_ips = self.max_ips.read().await;
 
         let mut stats = Vec::new();
-        
-        // Собираем статистику по пользователям с активными подключениями
         for (username, user_ips) in active_ips.iter() {
             let limit = max_ips.get(username).copied().unwrap_or(0);
             stats.push((username.clone(), user_ips.len(), limit));
         }
-        
-        stats.sort_by(|a, b| a.0.cmp(&b.0)); // Сортируем по имени пользователя
+
+        stats.sort_by(|a, b| a.0.cmp(&b.0));
         stats
     }
 
-    /// Очистить все активные IP для пользователя (при необходимости)
-    /// 
-    /// # Arguments
-    /// * `username` - Имя пользователя
     pub async fn clear_user_ips(&self, username: &str) {
         let mut active_ips = self.active_ips.write().await;
         active_ips.remove(username);
+        drop(active_ips);
+
+        let mut recent_ips = self.recent_ips.write().await;
+        recent_ips.remove(username);
     }
 
-    /// Очистить всю статистику (использовать с осторожностью!)
     pub async fn clear_all(&self) {
         let mut active_ips = self.active_ips.write().await;
         active_ips.clear();
+        drop(active_ips);
+
+        let mut recent_ips = self.recent_ips.write().await;
+        recent_ips.clear();
     }
 
-    /// Проверить, подключен ли пользователь с данного IP
-    /// 
-    /// # Arguments
-    /// * `username` - Имя пользователя
-    /// * `ip` - IP-адрес для проверки
-    /// 
-    /// # Returns
-    /// `true` если IP активен, `false` если нет
     pub async fn is_ip_active(&self, username: &str, ip: IpAddr) -> bool {
         let active_ips = self.active_ips.read().await;
         active_ips
             .get(username)
-            .map(|ips| ips.contains(&ip))
+            .map(|ips| ips.contains_key(&ip))
             .unwrap_or(false)
     }
 
-    /// Получить лимит для пользователя
-    /// 
-    /// # Arguments
-    /// * `username` - Имя пользователя
-    /// 
-    /// # Returns
-    /// Лимит IP-адресов или None, если лимит не установлен
     pub async fn get_user_limit(&self, username: &str) -> Option<usize> {
         let max_ips = self.max_ips.read().await;
         max_ips.get(username).copied()
     }
 
-    /// Форматировать статистику в читаемый текст
-    /// 
-    /// # Returns
-    /// Строка со статистикой для логов или мониторинга
     pub async fn format_stats(&self) -> String {
         let stats = self.get_stats().await;
-        
+
         if stats.is_empty() {
             return String::from("No active users");
         }
-        
+
         let mut output = String::from("User IP Statistics:\n");
         output.push_str("==================\n");
-        
+
         for (username, active_count, limit) in stats {
             output.push_str(&format!(
                 "User: {:<20} Active IPs: {}/{}\n",
                 username,
                 active_count,
-                if limit > 0 { limit.to_string() } else { "unlimited".to_string() }
+                if limit > 0 {
+                    limit.to_string()
+                } else {
+                    "unlimited".to_string()
+                }
             ));
-            
+
             let ips = self.get_active_ips(&username).await;
             for ip in ips {
-                output.push_str(&format!("  └─ {}\n", ip));
+                output.push_str(&format!("  - {}\n", ip));
             }
         }
-        
+
         output
     }
 }
@@ -257,10 +335,6 @@ impl Default for UserIpTracker {
     }
 }
 
-// ============================================================================
-// ТЕСТЫ
-// ============================================================================
-
 #[cfg(test)]
 mod tests {
     use super::*;
@@ -283,17 +357,33 @@ mod tests {
         let ip2 = test_ipv4(192, 168, 1, 2);
         let ip3 = test_ipv4(192, 168, 1, 3);
 
-        // Первые два IP должны быть приняты
         assert!(tracker.check_and_add("test_user", ip1).await.is_ok());
         assert!(tracker.check_and_add("test_user", ip2).await.is_ok());
-
-        // Третий IP должен быть отклонен
         assert!(tracker.check_and_add("test_user", ip3).await.is_err());
 
-        // Проверяем счетчик
         assert_eq!(tracker.get_active_ip_count("test_user").await, 2);
     }
 
+    #[tokio::test]
+    async fn test_active_window_rejects_new_ip_and_keeps_existing_session() {
+        let tracker = UserIpTracker::new();
+        tracker.set_user_limit("test_user", 1).await;
+        tracker
+            .set_limit_policy(UserMaxUniqueIpsMode::ActiveWindow, 30)
+            .await;
+
+        let ip1 = test_ipv4(10, 10, 10, 1);
+        let ip2 = test_ipv4(10, 10, 10, 2);
+
+        assert!(tracker.check_and_add("test_user", ip1).await.is_ok());
+        assert!(tracker.is_ip_active("test_user", ip1).await);
+        assert!(tracker.check_and_add("test_user", ip2).await.is_err());
+
+        // Existing session remains active; only new unique IP is denied.
+        assert!(tracker.is_ip_active("test_user", ip1).await);
+        assert_eq!(tracker.get_active_ip_count("test_user").await, 1);
+    }
+
     #[tokio::test]
     async fn test_reconnection_from_same_ip() {
         let tracker = UserIpTracker::new();
@@ -301,16 +391,29 @@ mod tests {
 
         let ip1 = test_ipv4(192, 168, 1, 1);
 
-        // Первое подключение
         assert!(tracker.check_and_add("test_user", ip1).await.is_ok());
-        
-        // Повторное подключение с того же IP должно пройти
         assert!(tracker.check_and_add("test_user", ip1).await.is_ok());
-        
-        // Счетчик не должен увеличиться
         assert_eq!(tracker.get_active_ip_count("test_user").await, 1);
     }
 
+    #[tokio::test]
+    async fn test_same_ip_disconnect_keeps_active_while_other_session_alive() {
+        let tracker = UserIpTracker::new();
+        tracker.set_user_limit("test_user", 2).await;
+
+        let ip1 = test_ipv4(192, 168, 1, 1);
+
+        assert!(tracker.check_and_add("test_user", ip1).await.is_ok());
+        assert!(tracker.check_and_add("test_user", ip1).await.is_ok());
+        assert_eq!(tracker.get_active_ip_count("test_user").await, 1);
+
+        tracker.remove_ip("test_user", ip1).await;
+        assert_eq!(tracker.get_active_ip_count("test_user").await, 1);
+
+        tracker.remove_ip("test_user", ip1).await;
+        assert_eq!(tracker.get_active_ip_count("test_user").await, 0);
+    }
+
     #[tokio::test]
     async fn test_ip_removal() {
         let tracker = UserIpTracker::new();
@@ -320,36 +423,28 @@ mod tests {
         let ip2 = test_ipv4(192, 168, 1, 2);
         let ip3 = test_ipv4(192, 168, 1, 3);
 
-        // Добавляем два IP
         assert!(tracker.check_and_add("test_user", ip1).await.is_ok());
         assert!(tracker.check_and_add("test_user", ip2).await.is_ok());
-        
-        // Третий не должен пройти
         assert!(tracker.check_and_add("test_user", ip3).await.is_err());
 
-        // Удаляем первый IP
         tracker.remove_ip("test_user", ip1).await;
-        
-        // Теперь третий должен пройти
+
         assert!(tracker.check_and_add("test_user", ip3).await.is_ok());
-        
         assert_eq!(tracker.get_active_ip_count("test_user").await, 2);
     }
 
     #[tokio::test]
     async fn test_no_limit() {
         let tracker = UserIpTracker::new();
-        // Не устанавливаем лимит для test_user
 
         let ip1 = test_ipv4(192, 168, 1, 1);
         let ip2 = test_ipv4(192, 168, 1, 2);
         let ip3 = test_ipv4(192, 168, 1, 3);
 
-        // Без лимита все IP должны проходить
         assert!(tracker.check_and_add("test_user", ip1).await.is_ok());
         assert!(tracker.check_and_add("test_user", ip2).await.is_ok());
         assert!(tracker.check_and_add("test_user", ip3).await.is_ok());
-        
+
         assert_eq!(tracker.get_active_ip_count("test_user").await, 3);
     }
 
@@ -362,11 +457,9 @@ mod tests {
         let ip1 = test_ipv4(192, 168, 1, 1);
         let ip2 = test_ipv4(192, 168, 1, 2);
 
-        // user1 может использовать 2 IP
         assert!(tracker.check_and_add("user1", ip1).await.is_ok());
         assert!(tracker.check_and_add("user1", ip2).await.is_ok());
 
-        // user2 может использовать только 1 IP
         assert!(tracker.check_and_add("user2", ip1).await.is_ok());
         assert!(tracker.check_and_add("user2", ip2).await.is_err());
     }
@@ -379,10 +472,9 @@ mod tests {
         let ipv4 = test_ipv4(192, 168, 1, 1);
         let ipv6 = test_ipv6();
 
-        // Должны работать оба типа адресов
         assert!(tracker.check_and_add("test_user", ipv4).await.is_ok());
         assert!(tracker.check_and_add("test_user", ipv6).await.is_ok());
-        
+
         assert_eq!(tracker.get_active_ip_count("test_user").await, 2);
     }
 
@@ -417,8 +509,7 @@ mod tests {
 
         let stats = tracker.get_stats().await;
         assert_eq!(stats.len(), 2);
-        
-        // Проверяем наличие обоих пользователей в статистике
+
         assert!(stats.iter().any(|(name, _, _)| name == "user1"));
         assert!(stats.iter().any(|(name, _, _)| name == "user2"));
     }
@@ -427,10 +518,10 @@ mod tests {
     async fn test_clear_user_ips() {
         let tracker = UserIpTracker::new();
         let ip1 = test_ipv4(192, 168, 1, 1);
-        
+
         tracker.check_and_add("test_user", ip1).await.unwrap();
         assert_eq!(tracker.get_active_ip_count("test_user").await, 1);
-        
+
         tracker.clear_user_ips("test_user").await;
         assert_eq!(tracker.get_active_ip_count("test_user").await, 0);
     }
@@ -440,9 +531,9 @@ mod tests {
         let tracker = UserIpTracker::new();
         let ip1 = test_ipv4(192, 168, 1, 1);
         let ip2 = test_ipv4(192, 168, 1, 2);
-        
+
         tracker.check_and_add("test_user", ip1).await.unwrap();
-        
+
         assert!(tracker.is_ip_active("test_user", ip1).await);
         assert!(!tracker.is_ip_active("test_user", ip2).await);
     }
@@ -450,15 +541,85 @@ mod tests {
     #[tokio::test]
     async fn test_load_limits_from_config() {
         let tracker = UserIpTracker::new();
-        
+
         let mut config_limits = HashMap::new();
         config_limits.insert("user1".to_string(), 5);
         config_limits.insert("user2".to_string(), 3);
-        
+
         tracker.load_limits(&config_limits).await;
-        
+
         assert_eq!(tracker.get_user_limit("user1").await, Some(5));
         assert_eq!(tracker.get_user_limit("user2").await, Some(3));
         assert_eq!(tracker.get_user_limit("user3").await, None);
     }
+
+    #[tokio::test]
+    async fn test_load_limits_replaces_previous_map() {
+        let tracker = UserIpTracker::new();
+
+        let mut first = HashMap::new();
+        first.insert("user1".to_string(), 2);
+        first.insert("user2".to_string(), 3);
+        tracker.load_limits(&first).await;
+
+        let mut second = HashMap::new();
+        second.insert("user2".to_string(), 5);
+        tracker.load_limits(&second).await;
+
+        assert_eq!(tracker.get_user_limit("user1").await, None);
+        assert_eq!(tracker.get_user_limit("user2").await, Some(5));
+    }
+
+    #[tokio::test]
+    async fn test_time_window_mode_blocks_recent_ip_churn() {
+        let tracker = UserIpTracker::new();
+        tracker.set_user_limit("test_user", 1).await;
+        tracker
+            .set_limit_policy(UserMaxUniqueIpsMode::TimeWindow, 30)
+            .await;
+
+        let ip1 = test_ipv4(10, 0, 0, 1);
+        let ip2 = test_ipv4(10, 0, 0, 2);
+
+        assert!(tracker.check_and_add("test_user", ip1).await.is_ok());
+        tracker.remove_ip("test_user", ip1).await;
+        assert!(tracker.check_and_add("test_user", ip2).await.is_err());
+    }
+
+    #[tokio::test]
+    async fn test_combined_mode_enforces_active_and_recent_limits() {
+        let tracker = UserIpTracker::new();
+        tracker.set_user_limit("test_user", 1).await;
+        tracker
+            .set_limit_policy(UserMaxUniqueIpsMode::Combined, 30)
+            .await;
+
+        let ip1 = test_ipv4(10, 0, 1, 1);
+        let ip2 = test_ipv4(10, 0, 1, 2);
+
+        assert!(tracker.check_and_add("test_user", ip1).await.is_ok());
+        assert!(tracker.check_and_add("test_user", ip2).await.is_err());
+
+        tracker.remove_ip("test_user", ip1).await;
+        assert!(tracker.check_and_add("test_user", ip2).await.is_err());
+    }
+
+    #[tokio::test]
+    async fn test_time_window_expires() {
+        let tracker = UserIpTracker::new();
+        tracker.set_user_limit("test_user", 1).await;
+        tracker
+            .set_limit_policy(UserMaxUniqueIpsMode::TimeWindow, 1)
+            .await;
+
+        let ip1 = test_ipv4(10, 1, 0, 1);
+        let ip2 = test_ipv4(10, 1, 0, 2);
+
+        assert!(tracker.check_and_add("test_user", ip1).await.is_ok());
+        tracker.remove_ip("test_user", ip1).await;
+        assert!(tracker.check_and_add("test_user", ip2).await.is_err());
+
+        tokio::time::sleep(Duration::from_millis(1100)).await;
+        assert!(tracker.check_and_add("test_user", ip2).await.is_ok());
+    }
 }

src/metrics.rs

@@ -968,6 +968,229 @@ async fn render_metrics(stats: &Stats, config: &ProxyConfig, ip_tracker: &UserIp
             0
         }
     );
+    let _ = writeln!(
+        out,
+        "# HELP telemt_me_adaptive_floor_cpu_cores_detected Runtime detected logical CPU cores for adaptive floor"
+    );
+    let _ = writeln!(
+        out,
+        "# TYPE telemt_me_adaptive_floor_cpu_cores_detected gauge"
+    );
+    let _ = writeln!(
+        out,
+        "telemt_me_adaptive_floor_cpu_cores_detected {}",
+        if me_allows_normal {
+            stats.get_me_floor_cpu_cores_detected_gauge()
+        } else {
+            0
+        }
+    );
+    let _ = writeln!(
+        out,
+        "# HELP telemt_me_adaptive_floor_cpu_cores_effective Runtime effective logical CPU cores for adaptive floor"
+    );
+    let _ = writeln!(
+        out,
+        "# TYPE telemt_me_adaptive_floor_cpu_cores_effective gauge"
+    );
+    let _ = writeln!(
+        out,
+        "telemt_me_adaptive_floor_cpu_cores_effective {}",
+        if me_allows_normal {
+            stats.get_me_floor_cpu_cores_effective_gauge()
+        } else {
+            0
+        }
+    );
+    let _ = writeln!(
+        out,
+        "# HELP telemt_me_adaptive_floor_global_cap_raw Runtime raw global adaptive floor cap"
+    );
+    let _ = writeln!(
+        out,
+        "# TYPE telemt_me_adaptive_floor_global_cap_raw gauge"
+    );
+    let _ = writeln!(
+        out,
+        "telemt_me_adaptive_floor_global_cap_raw {}",
+        if me_allows_normal {
+            stats.get_me_floor_global_cap_raw_gauge()
+        } else {
+            0
+        }
+    );
+    let _ = writeln!(
+        out,
+        "# HELP telemt_me_adaptive_floor_global_cap_effective Runtime effective global adaptive floor cap"
+    );
+    let _ = writeln!(
+        out,
+        "# TYPE telemt_me_adaptive_floor_global_cap_effective gauge"
+    );
+    let _ = writeln!(
+        out,
+        "telemt_me_adaptive_floor_global_cap_effective {}",
+        if me_allows_normal {
+            stats.get_me_floor_global_cap_effective_gauge()
+        } else {
+            0
+        }
+    );
+    let _ = writeln!(
+        out,
+        "# HELP telemt_me_adaptive_floor_target_writers_total Runtime adaptive floor target writers total"
+    );
+    let _ = writeln!(
+        out,
+        "# TYPE telemt_me_adaptive_floor_target_writers_total gauge"
+    );
+    let _ = writeln!(
+        out,
+        "telemt_me_adaptive_floor_target_writers_total {}",
+        if me_allows_normal {
+            stats.get_me_floor_target_writers_total_gauge()
+        } else {
+            0
+        }
+    );
+    let _ = writeln!(
+        out,
+        "# HELP telemt_me_adaptive_floor_active_cap_configured Runtime configured active writer cap"
+    );
+    let _ = writeln!(
+        out,
+        "# TYPE telemt_me_adaptive_floor_active_cap_configured gauge"
+    );
+    let _ = writeln!(
+        out,
+        "telemt_me_adaptive_floor_active_cap_configured {}",
+        if me_allows_normal {
+            stats.get_me_floor_active_cap_configured_gauge()
+        } else {
+            0
+        }
+    );
+    let _ = writeln!(
+        out,
+        "# HELP telemt_me_adaptive_floor_active_cap_effective Runtime effective active writer cap"
+    );
+    let _ = writeln!(
+        out,
+        "# TYPE telemt_me_adaptive_floor_active_cap_effective gauge"
+    );
+    let _ = writeln!(
+        out,
+        "telemt_me_adaptive_floor_active_cap_effective {}",
+        if me_allows_normal {
+            stats.get_me_floor_active_cap_effective_gauge()
+        } else {
+            0
+        }
+    );
+    let _ = writeln!(
+        out,
+        "# HELP telemt_me_adaptive_floor_warm_cap_configured Runtime configured warm writer cap"
+    );
+    let _ = writeln!(
+        out,
+        "# TYPE telemt_me_adaptive_floor_warm_cap_configured gauge"
+    );
+    let _ = writeln!(
+        out,
+        "telemt_me_adaptive_floor_warm_cap_configured {}",
+        if me_allows_normal {
+            stats.get_me_floor_warm_cap_configured_gauge()
+        } else {
+            0
+        }
+    );
+    let _ = writeln!(
+        out,
+        "# HELP telemt_me_adaptive_floor_warm_cap_effective Runtime effective warm writer cap"
+    );
+    let _ = writeln!(
+        out,
+        "# TYPE telemt_me_adaptive_floor_warm_cap_effective gauge"
+    );
+    let _ = writeln!(
+        out,
+        "telemt_me_adaptive_floor_warm_cap_effective {}",
+        if me_allows_normal {
+            stats.get_me_floor_warm_cap_effective_gauge()
+        } else {
+            0
+        }
+    );
+    let _ = writeln!(
+        out,
+        "# HELP telemt_me_writers_active_current Current non-draining active ME writers"
+    );
+    let _ = writeln!(out, "# TYPE telemt_me_writers_active_current gauge");
+    let _ = writeln!(
+        out,
+        "telemt_me_writers_active_current {}",
+        if me_allows_normal {
+            stats.get_me_writers_active_current_gauge()
+        } else {
+            0
+        }
+    );
+    let _ = writeln!(
+        out,
+        "# HELP telemt_me_writers_warm_current Current non-draining warm ME writers"
+    );
+    let _ = writeln!(out, "# TYPE telemt_me_writers_warm_current gauge");
+    let _ = writeln!(
+        out,
+        "telemt_me_writers_warm_current {}",
+        if me_allows_normal {
+            stats.get_me_writers_warm_current_gauge()
+        } else {
+            0
+        }
+    );
+    let _ = writeln!(
+        out,
+        "# HELP telemt_me_floor_cap_block_total Reconnect attempts blocked by adaptive floor caps"
+    );
+    let _ = writeln!(out, "# TYPE telemt_me_floor_cap_block_total counter");
+    let _ = writeln!(
+        out,
+        "telemt_me_floor_cap_block_total {}",
+        if me_allows_normal {
+            stats.get_me_floor_cap_block_total()
+        } else {
+            0
+        }
+    );
+    let _ = writeln!(
+        out,
+        "# HELP telemt_me_floor_swap_idle_total Adaptive floor cap recovery via idle writer swap"
+    );
+    let _ = writeln!(out, "# TYPE telemt_me_floor_swap_idle_total counter");
+    let _ = writeln!(
+        out,
+        "telemt_me_floor_swap_idle_total {}",
+        if me_allows_normal {
+            stats.get_me_floor_swap_idle_total()
+        } else {
+            0
+        }
+    );
+    let _ = writeln!(
+        out,
+        "# HELP telemt_me_floor_swap_idle_failed_total Failed idle swap attempts under adaptive floor caps"
+    );
+    let _ = writeln!(out, "# TYPE telemt_me_floor_swap_idle_failed_total counter");
+    let _ = writeln!(
+        out,
+        "telemt_me_floor_swap_idle_failed_total {}",
+        if me_allows_normal {
+            stats.get_me_floor_swap_idle_failed_total()
+        } else {
+            0
+        }
+    );
 
     let _ = writeln!(out, "# HELP telemt_secure_padding_invalid_total Invalid secure frame lengths");
     let _ = writeln!(out, "# TYPE telemt_secure_padding_invalid_total counter");
@@ -1199,6 +1422,48 @@ async fn render_metrics(stats: &Stats, config: &ProxyConfig, ip_tracker: &UserIp
             0
         }
     );
+    let _ = writeln!(
+        out,
+        "# HELP telemt_me_no_writer_failfast_total ME route failfast errors due to missing writer in bounded wait window"
+    );
+    let _ = writeln!(out, "# TYPE telemt_me_no_writer_failfast_total counter");
+    let _ = writeln!(
+        out,
+        "telemt_me_no_writer_failfast_total {}",
+        if me_allows_normal {
+            stats.get_me_no_writer_failfast_total()
+        } else {
+            0
+        }
+    );
+    let _ = writeln!(
+        out,
+        "# HELP telemt_me_async_recovery_trigger_total Async ME recovery trigger attempts from route path"
+    );
+    let _ = writeln!(out, "# TYPE telemt_me_async_recovery_trigger_total counter");
+    let _ = writeln!(
+        out,
+        "telemt_me_async_recovery_trigger_total {}",
+        if me_allows_normal {
+            stats.get_me_async_recovery_trigger_total()
+        } else {
+            0
+        }
+    );
+    let _ = writeln!(
+        out,
+        "# HELP telemt_me_inline_recovery_total Legacy inline ME recovery attempts from route path"
+    );
+    let _ = writeln!(out, "# TYPE telemt_me_inline_recovery_total counter");
+    let _ = writeln!(
+        out,
+        "telemt_me_inline_recovery_total {}",
+        if me_allows_normal {
+            stats.get_me_inline_recovery_total()
+        } else {
+            0
+        }
+    );
 
     let unresolved_writer_losses = if me_allows_normal {
         stats
@@ -1237,6 +1502,29 @@ async fn render_metrics(stats: &Stats, config: &ProxyConfig, ip_tracker: &UserIp
     let _ = writeln!(out, "# TYPE telemt_user_msgs_from_client counter");
     let _ = writeln!(out, "# HELP telemt_user_msgs_to_client Per-user messages sent");
     let _ = writeln!(out, "# TYPE telemt_user_msgs_to_client counter");
+    let _ = writeln!(
+        out,
+        "# HELP telemt_ip_reservation_rollback_total IP reservation rollbacks caused by later limit checks"
+    );
+    let _ = writeln!(out, "# TYPE telemt_ip_reservation_rollback_total counter");
+    let _ = writeln!(
+        out,
+        "telemt_ip_reservation_rollback_total{{reason=\"tcp_limit\"}} {}",
+        if core_enabled {
+            stats.get_ip_reservation_rollback_tcp_limit_total()
+        } else {
+            0
+        }
+    );
+    let _ = writeln!(
+        out,
+        "telemt_ip_reservation_rollback_total{{reason=\"quota_limit\"}} {}",
+        if core_enabled {
+            stats.get_ip_reservation_rollback_quota_limit_total()
+        } else {
+            0
+        }
+    );
     let _ = writeln!(
         out,
         "# HELP telemt_telemetry_user_series_suppressed User-labeled metric series suppression flag"
@@ -1267,11 +1555,21 @@ async fn render_metrics(stats: &Stats, config: &ProxyConfig, ip_tracker: &UserIp
             .collect();
 
         let mut unique_users = BTreeSet::new();
+        unique_users.extend(config.access.users.keys().cloned());
         unique_users.extend(config.access.user_max_unique_ips.keys().cloned());
         unique_users.extend(ip_counts.keys().cloned());
+        let unique_users_vec: Vec<String> = unique_users.iter().cloned().collect();
+        let recent_counts = ip_tracker
+            .get_recent_counts_for_users(&unique_users_vec)
+            .await;
 
         let _ = writeln!(out, "# HELP telemt_user_unique_ips_current Per-user current number of unique active IPs");
         let _ = writeln!(out, "# TYPE telemt_user_unique_ips_current gauge");
+        let _ = writeln!(
+            out,
+            "# HELP telemt_user_unique_ips_recent_window Per-user unique IPs seen in configured observation window"
+        );
+        let _ = writeln!(out, "# TYPE telemt_user_unique_ips_recent_window gauge");
         let _ = writeln!(out, "# HELP telemt_user_unique_ips_limit Per-user configured unique IP limit (0 means unlimited)");
         let _ = writeln!(out, "# TYPE telemt_user_unique_ips_limit gauge");
         let _ = writeln!(out, "# HELP telemt_user_unique_ips_utilization Per-user unique IP usage ratio (0 for unlimited)");
@@ -1286,6 +1584,12 @@ async fn render_metrics(stats: &Stats, config: &ProxyConfig, ip_tracker: &UserIp
                 0.0
             };
             let _ = writeln!(out, "telemt_user_unique_ips_current{{user=\"{}\"}} {}", user, current);
+            let _ = writeln!(
+                out,
+                "telemt_user_unique_ips_recent_window{{user=\"{}\"}} {}",
+                user,
+                recent_counts.get(&user).copied().unwrap_or(0)
+            );
             let _ = writeln!(out, "telemt_user_unique_ips_limit{{user=\"{}\"}} {}", user, limit);
             let _ = writeln!(
                 out,
@@ -1378,6 +1682,7 @@ mod tests {
         assert!(output.contains("telemt_user_msgs_from_client{user=\"alice\"} 1"));
         assert!(output.contains("telemt_user_msgs_to_client{user=\"alice\"} 2"));
         assert!(output.contains("telemt_user_unique_ips_current{user=\"alice\"} 1"));
+        assert!(output.contains("telemt_user_unique_ips_recent_window{user=\"alice\"} 1"));
         assert!(output.contains("telemt_user_unique_ips_limit{user=\"alice\"} 4"));
         assert!(output.contains("telemt_user_unique_ips_utilization{user=\"alice\"} 0.250000"));
     }
@@ -1391,7 +1696,8 @@ mod tests {
         assert!(output.contains("telemt_connections_total 0"));
         assert!(output.contains("telemt_connections_bad_total 0"));
         assert!(output.contains("telemt_handshake_timeouts_total 0"));
-        assert!(!output.contains("user="));
+        assert!(output.contains("telemt_user_unique_ips_current{user="));
+        assert!(output.contains("telemt_user_unique_ips_recent_window{user="));
     }
 
     #[tokio::test]
@@ -1412,6 +1718,7 @@ mod tests {
             "# TYPE telemt_me_writer_removed_unexpected_minus_restored_total gauge"
         ));
         assert!(output.contains("# TYPE telemt_user_unique_ips_current gauge"));
+        assert!(output.contains("# TYPE telemt_user_unique_ips_recent_window gauge"));
         assert!(output.contains("# TYPE telemt_user_unique_ips_limit gauge"));
         assert!(output.contains("# TYPE telemt_user_unique_ips_utilization gauge"));
     }

src/proxy/client.rs

@@ -97,8 +97,11 @@ where
         .unwrap_or_else(|_| "0.0.0.0:443".parse().unwrap());
 
     if proxy_protocol_enabled {
-        match parse_proxy_protocol(&mut stream, peer).await {
-            Ok(info) => {
+        let proxy_header_timeout = Duration::from_millis(
+            config.server.proxy_protocol_header_timeout_ms.max(1),
+        );
+        match timeout(proxy_header_timeout, parse_proxy_protocol(&mut stream, peer)).await {
+            Ok(Ok(info)) => {
                 debug!(
                     peer = %peer,
                     client = %info.src_addr,
@@ -110,12 +113,18 @@ where
                     local_addr = dst;
                 }
             }
-            Err(e) => {
+            Ok(Err(e)) => {
                 stats.increment_connects_bad();
                 warn!(peer = %peer, error = %e, "Invalid PROXY protocol header");
                 record_beobachten_class(&beobachten, &config, peer.ip(), "other");
                 return Err(e);
             }
+            Err(_) => {
+                stats.increment_connects_bad();
+                warn!(peer = %peer, timeout_ms = proxy_header_timeout.as_millis(), "PROXY protocol header timeout");
+                record_beobachten_class(&beobachten, &config, peer.ip(), "other");
+                return Err(ProxyError::InvalidProxyProtocol);
+            }
         }
     }
 
@@ -161,7 +170,7 @@ where
 
             let (read_half, write_half) = tokio::io::split(stream);
 
-            let (mut tls_reader, tls_writer, _tls_user) = match handle_tls_handshake(
+            let (mut tls_reader, tls_writer, tls_user) = match handle_tls_handshake(
                 &handshake, read_half, write_half, real_peer,
                 &config, &replay_checker, &rng, tls_cache.clone(),
             ).await {
@@ -190,7 +199,7 @@ where
 
             let (crypto_reader, crypto_writer, success) = match handle_mtproto_handshake(
                 &mtproto_handshake, tls_reader, tls_writer, real_peer,
-                &config, &replay_checker, true,
+                &config, &replay_checker, true, Some(tls_user.as_str()),
             ).await {
                 HandshakeResult::Success(result) => result,
                 HandshakeResult::BadClient { reader: _, writer: _ } => {
@@ -234,7 +243,7 @@ where
 
             let (crypto_reader, crypto_writer, success) = match handle_mtproto_handshake(
                 &handshake, read_half, write_half, real_peer,
-                &config, &replay_checker, false,
+                &config, &replay_checker, false, None,
             ).await {
                 HandshakeResult::Success(result) => result,
                 HandshakeResult::BadClient { reader, writer } => {
@@ -415,8 +424,16 @@ impl RunningClientHandler {
         let mut local_addr = self.stream.local_addr().map_err(ProxyError::Io)?;
 
         if self.proxy_protocol_enabled {
-            match parse_proxy_protocol(&mut self.stream, self.peer).await {
-                Ok(info) => {
+            let proxy_header_timeout = Duration::from_millis(
+                self.config.server.proxy_protocol_header_timeout_ms.max(1),
+            );
+            match timeout(
+                proxy_header_timeout,
+                parse_proxy_protocol(&mut self.stream, self.peer),
+            )
+            .await
+            {
+                Ok(Ok(info)) => {
                     debug!(
                         peer = %self.peer,
                         client = %info.src_addr,
@@ -428,7 +445,7 @@ impl RunningClientHandler {
                         local_addr = dst;
                     }
                 }
-                Err(e) => {
+                Ok(Err(e)) => {
                     self.stats.increment_connects_bad();
                     warn!(peer = %self.peer, error = %e, "Invalid PROXY protocol header");
                     record_beobachten_class(
@@ -439,6 +456,21 @@ impl RunningClientHandler {
                     );
                     return Err(e);
                 }
+                Err(_) => {
+                    self.stats.increment_connects_bad();
+                    warn!(
+                        peer = %self.peer,
+                        timeout_ms = proxy_header_timeout.as_millis(),
+                        "PROXY protocol header timeout"
+                    );
+                    record_beobachten_class(
+                        &self.beobachten,
+                        &self.config,
+                        self.peer.ip(),
+                        "other",
+                    );
+                    return Err(ProxyError::InvalidProxyProtocol);
+                }
             }
         }
 
@@ -494,7 +526,7 @@ impl RunningClientHandler {
 
         let (read_half, write_half) = self.stream.into_split();
 
-        let (mut tls_reader, tls_writer, _tls_user) = match handle_tls_handshake(
+        let (mut tls_reader, tls_writer, tls_user) = match handle_tls_handshake(
             &handshake,
             read_half,
             write_half,
@@ -538,6 +570,7 @@ impl RunningClientHandler {
             &config,
             &replay_checker,
             true,
+            Some(tls_user.as_str()),
         )
         .await
         {
@@ -611,6 +644,7 @@ impl RunningClientHandler {
             &config,
             &replay_checker,
             false,
+            None,
         )
         .await
         {
@@ -672,42 +706,16 @@ impl RunningClientHandler {
         R: AsyncRead + Unpin + Send + 'static,
         W: AsyncWrite + Unpin + Send + 'static,
     {
-        let user = &success.user;
+        let user = success.user.clone();
 
-        if let Err(e) = Self::check_user_limits_static(user, &config, &stats, peer_addr, &ip_tracker).await {
+        if let Err(e) = Self::check_user_limits_static(&user, &config, &stats, peer_addr, &ip_tracker).await {
             warn!(user = %user, error = %e, "User limit exceeded");
             return Err(e);
         }
 
-        // IP Cleanup Guard: автоматически удаляет IP при выходе из scope
-        struct IpCleanupGuard {
-            tracker: Arc<UserIpTracker>,
-            user: String,
-            ip: std::net::IpAddr,
-        }
-        
-        impl Drop for IpCleanupGuard {
-            fn drop(&mut self) {
-                let tracker = self.tracker.clone();
-                let user = self.user.clone();
-                let ip = self.ip;
-                tokio::spawn(async move {
-                    tracker.remove_ip(&user, ip).await;
-                    debug!(user = %user, ip = %ip, "IP cleaned up on disconnect");
-                });
-            }
-        }
-        
-        let _cleanup = IpCleanupGuard {
-            tracker: ip_tracker,
-            user: user.clone(),
-            ip: peer_addr.ip(),
-        };
-
-        // Decide: middle proxy or direct
-        if config.general.use_middle_proxy {
+        let relay_result = if config.general.use_middle_proxy {
             if let Some(ref pool) = me_pool {
-                return handle_via_middle_proxy(
+                handle_via_middle_proxy(
                     client_reader,
                     client_writer,
                     success,
@@ -718,23 +726,38 @@ impl RunningClientHandler {
                     local_addr,
                     rng,
                 )
-                .await;
+                .await
+            } else {
+                warn!("use_middle_proxy=true but MePool not initialized, falling back to direct");
+                handle_via_direct(
+                    client_reader,
+                    client_writer,
+                    success,
+                    upstream_manager,
+                    stats,
+                    config,
+                    buffer_pool,
+                    rng,
+                )
+                .await
             }
-            warn!("use_middle_proxy=true but MePool not initialized, falling back to direct");
-        }
+        } else {
+            // Direct mode (original behavior)
+            handle_via_direct(
+                client_reader,
+                client_writer,
+                success,
+                upstream_manager,
+                stats,
+                config,
+                buffer_pool,
+                rng,
+            )
+            .await
+        };
 
-        // Direct mode (original behavior)
-        handle_via_direct(
-            client_reader,
-            client_writer,
-            success,
-            upstream_manager,
-            stats,
-            config,
-            buffer_pool,
-            rng,
-        )
-        .await
+        ip_tracker.remove_ip(&user, peer_addr.ip()).await;
+        relay_result
     }
 
     async fn check_user_limits_static(
@@ -752,22 +775,32 @@ impl RunningClientHandler {
             });
         }
 
+        let mut ip_reserved = false;
         // IP limit check
-        if let Err(reason) = ip_tracker.check_and_add(user, peer_addr.ip()).await {
-            warn!(
-                user = %user,
-                ip = %peer_addr.ip(),
-                reason = %reason,
-                "IP limit exceeded"
-            );
-            return Err(ProxyError::ConnectionLimitExceeded {
-                user: user.to_string(),
-            });
+        match ip_tracker.check_and_add(user, peer_addr.ip()).await {
+            Ok(()) => {
+                ip_reserved = true;
+            }
+            Err(reason) => {
+                warn!(
+                    user = %user,
+                    ip = %peer_addr.ip(),
+                    reason = %reason,
+                    "IP limit exceeded"
+                );
+                return Err(ProxyError::ConnectionLimitExceeded {
+                    user: user.to_string(),
+                });
+            }
         }
 
         if let Some(limit) = config.access.user_max_tcp_conns.get(user)
             && stats.get_user_curr_connects(user) >= *limit as u64
         {
+            if ip_reserved {
+                ip_tracker.remove_ip(user, peer_addr.ip()).await;
+                stats.increment_ip_reservation_rollback_tcp_limit_total();
+            }
             return Err(ProxyError::ConnectionLimitExceeded {
                 user: user.to_string(),
             });
@@ -776,6 +809,10 @@ impl RunningClientHandler {
         if let Some(quota) = config.access.user_data_quota.get(user)
             && stats.get_user_total_octets(user) >= *quota
         {
+            if ip_reserved {
+                ip_tracker.remove_ip(user, peer_addr.ip()).await;
+                stats.increment_ip_reservation_rollback_quota_limit_total();
+            }
             return Err(ProxyError::DataQuotaExceeded {
                 user: user.to_string(),
             });

src/proxy/direct_relay.rs

@@ -34,7 +34,7 @@ where
     let user = &success.user;
     let dc_addr = get_dc_addr_static(success.dc_idx, &config)?;
 
-    info!(
+    debug!(
         user = %user,
         peer = %success.peer,
         dc = success.dc_idx,
@@ -57,6 +57,7 @@ where
 
     stats.increment_user_connects(user);
     stats.increment_user_curr_connects(user);
+    stats.increment_current_connections_direct();
 
     let relay_result = relay_bidirectional(
         client_reader,
@@ -69,6 +70,7 @@ where
     )
     .await;
 
+    stats.decrement_current_connections_direct();
     stats.decrement_user_curr_connects(user);
 
     match &relay_result {
@@ -118,10 +120,16 @@ fn get_dc_addr_static(dc_idx: i16, config: &ProxyConfig) -> Result<SocketAddr> {
     // Unknown DC requested by client without override: log and fall back.
     if !config.dc_overrides.contains_key(&dc_key) {
         warn!(dc_idx = dc_idx, "Requested non-standard DC with no override; falling back to default cluster");
-        if let Some(path) = &config.general.unknown_dc_log_path
-            && let Ok(mut file) = OpenOptions::new().create(true).append(true).open(path)
+        if config.general.unknown_dc_file_log_enabled
+            && let Some(path) = &config.general.unknown_dc_log_path
+            && let Ok(handle) = tokio::runtime::Handle::try_current()
         {
-            let _ = writeln!(file, "dc_idx={dc_idx}");
+            let path = path.clone();
+            handle.spawn_blocking(move || {
+                if let Ok(mut file) = OpenOptions::new().create(true).append(true).open(path) {
+                    let _ = writeln!(file, "dc_idx={dc_idx}");
+                }
+            });
         }
     }
 

src/proxy/handshake.rs

@@ -6,7 +6,7 @@ use std::net::SocketAddr;
 use std::sync::Arc;
 use std::time::Duration;
 use tokio::io::{AsyncRead, AsyncWrite, AsyncWriteExt};
-use tracing::{debug, warn, trace, info};
+use tracing::{debug, warn, trace};
 use zeroize::Zeroize;
 
 use crate::crypto::{sha256, AesCtr, SecureRandom};
@@ -19,6 +19,31 @@ use crate::stats::ReplayChecker;
 use crate::config::ProxyConfig;
 use crate::tls_front::{TlsFrontCache, emulator};
 
+fn decode_user_secrets(
+    config: &ProxyConfig,
+    preferred_user: Option<&str>,
+) -> Vec<(String, Vec<u8>)> {
+    let mut secrets = Vec::with_capacity(config.access.users.len());
+
+    if let Some(preferred) = preferred_user
+        && let Some(secret_hex) = config.access.users.get(preferred)
+        && let Ok(bytes) = hex::decode(secret_hex)
+    {
+        secrets.push((preferred.to_string(), bytes));
+    }
+
+    for (name, secret_hex) in &config.access.users {
+        if preferred_user.is_some_and(|preferred| preferred == name.as_str()) {
+            continue;
+        }
+        if let Ok(bytes) = hex::decode(secret_hex) {
+            secrets.push((name.clone(), bytes));
+        }
+    }
+
+    secrets
+}
+
 /// Result of successful handshake
 ///
 /// Key material (`dec_key`, `dec_iv`, `enc_key`, `enc_iv`) is
@@ -82,11 +107,7 @@ where
         return HandshakeResult::BadClient { reader, writer };
     }
 
-    let secrets: Vec<(String, Vec<u8>)> = config.access.users.iter()
-        .filter_map(|(name, hex)| {
-            hex::decode(hex).ok().map(|bytes| (name.clone(), bytes))
-        })
-        .collect();
+    let secrets = decode_user_secrets(config, None);
 
     let validation = match tls::validate_tls_handshake(
         handshake,
@@ -201,7 +222,7 @@ where
         return HandshakeResult::Error(ProxyError::Io(e));
     }
 
-    info!(
+    debug!(
         peer = %peer,
         user = %validation.user,
         "TLS handshake successful"
@@ -223,6 +244,7 @@ pub async fn handle_mtproto_handshake<R, W>(
     config: &ProxyConfig,
     replay_checker: &ReplayChecker,
     is_tls: bool,
+    preferred_user: Option<&str>,
 ) -> HandshakeResult<(CryptoReader<R>, CryptoWriter<W>, HandshakeSuccess), R, W>
 where
     R: AsyncRead + Unpin + Send,
@@ -239,11 +261,9 @@ where
 
     let enc_prekey_iv: Vec<u8> = dec_prekey_iv.iter().rev().copied().collect();
 
-    for (user, secret_hex) in &config.access.users {
-        let secret = match hex::decode(secret_hex) {
-            Ok(s) => s,
-            Err(_) => continue,
-        };
+    let decoded_users = decode_user_secrets(config, preferred_user);
+
+    for (user, secret) in decoded_users {
 
         let dec_prekey = &dec_prekey_iv[..PREKEY_LEN];
         let dec_iv_bytes = &dec_prekey_iv[PREKEY_LEN..];
@@ -311,7 +331,7 @@ where
             is_tls,
         };
 
-        info!(
+        debug!(
             peer = %peer,
             user = %user,
             dc = dc_idx,

src/proxy/middle_relay.rs

@@ -6,9 +6,10 @@ use std::sync::atomic::{AtomicU64, Ordering};
 use std::sync::{Arc, Mutex, OnceLock};
 use std::time::{Duration, Instant};
 
+use bytes::Bytes;
 use tokio::io::{AsyncRead, AsyncReadExt, AsyncWrite, AsyncWriteExt};
 use tokio::sync::{mpsc, oneshot};
-use tracing::{debug, info, trace, warn};
+use tracing::{debug, trace, warn};
 
 use crate::config::ProxyConfig;
 use crate::crypto::SecureRandom;
@@ -20,13 +21,13 @@ use crate::stream::{BufferPool, CryptoReader, CryptoWriter};
 use crate::transport::middle_proxy::{MePool, MeResponse, proto_flags_for_tag};
 
 enum C2MeCommand {
-    Data { payload: Vec<u8>, flags: u32 },
+    Data { payload: Bytes, flags: u32 },
     Close,
 }
 
 const DESYNC_DEDUP_WINDOW: Duration = Duration::from_secs(60);
 const DESYNC_ERROR_CLASS: &str = "frame_too_large_crypto_desync";
-const C2ME_CHANNEL_CAPACITY: usize = 1024;
+const C2ME_CHANNEL_CAPACITY_FALLBACK: usize = 128;
 const C2ME_SOFT_PRESSURE_MIN_FREE_SLOTS: usize = 64;
 const C2ME_SENDER_FAIRNESS_BUDGET: usize = 32;
 static DESYNC_DEDUP: OnceLock<Mutex<HashMap<u64, Instant>>> = OnceLock::new();
@@ -210,7 +211,7 @@ where
     let proto_tag = success.proto_tag;
     let pool_generation = me_pool.current_generation();
 
-    info!(
+    debug!(
         user = %user,
         peer = %peer,
         dc = success.dc_idx,
@@ -237,6 +238,7 @@ where
 
     stats.increment_user_connects(&user);
     stats.increment_user_curr_connects(&user);
+    stats.increment_current_connections_me();
 
     // Per-user ad_tag from access.user_ad_tags; fallback to general.ad_tag (hot-reloadable)
     let user_tag: Option<Vec<u8>> = config
@@ -269,7 +271,11 @@ where
 
     let frame_limit = config.general.max_client_frame;
 
-    let (c2me_tx, mut c2me_rx) = mpsc::channel::<C2MeCommand>(C2ME_CHANNEL_CAPACITY);
+    let c2me_channel_capacity = config
+        .general
+        .me_c2me_channel_capacity
+        .max(C2ME_CHANNEL_CAPACITY_FALLBACK);
+    let (c2me_tx, mut c2me_rx) = mpsc::channel::<C2MeCommand>(c2me_channel_capacity);
     let me_pool_c2me = me_pool.clone();
     let effective_tag = effective_tag;
     let c2me_sender = tokio::spawn(async move {
@@ -282,7 +288,7 @@ where
                         success.dc_idx,
                         peer,
                         translated_local_addr,
-                        &payload,
+                        payload.as_ref(),
                         flags,
                         effective_tag.as_deref(),
                     ).await?;
@@ -466,6 +472,7 @@ where
         "ME relay cleanup"
     );
     me_pool.registry().unregister(conn_id).await;
+    stats.decrement_current_connections_me();
     stats.decrement_user_curr_connects(&user);
     result
 }
@@ -477,7 +484,7 @@ async fn read_client_payload<R>(
     forensics: &RelayForensicsState,
     frame_counter: &mut u64,
     stats: &Stats,
-) -> Result<Option<(Vec<u8>, bool)>>
+) -> Result<Option<(Bytes, bool)>>
 where
     R: AsyncRead + Unpin + Send + 'static,
 {
@@ -576,7 +583,7 @@ where
             payload.truncate(secure_payload_len);
         }
         *frame_counter += 1;
-        return Ok(Some((payload, quickack)));
+        return Ok(Some((Bytes::from(payload), quickack)));
     }
 }
 
@@ -713,7 +720,7 @@ mod tests {
         enqueue_c2me_command(
             &tx,
             C2MeCommand::Data {
-                payload: vec![1, 2, 3],
+                payload: Bytes::from_static(&[1, 2, 3]),
                 flags: 0,
             },
         )
@@ -726,7 +733,7 @@ mod tests {
             .unwrap();
         match recv {
             C2MeCommand::Data { payload, flags } => {
-                assert_eq!(payload, vec![1, 2, 3]);
+                assert_eq!(payload.as_ref(), &[1, 2, 3]);
                 assert_eq!(flags, 0);
             }
             C2MeCommand::Close => panic!("unexpected close command"),
@@ -737,7 +744,7 @@ mod tests {
     async fn enqueue_c2me_command_falls_back_to_send_when_queue_is_full() {
         let (tx, mut rx) = mpsc::channel::<C2MeCommand>(1);
         tx.send(C2MeCommand::Data {
-            payload: vec![9],
+            payload: Bytes::from_static(&[9]),
             flags: 9,
         })
         .await
@@ -748,7 +755,7 @@ mod tests {
             enqueue_c2me_command(
                 &tx2,
                 C2MeCommand::Data {
-                    payload: vec![7, 7],
+                    payload: Bytes::from_static(&[7, 7]),
                     flags: 7,
                 },
             )
@@ -767,7 +774,7 @@ mod tests {
             .unwrap();
         match recv {
             C2MeCommand::Data { payload, flags } => {
-                assert_eq!(payload, vec![7, 7]);
+                assert_eq!(payload.as_ref(), &[7, 7]);
                 assert_eq!(flags, 7);
             }
             C2MeCommand::Close => panic!("unexpected close command"),

src/startup.rs

@@ -0,0 +1,373 @@
+use std::time::{Instant, SystemTime, UNIX_EPOCH};
+
+use tokio::sync::RwLock;
+
+pub const COMPONENT_CONFIG_LOAD: &str = "config_load";
+pub const COMPONENT_TRACING_INIT: &str = "tracing_init";
+pub const COMPONENT_API_BOOTSTRAP: &str = "api_bootstrap";
+pub const COMPONENT_TLS_FRONT_BOOTSTRAP: &str = "tls_front_bootstrap";
+pub const COMPONENT_NETWORK_PROBE: &str = "network_probe";
+pub const COMPONENT_ME_SECRET_FETCH: &str = "me_secret_fetch";
+pub const COMPONENT_ME_PROXY_CONFIG_V4: &str = "me_proxy_config_fetch_v4";
+pub const COMPONENT_ME_PROXY_CONFIG_V6: &str = "me_proxy_config_fetch_v6";
+pub const COMPONENT_ME_POOL_CONSTRUCT: &str = "me_pool_construct";
+pub const COMPONENT_ME_POOL_INIT_STAGE1: &str = "me_pool_init_stage1";
+pub const COMPONENT_ME_CONNECTIVITY_PING: &str = "me_connectivity_ping";
+pub const COMPONENT_DC_CONNECTIVITY_PING: &str = "dc_connectivity_ping";
+pub const COMPONENT_LISTENERS_BIND: &str = "listeners_bind";
+pub const COMPONENT_CONFIG_WATCHER_START: &str = "config_watcher_start";
+pub const COMPONENT_METRICS_START: &str = "metrics_start";
+pub const COMPONENT_RUNTIME_READY: &str = "runtime_ready";
+
+#[derive(Clone, Copy, Debug, PartialEq, Eq)]
+pub enum StartupStatus {
+    Initializing,
+    Ready,
+}
+
+impl StartupStatus {
+    pub fn as_str(self) -> &'static str {
+        match self {
+            Self::Initializing => "initializing",
+            Self::Ready => "ready",
+        }
+    }
+}
+
+#[derive(Clone, Copy, Debug, PartialEq, Eq)]
+pub enum StartupComponentStatus {
+    Pending,
+    Running,
+    Ready,
+    Failed,
+    Skipped,
+}
+
+impl StartupComponentStatus {
+    pub fn as_str(self) -> &'static str {
+        match self {
+            Self::Pending => "pending",
+            Self::Running => "running",
+            Self::Ready => "ready",
+            Self::Failed => "failed",
+            Self::Skipped => "skipped",
+        }
+    }
+}
+
+#[derive(Clone, Copy, Debug, PartialEq, Eq)]
+pub enum StartupMeStatus {
+    Pending,
+    Initializing,
+    Ready,
+    Failed,
+    Skipped,
+}
+
+impl StartupMeStatus {
+    pub fn as_str(self) -> &'static str {
+        match self {
+            Self::Pending => "pending",
+            Self::Initializing => "initializing",
+            Self::Ready => "ready",
+            Self::Failed => "failed",
+            Self::Skipped => "skipped",
+        }
+    }
+}
+
+#[derive(Clone, Debug)]
+pub struct StartupComponentSnapshot {
+    pub id: &'static str,
+    pub title: &'static str,
+    pub weight: f64,
+    pub status: StartupComponentStatus,
+    pub started_at_epoch_ms: Option<u64>,
+    pub finished_at_epoch_ms: Option<u64>,
+    pub duration_ms: Option<u64>,
+    pub attempts: u32,
+    pub details: Option<String>,
+}
+
+#[derive(Clone, Debug)]
+pub struct StartupMeSnapshot {
+    pub status: StartupMeStatus,
+    pub current_stage: String,
+    pub init_attempt: u32,
+    pub retry_limit: String,
+    pub last_error: Option<String>,
+}
+
+#[derive(Clone, Debug)]
+pub struct StartupSnapshot {
+    pub status: StartupStatus,
+    pub degraded: bool,
+    pub current_stage: String,
+    pub started_at_epoch_secs: u64,
+    pub ready_at_epoch_secs: Option<u64>,
+    pub total_elapsed_ms: u64,
+    pub transport_mode: String,
+    pub me: StartupMeSnapshot,
+    pub components: Vec<StartupComponentSnapshot>,
+}
+
+#[derive(Clone, Debug)]
+struct StartupComponent {
+    id: &'static str,
+    title: &'static str,
+    weight: f64,
+    status: StartupComponentStatus,
+    started_at_epoch_ms: Option<u64>,
+    finished_at_epoch_ms: Option<u64>,
+    duration_ms: Option<u64>,
+    attempts: u32,
+    details: Option<String>,
+}
+
+#[derive(Clone, Debug)]
+struct StartupState {
+    status: StartupStatus,
+    degraded: bool,
+    current_stage: String,
+    started_at_epoch_secs: u64,
+    ready_at_epoch_secs: Option<u64>,
+    transport_mode: String,
+    me: StartupMeSnapshot,
+    components: Vec<StartupComponent>,
+}
+
+pub struct StartupTracker {
+    started_at_instant: Instant,
+    state: RwLock<StartupState>,
+}
+
+impl StartupTracker {
+    pub fn new(started_at_epoch_secs: u64) -> Self {
+        Self {
+            started_at_instant: Instant::now(),
+            state: RwLock::new(StartupState {
+                status: StartupStatus::Initializing,
+                degraded: false,
+                current_stage: COMPONENT_CONFIG_LOAD.to_string(),
+                started_at_epoch_secs,
+                ready_at_epoch_secs: None,
+                transport_mode: "unknown".to_string(),
+                me: StartupMeSnapshot {
+                    status: StartupMeStatus::Pending,
+                    current_stage: "pending".to_string(),
+                    init_attempt: 0,
+                    retry_limit: "unlimited".to_string(),
+                    last_error: None,
+                },
+                components: component_blueprint(),
+            }),
+        }
+    }
+
+    pub async fn set_transport_mode(&self, mode: &'static str) {
+        self.state.write().await.transport_mode = mode.to_string();
+    }
+
+    pub async fn set_degraded(&self, degraded: bool) {
+        self.state.write().await.degraded = degraded;
+    }
+
+    pub async fn start_component(&self, id: &'static str, details: Option<String>) {
+        let mut guard = self.state.write().await;
+        guard.current_stage = id.to_string();
+        if let Some(component) = guard.components.iter_mut().find(|component| component.id == id) {
+            if component.started_at_epoch_ms.is_none() {
+                component.started_at_epoch_ms = Some(now_epoch_ms());
+            }
+            component.attempts = component.attempts.saturating_add(1);
+            component.status = StartupComponentStatus::Running;
+            component.details = normalize_details(details);
+        }
+    }
+
+    pub async fn complete_component(&self, id: &'static str, details: Option<String>) {
+        self.finish_component(id, StartupComponentStatus::Ready, details)
+            .await;
+    }
+
+    pub async fn fail_component(&self, id: &'static str, details: Option<String>) {
+        self.finish_component(id, StartupComponentStatus::Failed, details)
+            .await;
+    }
+
+    pub async fn skip_component(&self, id: &'static str, details: Option<String>) {
+        self.finish_component(id, StartupComponentStatus::Skipped, details)
+            .await;
+    }
+
+    async fn finish_component(
+        &self,
+        id: &'static str,
+        status: StartupComponentStatus,
+        details: Option<String>,
+    ) {
+        let mut guard = self.state.write().await;
+        let finished_at = now_epoch_ms();
+        if let Some(component) = guard.components.iter_mut().find(|component| component.id == id) {
+            if component.started_at_epoch_ms.is_none() {
+                component.started_at_epoch_ms = Some(finished_at);
+                component.attempts = component.attempts.saturating_add(1);
+            }
+            component.finished_at_epoch_ms = Some(finished_at);
+            component.duration_ms = component
+                .started_at_epoch_ms
+                .map(|started_at| finished_at.saturating_sub(started_at));
+            component.status = status;
+            component.details = normalize_details(details);
+        }
+    }
+
+    pub async fn set_me_status(&self, status: StartupMeStatus, stage: &'static str) {
+        let mut guard = self.state.write().await;
+        guard.me.status = status;
+        guard.me.current_stage = stage.to_string();
+    }
+
+    pub async fn set_me_retry_limit(&self, retry_limit: String) {
+        self.state.write().await.me.retry_limit = retry_limit;
+    }
+
+    pub async fn set_me_init_attempt(&self, attempt: u32) {
+        self.state.write().await.me.init_attempt = attempt;
+    }
+
+    pub async fn set_me_last_error(&self, error: Option<String>) {
+        self.state.write().await.me.last_error = normalize_details(error);
+    }
+
+    pub async fn mark_ready(&self) {
+        let mut guard = self.state.write().await;
+        if guard.status == StartupStatus::Ready {
+            return;
+        }
+        guard.status = StartupStatus::Ready;
+        guard.current_stage = "ready".to_string();
+        guard.ready_at_epoch_secs = Some(now_epoch_secs());
+    }
+
+    pub async fn snapshot(&self) -> StartupSnapshot {
+        let guard = self.state.read().await;
+        StartupSnapshot {
+            status: guard.status,
+            degraded: guard.degraded,
+            current_stage: guard.current_stage.clone(),
+            started_at_epoch_secs: guard.started_at_epoch_secs,
+            ready_at_epoch_secs: guard.ready_at_epoch_secs,
+            total_elapsed_ms: self.started_at_instant.elapsed().as_millis() as u64,
+            transport_mode: guard.transport_mode.clone(),
+            me: guard.me.clone(),
+            components: guard
+                .components
+                .iter()
+                .map(|component| StartupComponentSnapshot {
+                    id: component.id,
+                    title: component.title,
+                    weight: component.weight,
+                    status: component.status,
+                    started_at_epoch_ms: component.started_at_epoch_ms,
+                    finished_at_epoch_ms: component.finished_at_epoch_ms,
+                    duration_ms: component.duration_ms,
+                    attempts: component.attempts,
+                    details: component.details.clone(),
+                })
+                .collect(),
+        }
+    }
+}
+
+pub fn compute_progress_pct(snapshot: &StartupSnapshot, me_stage_progress: Option<f64>) -> f64 {
+    if snapshot.status == StartupStatus::Ready {
+        return 100.0;
+    }
+
+    let mut total_weight = 0.0f64;
+    let mut completed_weight = 0.0f64;
+
+    for component in &snapshot.components {
+        total_weight += component.weight;
+        let unit_progress = match component.status {
+            StartupComponentStatus::Pending => 0.0,
+            StartupComponentStatus::Running => {
+                if component.id == COMPONENT_ME_POOL_INIT_STAGE1 {
+                    me_stage_progress.unwrap_or(0.0).clamp(0.0, 1.0)
+                } else {
+                    0.0
+                }
+            }
+            StartupComponentStatus::Ready
+            | StartupComponentStatus::Failed
+            | StartupComponentStatus::Skipped => 1.0,
+        };
+        completed_weight += component.weight * unit_progress;
+    }
+
+    if total_weight <= f64::EPSILON {
+        0.0
+    } else {
+        ((completed_weight / total_weight) * 100.0).clamp(0.0, 100.0)
+    }
+}
+
+fn component_blueprint() -> Vec<StartupComponent> {
+    vec![
+        component(COMPONENT_CONFIG_LOAD, "Config load", 5.0),
+        component(COMPONENT_TRACING_INIT, "Tracing init", 3.0),
+        component(COMPONENT_API_BOOTSTRAP, "API bootstrap", 5.0),
+        component(COMPONENT_TLS_FRONT_BOOTSTRAP, "TLS front bootstrap", 5.0),
+        component(COMPONENT_NETWORK_PROBE, "Network probe", 10.0),
+        component(COMPONENT_ME_SECRET_FETCH, "ME secret fetch", 8.0),
+        component(COMPONENT_ME_PROXY_CONFIG_V4, "ME config v4 fetch", 4.0),
+        component(COMPONENT_ME_PROXY_CONFIG_V6, "ME config v6 fetch", 4.0),
+        component(COMPONENT_ME_POOL_CONSTRUCT, "ME pool construct", 6.0),
+        component(COMPONENT_ME_POOL_INIT_STAGE1, "ME pool init stage1", 24.0),
+        component(COMPONENT_ME_CONNECTIVITY_PING, "ME connectivity ping", 6.0),
+        component(COMPONENT_DC_CONNECTIVITY_PING, "DC connectivity ping", 8.0),
+        component(COMPONENT_LISTENERS_BIND, "Listener bind", 8.0),
+        component(COMPONENT_CONFIG_WATCHER_START, "Config watcher start", 2.0),
+        component(COMPONENT_METRICS_START, "Metrics start", 1.0),
+        component(COMPONENT_RUNTIME_READY, "Runtime ready", 1.0),
+    ]
+}
+
+fn component(id: &'static str, title: &'static str, weight: f64) -> StartupComponent {
+    StartupComponent {
+        id,
+        title,
+        weight,
+        status: StartupComponentStatus::Pending,
+        started_at_epoch_ms: None,
+        finished_at_epoch_ms: None,
+        duration_ms: None,
+        attempts: 0,
+        details: None,
+    }
+}
+
+fn normalize_details(details: Option<String>) -> Option<String> {
+    details.map(|detail| {
+        if detail.len() <= 256 {
+            detail
+        } else {
+            detail[..256].to_string()
+        }
+    })
+}
+
+fn now_epoch_secs() -> u64 {
+    SystemTime::now()
+        .duration_since(UNIX_EPOCH)
+        .unwrap_or_default()
+        .as_secs()
+}
+
+fn now_epoch_ms() -> u64 {
+    SystemTime::now()
+        .duration_since(UNIX_EPOCH)
+        .unwrap_or_default()
+        .as_millis() as u64
+}

src/stats/mod.rs

@@ -6,7 +6,7 @@ pub mod beobachten;
 pub mod telemetry;
 
 use std::sync::atomic::{AtomicBool, AtomicU8, AtomicU64, Ordering};
-use std::time::{Instant, Duration};
+use std::time::{Duration, Instant, SystemTime, UNIX_EPOCH};
 use dashmap::DashMap;
 use parking_lot::Mutex;
 use lru::LruCache;
@@ -25,6 +25,8 @@ use self::telemetry::TelemetryPolicy;
 pub struct Stats {
     connects_all: AtomicU64,
     connects_bad: AtomicU64,
+    current_connections_direct: AtomicU64,
+    current_connections_me: AtomicU64,
     handshake_timeouts: AtomicU64,
     upstream_connect_attempt_total: AtomicU64,
     upstream_connect_success_total: AtomicU64,
@@ -73,6 +75,20 @@ pub struct Stats {
     me_floor_mode_switch_total: AtomicU64,
     me_floor_mode_switch_static_to_adaptive_total: AtomicU64,
     me_floor_mode_switch_adaptive_to_static_total: AtomicU64,
+    me_floor_cpu_cores_detected_gauge: AtomicU64,
+    me_floor_cpu_cores_effective_gauge: AtomicU64,
+    me_floor_global_cap_raw_gauge: AtomicU64,
+    me_floor_global_cap_effective_gauge: AtomicU64,
+    me_floor_target_writers_total_gauge: AtomicU64,
+    me_floor_active_cap_configured_gauge: AtomicU64,
+    me_floor_active_cap_effective_gauge: AtomicU64,
+    me_floor_warm_cap_configured_gauge: AtomicU64,
+    me_floor_warm_cap_effective_gauge: AtomicU64,
+    me_writers_active_current_gauge: AtomicU64,
+    me_writers_warm_current_gauge: AtomicU64,
+    me_floor_cap_block_total: AtomicU64,
+    me_floor_swap_idle_total: AtomicU64,
+    me_floor_swap_idle_failed_total: AtomicU64,
     me_handshake_error_codes: DashMap<i32, AtomicU64>,
     me_route_drop_no_conn: AtomicU64,
     me_route_drop_channel_closed: AtomicU64,
@@ -100,10 +116,16 @@ pub struct Stats {
     me_refill_failed_total: AtomicU64,
     me_writer_restored_same_endpoint_total: AtomicU64,
     me_writer_restored_fallback_total: AtomicU64,
+    me_no_writer_failfast_total: AtomicU64,
+    me_async_recovery_trigger_total: AtomicU64,
+    me_inline_recovery_total: AtomicU64,
+    ip_reservation_rollback_tcp_limit_total: AtomicU64,
+    ip_reservation_rollback_quota_limit_total: AtomicU64,
     telemetry_core_enabled: AtomicBool,
     telemetry_user_enabled: AtomicBool,
     telemetry_me_level: AtomicU8,
     user_stats: DashMap<String, UserStats>,
+    user_stats_last_cleanup_epoch_secs: AtomicU64,
     start_time: parking_lot::RwLock<Option<Instant>>,
 }
 
@@ -115,6 +137,7 @@ pub struct UserStats {
     pub octets_to_client: AtomicU64,
     pub msgs_from_client: AtomicU64,
     pub msgs_to_client: AtomicU64,
+    pub last_seen_epoch_secs: AtomicU64,
 }
 
 impl Stats {
@@ -145,6 +168,72 @@ impl Stats {
         self.telemetry_me_level().allows_debug()
     }
 
+    fn decrement_atomic_saturating(counter: &AtomicU64) {
+        let mut current = counter.load(Ordering::Relaxed);
+        loop {
+            if current == 0 {
+                break;
+            }
+            match counter.compare_exchange_weak(
+                current,
+                current - 1,
+                Ordering::Relaxed,
+                Ordering::Relaxed,
+            ) {
+                Ok(_) => break,
+                Err(actual) => current = actual,
+            }
+        }
+    }
+
+    fn now_epoch_secs() -> u64 {
+        SystemTime::now()
+            .duration_since(UNIX_EPOCH)
+            .unwrap_or_default()
+            .as_secs()
+    }
+
+    fn touch_user_stats(stats: &UserStats) {
+        stats
+            .last_seen_epoch_secs
+            .store(Self::now_epoch_secs(), Ordering::Relaxed);
+    }
+
+    fn maybe_cleanup_user_stats(&self) {
+        const USER_STATS_CLEANUP_INTERVAL_SECS: u64 = 60;
+        const USER_STATS_IDLE_TTL_SECS: u64 = 24 * 60 * 60;
+
+        let now_epoch_secs = Self::now_epoch_secs();
+        let last_cleanup_epoch_secs = self
+            .user_stats_last_cleanup_epoch_secs
+            .load(Ordering::Relaxed);
+        if now_epoch_secs.saturating_sub(last_cleanup_epoch_secs)
+            < USER_STATS_CLEANUP_INTERVAL_SECS
+        {
+            return;
+        }
+        if self
+            .user_stats_last_cleanup_epoch_secs
+            .compare_exchange(
+                last_cleanup_epoch_secs,
+                now_epoch_secs,
+                Ordering::AcqRel,
+                Ordering::Relaxed,
+            )
+            .is_err()
+        {
+            return;
+        }
+
+        self.user_stats.retain(|_, stats| {
+            if stats.curr_connects.load(Ordering::Relaxed) > 0 {
+                return true;
+            }
+            let last_seen_epoch_secs = stats.last_seen_epoch_secs.load(Ordering::Relaxed);
+            now_epoch_secs.saturating_sub(last_seen_epoch_secs) <= USER_STATS_IDLE_TTL_SECS
+        });
+    }
+
     pub fn apply_telemetry_policy(&self, policy: TelemetryPolicy) {
         self.telemetry_core_enabled
             .store(policy.core_enabled, Ordering::Relaxed);
@@ -172,6 +261,18 @@ impl Stats {
             self.connects_bad.fetch_add(1, Ordering::Relaxed);
         }
     }
+    pub fn increment_current_connections_direct(&self) {
+        self.current_connections_direct.fetch_add(1, Ordering::Relaxed);
+    }
+    pub fn decrement_current_connections_direct(&self) {
+        Self::decrement_atomic_saturating(&self.current_connections_direct);
+    }
+    pub fn increment_current_connections_me(&self) {
+        self.current_connections_me.fetch_add(1, Ordering::Relaxed);
+    }
+    pub fn decrement_current_connections_me(&self) {
+        Self::decrement_atomic_saturating(&self.current_connections_me);
+    }
     pub fn increment_handshake_timeouts(&self) {
         if self.telemetry_core_enabled() {
             self.handshake_timeouts.fetch_add(1, Ordering::Relaxed);
@@ -522,6 +623,34 @@ impl Stats {
                 .fetch_add(1, Ordering::Relaxed);
         }
     }
+    pub fn increment_me_no_writer_failfast_total(&self) {
+        if self.telemetry_me_allows_normal() {
+            self.me_no_writer_failfast_total.fetch_add(1, Ordering::Relaxed);
+        }
+    }
+    pub fn increment_me_async_recovery_trigger_total(&self) {
+        if self.telemetry_me_allows_normal() {
+            self.me_async_recovery_trigger_total
+                .fetch_add(1, Ordering::Relaxed);
+        }
+    }
+    pub fn increment_me_inline_recovery_total(&self) {
+        if self.telemetry_me_allows_normal() {
+            self.me_inline_recovery_total.fetch_add(1, Ordering::Relaxed);
+        }
+    }
+    pub fn increment_ip_reservation_rollback_tcp_limit_total(&self) {
+        if self.telemetry_core_enabled() {
+            self.ip_reservation_rollback_tcp_limit_total
+                .fetch_add(1, Ordering::Relaxed);
+        }
+    }
+    pub fn increment_ip_reservation_rollback_quota_limit_total(&self) {
+        if self.telemetry_core_enabled() {
+            self.ip_reservation_rollback_quota_limit_total
+                .fetch_add(1, Ordering::Relaxed);
+        }
+    }
     pub fn increment_me_endpoint_quarantine_total(&self) {
         if self.telemetry_me_allows_normal() {
             self.me_endpoint_quarantine_total
@@ -611,8 +740,100 @@ impl Stats {
                 .fetch_add(1, Ordering::Relaxed);
         }
     }
+    pub fn set_me_floor_cpu_cores_detected_gauge(&self, value: u64) {
+        if self.telemetry_me_allows_normal() {
+            self.me_floor_cpu_cores_detected_gauge
+                .store(value, Ordering::Relaxed);
+        }
+    }
+    pub fn set_me_floor_cpu_cores_effective_gauge(&self, value: u64) {
+        if self.telemetry_me_allows_normal() {
+            self.me_floor_cpu_cores_effective_gauge
+                .store(value, Ordering::Relaxed);
+        }
+    }
+    pub fn set_me_floor_global_cap_raw_gauge(&self, value: u64) {
+        if self.telemetry_me_allows_normal() {
+            self.me_floor_global_cap_raw_gauge
+                .store(value, Ordering::Relaxed);
+        }
+    }
+    pub fn set_me_floor_global_cap_effective_gauge(&self, value: u64) {
+        if self.telemetry_me_allows_normal() {
+            self.me_floor_global_cap_effective_gauge
+                .store(value, Ordering::Relaxed);
+        }
+    }
+    pub fn set_me_floor_target_writers_total_gauge(&self, value: u64) {
+        if self.telemetry_me_allows_normal() {
+            self.me_floor_target_writers_total_gauge
+                .store(value, Ordering::Relaxed);
+        }
+    }
+    pub fn set_me_floor_active_cap_configured_gauge(&self, value: u64) {
+        if self.telemetry_me_allows_normal() {
+            self.me_floor_active_cap_configured_gauge
+                .store(value, Ordering::Relaxed);
+        }
+    }
+    pub fn set_me_floor_active_cap_effective_gauge(&self, value: u64) {
+        if self.telemetry_me_allows_normal() {
+            self.me_floor_active_cap_effective_gauge
+                .store(value, Ordering::Relaxed);
+        }
+    }
+    pub fn set_me_floor_warm_cap_configured_gauge(&self, value: u64) {
+        if self.telemetry_me_allows_normal() {
+            self.me_floor_warm_cap_configured_gauge
+                .store(value, Ordering::Relaxed);
+        }
+    }
+    pub fn set_me_floor_warm_cap_effective_gauge(&self, value: u64) {
+        if self.telemetry_me_allows_normal() {
+            self.me_floor_warm_cap_effective_gauge
+                .store(value, Ordering::Relaxed);
+        }
+    }
+    pub fn set_me_writers_active_current_gauge(&self, value: u64) {
+        if self.telemetry_me_allows_normal() {
+            self.me_writers_active_current_gauge
+                .store(value, Ordering::Relaxed);
+        }
+    }
+    pub fn set_me_writers_warm_current_gauge(&self, value: u64) {
+        if self.telemetry_me_allows_normal() {
+            self.me_writers_warm_current_gauge
+                .store(value, Ordering::Relaxed);
+        }
+    }
+    pub fn increment_me_floor_cap_block_total(&self) {
+        if self.telemetry_me_allows_normal() {
+            self.me_floor_cap_block_total.fetch_add(1, Ordering::Relaxed);
+        }
+    }
+    pub fn increment_me_floor_swap_idle_total(&self) {
+        if self.telemetry_me_allows_normal() {
+            self.me_floor_swap_idle_total.fetch_add(1, Ordering::Relaxed);
+        }
+    }
+    pub fn increment_me_floor_swap_idle_failed_total(&self) {
+        if self.telemetry_me_allows_normal() {
+            self.me_floor_swap_idle_failed_total
+                .fetch_add(1, Ordering::Relaxed);
+        }
+    }
     pub fn get_connects_all(&self) -> u64 { self.connects_all.load(Ordering::Relaxed) }
     pub fn get_connects_bad(&self) -> u64 { self.connects_bad.load(Ordering::Relaxed) }
+    pub fn get_current_connections_direct(&self) -> u64 {
+        self.current_connections_direct.load(Ordering::Relaxed)
+    }
+    pub fn get_current_connections_me(&self) -> u64 {
+        self.current_connections_me.load(Ordering::Relaxed)
+    }
+    pub fn get_current_connections_total(&self) -> u64 {
+        self.get_current_connections_direct()
+            .saturating_add(self.get_current_connections_me())
+    }
     pub fn get_me_keepalive_sent(&self) -> u64 { self.me_keepalive_sent.load(Ordering::Relaxed) }
     pub fn get_me_keepalive_failed(&self) -> u64 { self.me_keepalive_failed.load(Ordering::Relaxed) }
     pub fn get_me_keepalive_pong(&self) -> u64 { self.me_keepalive_pong.load(Ordering::Relaxed) }
@@ -706,6 +927,58 @@ impl Stats {
         self.me_floor_mode_switch_adaptive_to_static_total
             .load(Ordering::Relaxed)
     }
+    pub fn get_me_floor_cpu_cores_detected_gauge(&self) -> u64 {
+        self.me_floor_cpu_cores_detected_gauge
+            .load(Ordering::Relaxed)
+    }
+    pub fn get_me_floor_cpu_cores_effective_gauge(&self) -> u64 {
+        self.me_floor_cpu_cores_effective_gauge
+            .load(Ordering::Relaxed)
+    }
+    pub fn get_me_floor_global_cap_raw_gauge(&self) -> u64 {
+        self.me_floor_global_cap_raw_gauge.load(Ordering::Relaxed)
+    }
+    pub fn get_me_floor_global_cap_effective_gauge(&self) -> u64 {
+        self.me_floor_global_cap_effective_gauge
+            .load(Ordering::Relaxed)
+    }
+    pub fn get_me_floor_target_writers_total_gauge(&self) -> u64 {
+        self.me_floor_target_writers_total_gauge
+            .load(Ordering::Relaxed)
+    }
+    pub fn get_me_floor_active_cap_configured_gauge(&self) -> u64 {
+        self.me_floor_active_cap_configured_gauge
+            .load(Ordering::Relaxed)
+    }
+    pub fn get_me_floor_active_cap_effective_gauge(&self) -> u64 {
+        self.me_floor_active_cap_effective_gauge
+            .load(Ordering::Relaxed)
+    }
+    pub fn get_me_floor_warm_cap_configured_gauge(&self) -> u64 {
+        self.me_floor_warm_cap_configured_gauge
+            .load(Ordering::Relaxed)
+    }
+    pub fn get_me_floor_warm_cap_effective_gauge(&self) -> u64 {
+        self.me_floor_warm_cap_effective_gauge
+            .load(Ordering::Relaxed)
+    }
+    pub fn get_me_writers_active_current_gauge(&self) -> u64 {
+        self.me_writers_active_current_gauge
+            .load(Ordering::Relaxed)
+    }
+    pub fn get_me_writers_warm_current_gauge(&self) -> u64 {
+        self.me_writers_warm_current_gauge
+            .load(Ordering::Relaxed)
+    }
+    pub fn get_me_floor_cap_block_total(&self) -> u64 {
+        self.me_floor_cap_block_total.load(Ordering::Relaxed)
+    }
+    pub fn get_me_floor_swap_idle_total(&self) -> u64 {
+        self.me_floor_swap_idle_total.load(Ordering::Relaxed)
+    }
+    pub fn get_me_floor_swap_idle_failed_total(&self) -> u64 {
+        self.me_floor_swap_idle_failed_total.load(Ordering::Relaxed)
+    }
     pub fn get_me_handshake_error_code_counts(&self) -> Vec<(i32, u64)> {
         let mut out: Vec<(i32, u64)> = self
             .me_handshake_error_codes
@@ -791,25 +1064,58 @@ impl Stats {
     pub fn get_me_writer_restored_fallback_total(&self) -> u64 {
         self.me_writer_restored_fallback_total.load(Ordering::Relaxed)
     }
+    pub fn get_me_no_writer_failfast_total(&self) -> u64 {
+        self.me_no_writer_failfast_total.load(Ordering::Relaxed)
+    }
+    pub fn get_me_async_recovery_trigger_total(&self) -> u64 {
+        self.me_async_recovery_trigger_total.load(Ordering::Relaxed)
+    }
+    pub fn get_me_inline_recovery_total(&self) -> u64 {
+        self.me_inline_recovery_total.load(Ordering::Relaxed)
+    }
+    pub fn get_ip_reservation_rollback_tcp_limit_total(&self) -> u64 {
+        self.ip_reservation_rollback_tcp_limit_total
+            .load(Ordering::Relaxed)
+    }
+    pub fn get_ip_reservation_rollback_quota_limit_total(&self) -> u64 {
+        self.ip_reservation_rollback_quota_limit_total
+            .load(Ordering::Relaxed)
+    }
     
     pub fn increment_user_connects(&self, user: &str) {
         if !self.telemetry_user_enabled() {
             return;
         }
-        self.user_stats.entry(user.to_string()).or_default()
-            .connects.fetch_add(1, Ordering::Relaxed);
+        self.maybe_cleanup_user_stats();
+        if let Some(stats) = self.user_stats.get(user) {
+            Self::touch_user_stats(stats.value());
+            stats.connects.fetch_add(1, Ordering::Relaxed);
+            return;
+        }
+        let stats = self.user_stats.entry(user.to_string()).or_default();
+        Self::touch_user_stats(stats.value());
+        stats.connects.fetch_add(1, Ordering::Relaxed);
     }
     
     pub fn increment_user_curr_connects(&self, user: &str) {
         if !self.telemetry_user_enabled() {
             return;
         }
-        self.user_stats.entry(user.to_string()).or_default()
-            .curr_connects.fetch_add(1, Ordering::Relaxed);
+        self.maybe_cleanup_user_stats();
+        if let Some(stats) = self.user_stats.get(user) {
+            Self::touch_user_stats(stats.value());
+            stats.curr_connects.fetch_add(1, Ordering::Relaxed);
+            return;
+        }
+        let stats = self.user_stats.entry(user.to_string()).or_default();
+        Self::touch_user_stats(stats.value());
+        stats.curr_connects.fetch_add(1, Ordering::Relaxed);
     }
     
     pub fn decrement_user_curr_connects(&self, user: &str) {
+        self.maybe_cleanup_user_stats();
         if let Some(stats) = self.user_stats.get(user) {
+            Self::touch_user_stats(stats.value());
             let counter = &stats.curr_connects;
             let mut current = counter.load(Ordering::Relaxed);
             loop {
@@ -839,32 +1145,60 @@ impl Stats {
         if !self.telemetry_user_enabled() {
             return;
         }
-        self.user_stats.entry(user.to_string()).or_default()
-            .octets_from_client.fetch_add(bytes, Ordering::Relaxed);
+        self.maybe_cleanup_user_stats();
+        if let Some(stats) = self.user_stats.get(user) {
+            Self::touch_user_stats(stats.value());
+            stats.octets_from_client.fetch_add(bytes, Ordering::Relaxed);
+            return;
+        }
+        let stats = self.user_stats.entry(user.to_string()).or_default();
+        Self::touch_user_stats(stats.value());
+        stats.octets_from_client.fetch_add(bytes, Ordering::Relaxed);
     }
     
     pub fn add_user_octets_to(&self, user: &str, bytes: u64) {
         if !self.telemetry_user_enabled() {
             return;
         }
-        self.user_stats.entry(user.to_string()).or_default()
-            .octets_to_client.fetch_add(bytes, Ordering::Relaxed);
+        self.maybe_cleanup_user_stats();
+        if let Some(stats) = self.user_stats.get(user) {
+            Self::touch_user_stats(stats.value());
+            stats.octets_to_client.fetch_add(bytes, Ordering::Relaxed);
+            return;
+        }
+        let stats = self.user_stats.entry(user.to_string()).or_default();
+        Self::touch_user_stats(stats.value());
+        stats.octets_to_client.fetch_add(bytes, Ordering::Relaxed);
     }
     
     pub fn increment_user_msgs_from(&self, user: &str) {
         if !self.telemetry_user_enabled() {
             return;
         }
-        self.user_stats.entry(user.to_string()).or_default()
-            .msgs_from_client.fetch_add(1, Ordering::Relaxed);
+        self.maybe_cleanup_user_stats();
+        if let Some(stats) = self.user_stats.get(user) {
+            Self::touch_user_stats(stats.value());
+            stats.msgs_from_client.fetch_add(1, Ordering::Relaxed);
+            return;
+        }
+        let stats = self.user_stats.entry(user.to_string()).or_default();
+        Self::touch_user_stats(stats.value());
+        stats.msgs_from_client.fetch_add(1, Ordering::Relaxed);
     }
     
     pub fn increment_user_msgs_to(&self, user: &str) {
         if !self.telemetry_user_enabled() {
             return;
         }
-        self.user_stats.entry(user.to_string()).or_default()
-            .msgs_to_client.fetch_add(1, Ordering::Relaxed);
+        self.maybe_cleanup_user_stats();
+        if let Some(stats) = self.user_stats.get(user) {
+            Self::touch_user_stats(stats.value());
+            stats.msgs_to_client.fetch_add(1, Ordering::Relaxed);
+            return;
+        }
+        let stats = self.user_stats.entry(user.to_string()).or_default();
+        Self::touch_user_stats(stats.value());
+        stats.msgs_to_client.fetch_add(1, Ordering::Relaxed);
     }
     
     pub fn get_user_total_octets(&self, user: &str) -> u64 {

src/transport/middle_proxy/codec.rs

@@ -1,4 +1,5 @@
 use tokio::io::{AsyncReadExt, AsyncWriteExt};
+use bytes::Bytes;
 
 use crate::crypto::{AesCbc, crc32, crc32c};
 use crate::error::{ProxyError, Result};
@@ -6,8 +7,8 @@ use crate::protocol::constants::*;
 
 /// Commands sent to dedicated writer tasks to avoid mutex contention on TCP writes.
 pub(crate) enum WriterCommand {
-    Data(Vec<u8>),
-    DataAndFlush(Vec<u8>),
+    Data(Bytes),
+    DataAndFlush(Bytes),
     Close,
 }
 

src/transport/middle_proxy/config_updater.rs

@@ -1,6 +1,7 @@
 use std::collections::HashMap;
 use std::hash::{DefaultHasher, Hash, Hasher};
 use std::net::IpAddr;
+use std::path::Path;
 use std::sync::Arc;
 use std::time::Duration;
 
@@ -42,6 +43,87 @@ pub struct ProxyConfigData {
     pub proxy_for_lines: u32,
 }
 
+pub fn parse_proxy_config_text(text: &str, http_status: u16) -> ProxyConfigData {
+    let mut map: HashMap<i32, Vec<(IpAddr, u16)>> = HashMap::new();
+    let mut proxy_for_lines: u32 = 0;
+    for line in text.lines() {
+        if let Some((dc, ip, port)) = parse_proxy_line(line) {
+            map.entry(dc).or_default().push((ip, port));
+            proxy_for_lines = proxy_for_lines.saturating_add(1);
+        }
+    }
+
+    let default_dc = text.lines().find_map(|l| {
+        let t = l.trim();
+        if let Some(rest) = t.strip_prefix("default") {
+            return rest.trim().trim_end_matches(';').parse::<i32>().ok();
+        }
+        None
+    });
+
+    ProxyConfigData {
+        map,
+        default_dc,
+        http_status,
+        proxy_for_lines,
+    }
+}
+
+pub async fn load_proxy_config_cache(path: &str) -> Result<ProxyConfigData> {
+    let text = tokio::fs::read_to_string(path).await.map_err(|e| {
+        crate::error::ProxyError::Proxy(format!("read proxy-config cache '{path}' failed: {e}"))
+    })?;
+    Ok(parse_proxy_config_text(&text, 200))
+}
+
+pub async fn save_proxy_config_cache(path: &str, raw_text: &str) -> Result<()> {
+    if let Some(parent) = Path::new(path).parent()
+        && !parent.as_os_str().is_empty()
+    {
+        tokio::fs::create_dir_all(parent).await.map_err(|e| {
+            crate::error::ProxyError::Proxy(format!(
+                "create proxy-config cache dir '{}' failed: {e}",
+                parent.display()
+            ))
+        })?;
+    }
+
+    tokio::fs::write(path, raw_text).await.map_err(|e| {
+        crate::error::ProxyError::Proxy(format!("write proxy-config cache '{path}' failed: {e}"))
+    })?;
+    Ok(())
+}
+
+pub async fn fetch_proxy_config_with_raw(url: &str) -> Result<(ProxyConfigData, String)> {
+    let resp = reqwest::get(url)
+        .await
+        .map_err(|e| crate::error::ProxyError::Proxy(format!("fetch_proxy_config GET failed: {e}")))?
+        ;
+    let http_status = resp.status().as_u16();
+
+    if let Some(date) = resp.headers().get(reqwest::header::DATE)
+        && let Ok(date_str) = date.to_str()
+        && let Ok(server_time) = httpdate::parse_http_date(date_str)
+        && let Ok(skew) = SystemTime::now().duration_since(server_time).or_else(|e| {
+            server_time.duration_since(SystemTime::now()).map_err(|_| e)
+        })
+    {
+        let skew_secs = skew.as_secs();
+        if skew_secs > 60 {
+            warn!(skew_secs, "Time skew >60s detected from fetch_proxy_config Date header");
+        } else if skew_secs > 30 {
+            warn!(skew_secs, "Time skew >30s detected from fetch_proxy_config Date header");
+        }
+    }
+
+    let text = resp
+        .text()
+        .await
+        .map_err(|e| crate::error::ProxyError::Proxy(format!("fetch_proxy_config read failed: {e}")))?;
+    let parsed = parse_proxy_config_text(&text, http_status);
+    Ok((parsed, text))
+}
+
 #[derive(Debug, Default)]
 struct StableSnapshot {
     candidate_hash: Option<u64>,
@@ -170,61 +252,9 @@ fn parse_proxy_line(line: &str) -> Option<(i32, IpAddr, u16)> {
 }
 
 pub async fn fetch_proxy_config(url: &str) -> Result<ProxyConfigData> {
-    let resp = reqwest::get(url)
+    fetch_proxy_config_with_raw(url)
         .await
-        .map_err(|e| crate::error::ProxyError::Proxy(format!("fetch_proxy_config GET failed: {e}")))?
-        ;
-    let http_status = resp.status().as_u16();
-
-    if let Some(date) = resp.headers().get(reqwest::header::DATE)
-        && let Ok(date_str) = date.to_str()
-        && let Ok(server_time) = httpdate::parse_http_date(date_str)
-        && let Ok(skew) = SystemTime::now().duration_since(server_time).or_else(|e| {
-            server_time.duration_since(SystemTime::now()).map_err(|_| e)
-        })
-    {
-        let skew_secs = skew.as_secs();
-        if skew_secs > 60 {
-            warn!(skew_secs, "Time skew >60s detected from fetch_proxy_config Date header");
-        } else if skew_secs > 30 {
-            warn!(skew_secs, "Time skew >30s detected from fetch_proxy_config Date header");
-        }
-    }
-
-    let text = resp
-        .text()
-        .await
-        .map_err(|e| crate::error::ProxyError::Proxy(format!("fetch_proxy_config read failed: {e}")))?;
-
-    let mut map: HashMap<i32, Vec<(IpAddr, u16)>> = HashMap::new();
-    let mut proxy_for_lines: u32 = 0;
-    for line in text.lines() {
-        if let Some((dc, ip, port)) = parse_proxy_line(line) {
-            map.entry(dc).or_default().push((ip, port));
-            proxy_for_lines = proxy_for_lines.saturating_add(1);
-        }
-    }
-
-    let default_dc = text
-        .lines()
-        .find_map(|l| {
-            let t = l.trim();
-            if let Some(rest) = t.strip_prefix("default") {
-                return rest
-                    .trim()
-                    .trim_end_matches(';')
-                    .parse::<i32>()
-                    .ok();
-            }
-            None
-        });
-
-    Ok(ProxyConfigData {
-        map,
-        default_dc,
-        http_status,
-        proxy_for_lines,
-    })
+        .map(|(parsed, _raw)| parsed)
 }
 
 fn snapshot_passes_guards(
@@ -285,7 +315,19 @@ async fn run_update_cycle(
         cfg.general.me_floor_mode,
         cfg.general.me_adaptive_floor_idle_secs,
         cfg.general.me_adaptive_floor_min_writers_single_endpoint,
+        cfg.general.me_adaptive_floor_min_writers_multi_endpoint,
         cfg.general.me_adaptive_floor_recover_grace_secs,
+        cfg.general.me_adaptive_floor_writers_per_core_total,
+        cfg.general.me_adaptive_floor_cpu_cores_override,
+        cfg.general.me_adaptive_floor_max_extra_writers_single_per_core,
+        cfg.general.me_adaptive_floor_max_extra_writers_multi_per_core,
+        cfg.general.me_adaptive_floor_max_active_writers_per_core,
+        cfg.general.me_adaptive_floor_max_warm_writers_per_core,
+        cfg.general.me_adaptive_floor_max_active_writers_global,
+        cfg.general.me_adaptive_floor_max_warm_writers_global,
+        cfg.general.me_health_interval_ms_unhealthy,
+        cfg.general.me_health_interval_ms_healthy,
+        cfg.general.me_warn_rate_limit_ms,
     );
 
     let required_cfg_snapshots = cfg.general.me_config_stable_snapshots.max(1);
@@ -497,7 +539,19 @@ pub async fn me_config_updater(
                     cfg.general.me_floor_mode,
                     cfg.general.me_adaptive_floor_idle_secs,
                     cfg.general.me_adaptive_floor_min_writers_single_endpoint,
+                    cfg.general.me_adaptive_floor_min_writers_multi_endpoint,
                     cfg.general.me_adaptive_floor_recover_grace_secs,
+                    cfg.general.me_adaptive_floor_writers_per_core_total,
+                    cfg.general.me_adaptive_floor_cpu_cores_override,
+                    cfg.general.me_adaptive_floor_max_extra_writers_single_per_core,
+                    cfg.general.me_adaptive_floor_max_extra_writers_multi_per_core,
+                    cfg.general.me_adaptive_floor_max_active_writers_per_core,
+                    cfg.general.me_adaptive_floor_max_warm_writers_per_core,
+                    cfg.general.me_adaptive_floor_max_active_writers_global,
+                    cfg.general.me_adaptive_floor_max_warm_writers_global,
+                    cfg.general.me_health_interval_ms_unhealthy,
+                    cfg.general.me_health_interval_ms_healthy,
+                    cfg.general.me_warn_rate_limit_ms,
                 );
                 let new_secs = cfg.general.effective_update_every_secs().max(1);
                 if new_secs == update_every_secs {

src/transport/middle_proxy/handshake.rs

@@ -84,38 +84,7 @@ impl MePool {
     }
 
     async fn resolve_dc_idx_for_endpoint(&self, addr: SocketAddr) -> Option<i16> {
-        if addr.is_ipv4() {
-            let map = self.proxy_map_v4.read().await;
-            for (dc, addrs) in map.iter() {
-                if addrs
-                    .iter()
-                    .any(|(ip, port)| SocketAddr::new(*ip, *port) == addr)
-                {
-                    let abs_dc = dc.abs();
-                    if abs_dc > 0
-                        && let Ok(dc_idx) = i16::try_from(abs_dc)
-                    {
-                        return Some(dc_idx);
-                    }
-                }
-            }
-        } else {
-            let map = self.proxy_map_v6.read().await;
-            for (dc, addrs) in map.iter() {
-                if addrs
-                    .iter()
-                    .any(|(ip, port)| SocketAddr::new(*ip, *port) == addr)
-                {
-                    let abs_dc = dc.abs();
-                    if abs_dc > 0
-                        && let Ok(dc_idx) = i16::try_from(abs_dc)
-                    {
-                        return Some(dc_idx);
-                    }
-                }
-            }
-        }
-        None
+        i16::try_from(self.resolve_dc_for_endpoint(addr).await).ok()
     }
 
     fn direct_bind_ip_for_stun(
@@ -166,10 +135,15 @@ impl MePool {
     pub(crate) async fn connect_tcp(
         &self,
         addr: SocketAddr,
+        dc_idx_override: Option<i16>,
     ) -> Result<(TcpStream, f64, Option<UpstreamEgressInfo>)> {
         let start = Instant::now();
         let (stream, upstream_egress) = if let Some(upstream) = &self.upstream {
-            let dc_idx = self.resolve_dc_idx_for_endpoint(addr).await;
+            let dc_idx = if let Some(dc_idx) = dc_idx_override {
+                Some(dc_idx)
+            } else {
+                self.resolve_dc_idx_for_endpoint(addr).await
+            };
             let (stream, egress) = upstream.connect_with_details(addr, dc_idx, None).await?;
             (stream, Some(egress))
         } else {
@@ -387,9 +361,11 @@ impl MePool {
             socks_bound_addr.map(|value| value.ip()),
             client_port_source,
         );
-        let mut kdf_fingerprint_guard = self.kdf_material_fingerprint.lock().await;
-        if let Some((prev_fingerprint, prev_client_port)) =
+        let previous_kdf_fingerprint = {
+            let kdf_fingerprint_guard = self.kdf_material_fingerprint.read().await;
             kdf_fingerprint_guard.get(&peer_addr_nat).copied()
+        };
+        if let Some((prev_fingerprint, prev_client_port)) = previous_kdf_fingerprint
         {
             if prev_fingerprint != kdf_fingerprint {
                 self.stats.increment_me_kdf_drift_total();
@@ -416,6 +392,9 @@ impl MePool {
                 );
             }
         }
+        // Keep fingerprint updates eventually consistent for diagnostics while avoiding
+        // serializing all concurrent handshakes on a single async mutex.
+        let mut kdf_fingerprint_guard = self.kdf_material_fingerprint.write().await;
         kdf_fingerprint_guard.insert(peer_addr_nat, (kdf_fingerprint, client_port_for_kdf));
         drop(kdf_fingerprint_guard);
 

src/transport/middle_proxy/health.rs

@@ -13,7 +13,6 @@ use crate::network::IpFamily;
 
 use super::MePool;
 
-const HEALTH_INTERVAL_SECS: u64 = 1;
 const JITTER_FRAC_NUM: u64 = 2; // jitter up to 50% of backoff
 #[allow(dead_code)]
 const MAX_CONCURRENT_PER_DC_DEFAULT: usize = 1;
@@ -22,6 +21,34 @@ const IDLE_REFRESH_TRIGGER_BASE_SECS: u64 = 45;
 const IDLE_REFRESH_TRIGGER_JITTER_SECS: u64 = 5;
 const IDLE_REFRESH_RETRY_SECS: u64 = 8;
 const IDLE_REFRESH_SUCCESS_GUARD_SECS: u64 = 5;
+const HEALTH_RECONNECT_BUDGET_PER_CORE: usize = 2;
+const HEALTH_RECONNECT_BUDGET_PER_DC: usize = 1;
+const HEALTH_RECONNECT_BUDGET_MIN: usize = 4;
+const HEALTH_RECONNECT_BUDGET_MAX: usize = 128;
+
+#[derive(Debug, Clone)]
+struct DcFloorPlanEntry {
+    dc: i32,
+    endpoints: Vec<SocketAddr>,
+    alive: usize,
+    min_required: usize,
+    target_required: usize,
+    max_required: usize,
+    has_bound_clients: bool,
+    floor_capped: bool,
+}
+
+#[derive(Debug, Clone)]
+struct FamilyFloorPlan {
+    by_dc: HashMap<i32, DcFloorPlanEntry>,
+    active_cap_configured_total: usize,
+    active_cap_effective_total: usize,
+    warm_cap_configured_total: usize,
+    warm_cap_effective_total: usize,
+    active_writers_current: usize,
+    warm_writers_current: usize,
+    target_writers_total: usize,
+}
 
 pub async fn me_health_monitor(pool: Arc<MePool>, rng: Arc<SecureRandom>, _min_connections: usize) {
     let mut backoff: HashMap<(i32, IpFamily), u64> = HashMap::new();
@@ -34,10 +61,18 @@ pub async fn me_health_monitor(pool: Arc<MePool>, rng: Arc<SecureRandom>, _min_c
     let mut idle_refresh_next_attempt: HashMap<(i32, IpFamily), Instant> = HashMap::new();
     let mut adaptive_idle_since: HashMap<(i32, IpFamily), Instant> = HashMap::new();
     let mut adaptive_recover_until: HashMap<(i32, IpFamily), Instant> = HashMap::new();
+    let mut floor_warn_next_allowed: HashMap<(i32, IpFamily), Instant> = HashMap::new();
+    let mut degraded_interval = true;
     loop {
-        tokio::time::sleep(Duration::from_secs(HEALTH_INTERVAL_SECS)).await;
+        let interval = if degraded_interval {
+            pool.health_interval_unhealthy()
+        } else {
+            pool.health_interval_healthy()
+        };
+        tokio::time::sleep(interval).await;
         pool.prune_closed_writers().await;
-        check_family(
+        reap_draining_writers(&pool).await;
+        let v4_degraded = check_family(
             IpFamily::V4,
             &pool,
             &rng,
@@ -51,9 +86,10 @@ pub async fn me_health_monitor(pool: Arc<MePool>, rng: Arc<SecureRandom>, _min_c
             &mut idle_refresh_next_attempt,
             &mut adaptive_idle_since,
             &mut adaptive_recover_until,
+            &mut floor_warn_next_allowed,
         )
         .await;
-        check_family(
+        let v6_degraded = check_family(
             IpFamily::V6,
             &pool,
             &rng,
@@ -67,8 +103,32 @@ pub async fn me_health_monitor(pool: Arc<MePool>, rng: Arc<SecureRandom>, _min_c
             &mut idle_refresh_next_attempt,
             &mut adaptive_idle_since,
             &mut adaptive_recover_until,
+            &mut floor_warn_next_allowed,
         )
         .await;
+        degraded_interval = v4_degraded || v6_degraded;
+    }
+}
+
+async fn reap_draining_writers(pool: &Arc<MePool>) {
+    let now_epoch_secs = MePool::now_epoch_secs();
+    let writers = pool.writers.read().await.clone();
+    for writer in writers {
+        if !writer.draining.load(std::sync::atomic::Ordering::Relaxed) {
+            continue;
+        }
+        if pool.registry.is_writer_empty(writer.id).await {
+            pool.remove_writer_and_close_clients(writer.id).await;
+            continue;
+        }
+        let deadline_epoch_secs = writer
+            .drain_deadline_epoch_secs
+            .load(std::sync::atomic::Ordering::Relaxed);
+        if deadline_epoch_secs != 0 && now_epoch_secs >= deadline_epoch_secs {
+            warn!(writer_id = writer.id, "Drain timeout, force-closing");
+            pool.stats.increment_pool_force_close_total();
+            pool.remove_writer_and_close_clients(writer.id).await;
+        }
     }
 }
 
@@ -86,71 +146,107 @@ async fn check_family(
     idle_refresh_next_attempt: &mut HashMap<(i32, IpFamily), Instant>,
     adaptive_idle_since: &mut HashMap<(i32, IpFamily), Instant>,
     adaptive_recover_until: &mut HashMap<(i32, IpFamily), Instant>,
-) {
+    floor_warn_next_allowed: &mut HashMap<(i32, IpFamily), Instant>,
+) -> bool {
     let enabled = match family {
         IpFamily::V4 => pool.decision.ipv4_me,
         IpFamily::V6 => pool.decision.ipv6_me,
     };
     if !enabled {
-        return;
+        return false;
     }
 
-    let map = match family {
-        IpFamily::V4 => pool.proxy_map_v4.read().await.clone(),
-        IpFamily::V6 => pool.proxy_map_v6.read().await.clone(),
-    };
+    let mut family_degraded = false;
 
     let mut dc_endpoints = HashMap::<i32, Vec<SocketAddr>>::new();
-    for (dc, addrs) in map {
-        let entry = dc_endpoints.entry(dc.abs()).or_default();
-        for (ip, port) in addrs {
+    let map_guard = match family {
+        IpFamily::V4 => pool.proxy_map_v4.read().await,
+        IpFamily::V6 => pool.proxy_map_v6.read().await,
+    };
+    for (dc, addrs) in map_guard.iter() {
+        let entry = dc_endpoints.entry(*dc).or_default();
+        for (ip, port) in addrs.iter().copied() {
             entry.push(SocketAddr::new(ip, port));
         }
     }
+    drop(map_guard);
     for endpoints in dc_endpoints.values_mut() {
         endpoints.sort_unstable();
         endpoints.dedup();
     }
+    let mut reconnect_budget = health_reconnect_budget(pool, dc_endpoints.len());
 
     if pool.floor_mode() == MeFloorMode::Static {
         adaptive_idle_since.clear();
         adaptive_recover_until.clear();
     }
 
-    let mut live_addr_counts = HashMap::<SocketAddr, usize>::new();
-    let mut live_writer_ids_by_addr = HashMap::<SocketAddr, Vec<u64>>::new();
+    let mut live_addr_counts = HashMap::<(i32, SocketAddr), usize>::new();
+    let mut live_writer_ids_by_addr = HashMap::<(i32, SocketAddr), Vec<u64>>::new();
     for writer in pool.writers.read().await.iter().filter(|w| {
         !w.draining.load(std::sync::atomic::Ordering::Relaxed)
     }) {
-        *live_addr_counts.entry(writer.addr).or_insert(0) += 1;
+        if !matches!(
+            super::pool::WriterContour::from_u8(
+                writer.contour.load(std::sync::atomic::Ordering::Relaxed),
+            ),
+            super::pool::WriterContour::Active
+        ) {
+            continue;
+        }
+        let key = (writer.writer_dc, writer.addr);
+        *live_addr_counts.entry(key).or_insert(0) += 1;
         live_writer_ids_by_addr
-            .entry(writer.addr)
+            .entry(key)
             .or_default()
             .push(writer.id);
     }
     let writer_idle_since = pool.registry.writer_idle_since_snapshot().await;
+    let bound_clients_by_writer = pool
+        .registry
+        .writer_activity_snapshot()
+        .await
+        .bound_clients_by_writer;
+    let floor_plan = build_family_floor_plan(
+        pool,
+        family,
+        &dc_endpoints,
+        &live_addr_counts,
+        &live_writer_ids_by_addr,
+        &bound_clients_by_writer,
+        adaptive_idle_since,
+        adaptive_recover_until,
+    )
+    .await;
+    pool.set_adaptive_floor_runtime_caps(
+        floor_plan.active_cap_configured_total,
+        floor_plan.active_cap_effective_total,
+        floor_plan.warm_cap_configured_total,
+        floor_plan.warm_cap_effective_total,
+        floor_plan.target_writers_total,
+        floor_plan.active_writers_current,
+        floor_plan.warm_writers_current,
+    );
 
     for (dc, endpoints) in dc_endpoints {
         if endpoints.is_empty() {
             continue;
         }
         let key = (dc, family);
-        let reduce_for_idle = should_reduce_floor_for_idle(
-            pool,
-            key,
-            &endpoints,
-            &live_writer_ids_by_addr,
-            adaptive_idle_since,
-            adaptive_recover_until,
-        )
-        .await;
-        let required = pool.required_writers_for_dc_with_floor_mode(endpoints.len(), reduce_for_idle);
+        let required = floor_plan
+            .by_dc
+            .get(&dc)
+            .map(|entry| entry.target_required)
+            .unwrap_or_else(|| {
+                pool.required_writers_for_dc_with_floor_mode(endpoints.len(), false)
+            });
         let alive = endpoints
             .iter()
-            .map(|addr| *live_addr_counts.get(addr).unwrap_or(&0))
+            .map(|addr| *live_addr_counts.get(&(dc, *addr)).unwrap_or(&0))
             .sum::<usize>();
 
         if endpoints.len() == 1 && pool.single_endpoint_outage_mode_enabled() && alive == 0 {
+            family_degraded = true;
             if single_endpoint_outage.insert(key) {
                 pool.stats.increment_me_single_endpoint_outage_enter_total();
                 warn!(
@@ -170,6 +266,7 @@ async fn check_family(
                 required,
                 outage_backoff,
                 outage_next_attempt,
+                &mut reconnect_budget,
             )
             .await;
             continue;
@@ -205,6 +302,7 @@ async fn check_family(
                 required,
                 &live_writer_ids_by_addr,
                 &writer_idle_since,
+                &bound_clients_by_writer,
                 idle_refresh_next_attempt,
             )
             .await;
@@ -218,14 +316,34 @@ async fn check_family(
                 alive,
                 required,
                 &live_writer_ids_by_addr,
+                &bound_clients_by_writer,
                 shadow_rotate_deadline,
             )
             .await;
             continue;
         }
         let missing = required - alive;
+        family_degraded = true;
 
         let now = Instant::now();
+        if reconnect_budget == 0 {
+            let base_ms = pool.me_reconnect_backoff_base.as_millis() as u64;
+            let next_ms = (*backoff.get(&key).unwrap_or(&base_ms)).max(base_ms);
+            let jitter = next_ms / JITTER_FRAC_NUM;
+            let wait = Duration::from_millis(next_ms)
+                + Duration::from_millis(rand::rng().random_range(0..=jitter.max(1)));
+            next_attempt.insert(key, now + wait);
+            debug!(
+                dc = %dc,
+                ?family,
+                alive,
+                required,
+                endpoint_count = endpoints.len(),
+                reconnect_budget,
+                "Skipping reconnect due to per-tick health reconnect budget"
+            );
+            continue;
+        }
         if let Some(ts) = next_attempt.get(&key)
             && now < *ts
         {
@@ -236,7 +354,10 @@ async fn check_family(
         if *inflight.get(&key).unwrap_or(&0) >= max_concurrent {
             continue;
         }
-        if pool.has_refill_inflight_for_endpoints(&endpoints).await {
+        if pool
+            .has_refill_inflight_for_dc_key(super::pool::RefillDcKey { dc, family })
+            .await
+        {
             debug!(
                 dc = %dc,
                 ?family,
@@ -251,9 +372,44 @@ async fn check_family(
 
         let mut restored = 0usize;
         for _ in 0..missing {
+            if reconnect_budget == 0 {
+                break;
+            }
+            reconnect_budget = reconnect_budget.saturating_sub(1);
+            if pool.active_contour_writer_count_total().await
+                >= floor_plan.active_cap_effective_total
+            {
+                let swapped = maybe_swap_idle_writer_for_cap(
+                    pool,
+                    rng,
+                    dc,
+                    family,
+                    &endpoints,
+                    &live_writer_ids_by_addr,
+                    &writer_idle_since,
+                    &bound_clients_by_writer,
+                )
+                .await;
+                if swapped {
+                    pool.stats.increment_me_floor_swap_idle_total();
+                    restored += 1;
+                    continue;
+                }
+                pool.stats.increment_me_floor_cap_block_total();
+                pool.stats.increment_me_floor_swap_idle_failed_total();
+                debug!(
+                    dc = %dc,
+                    ?family,
+                    alive,
+                    required,
+                    active_cap_effective_total = floor_plan.active_cap_effective_total,
+                    "Adaptive floor cap reached, reconnect attempt blocked"
+                );
+                break;
+            }
             let res = tokio::time::timeout(
                 pool.me_one_timeout,
-                pool.connect_endpoints_round_robin(&endpoints, rng.as_ref()),
+                pool.connect_endpoints_round_robin(dc, &endpoints, rng.as_ref()),
             )
             .await;
             match res {
@@ -295,20 +451,373 @@ async fn check_family(
             let wait = Duration::from_millis(next_ms)
                 + Duration::from_millis(rand::rng().random_range(0..=jitter.max(1)));
             next_attempt.insert(key, now + wait);
-            warn!(
-                dc = %dc,
-                ?family,
-                alive = now_alive,
-                required,
-                endpoint_count = endpoints.len(),
-                backoff_ms = next_ms,
-                "DC writer floor is below required level, scheduled reconnect"
-            );
+            if pool.is_runtime_ready() {
+                let warn_cooldown = pool.warn_rate_limit_duration();
+                if should_emit_rate_limited_warn(
+                    floor_warn_next_allowed,
+                    key,
+                    now,
+                    warn_cooldown,
+                ) {
+                    warn!(
+                        dc = %dc,
+                        ?family,
+                        alive = now_alive,
+                        required,
+                        endpoint_count = endpoints.len(),
+                        backoff_ms = next_ms,
+                        "DC writer floor is below required level, scheduled reconnect"
+                    );
+                }
+            } else {
+                info!(
+                    dc = %dc,
+                    ?family,
+                    alive = now_alive,
+                    required,
+                    endpoint_count = endpoints.len(),
+                    backoff_ms = next_ms,
+                    "DC writer floor is below required level during startup, scheduled reconnect"
+                );
+            }
         }
         if let Some(v) = inflight.get_mut(&key) {
             *v = v.saturating_sub(1);
         }
     }
+
+    family_degraded
+}
+
+fn health_reconnect_budget(pool: &Arc<MePool>, dc_groups: usize) -> usize {
+    let cpu_cores = pool.adaptive_floor_effective_cpu_cores().max(1);
+    let by_cpu = cpu_cores.saturating_mul(HEALTH_RECONNECT_BUDGET_PER_CORE);
+    let by_dc = dc_groups.saturating_mul(HEALTH_RECONNECT_BUDGET_PER_DC);
+    by_cpu
+        .saturating_add(by_dc)
+        .clamp(HEALTH_RECONNECT_BUDGET_MIN, HEALTH_RECONNECT_BUDGET_MAX)
+}
+
+fn should_emit_rate_limited_warn(
+    next_allowed: &mut HashMap<(i32, IpFamily), Instant>,
+    key: (i32, IpFamily),
+    now: Instant,
+    cooldown: Duration,
+) -> bool {
+    let Some(ready_at) = next_allowed.get(&key).copied() else {
+        next_allowed.insert(key, now + cooldown);
+        return true;
+    };
+    if now >= ready_at {
+        next_allowed.insert(key, now + cooldown);
+        return true;
+    }
+    false
+}
+
+fn adaptive_floor_class_min(
+    pool: &Arc<MePool>,
+    endpoint_count: usize,
+    base_required: usize,
+) -> usize {
+    if endpoint_count <= 1 {
+        let min_single = (pool
+            .me_adaptive_floor_min_writers_single_endpoint
+            .load(std::sync::atomic::Ordering::Relaxed) as usize)
+            .max(1);
+        min_single.min(base_required.max(1))
+    } else {
+        pool.adaptive_floor_min_writers_multi_endpoint()
+            .min(base_required.max(1))
+    }
+}
+
+fn adaptive_floor_class_max(
+    pool: &Arc<MePool>,
+    endpoint_count: usize,
+    base_required: usize,
+    cpu_cores: usize,
+) -> usize {
+    let extra_per_core = if endpoint_count <= 1 {
+        pool.adaptive_floor_max_extra_single_per_core()
+    } else {
+        pool.adaptive_floor_max_extra_multi_per_core()
+    };
+    base_required.saturating_add(cpu_cores.saturating_mul(extra_per_core))
+}
+
+fn list_writer_ids_for_endpoints(
+    dc: i32,
+    endpoints: &[SocketAddr],
+    live_writer_ids_by_addr: &HashMap<(i32, SocketAddr), Vec<u64>>,
+) -> Vec<u64> {
+    let mut out = Vec::<u64>::new();
+    for endpoint in endpoints {
+        if let Some(ids) = live_writer_ids_by_addr.get(&(dc, *endpoint)) {
+            out.extend(ids.iter().copied());
+        }
+    }
+    out
+}
+
+async fn build_family_floor_plan(
+    pool: &Arc<MePool>,
+    family: IpFamily,
+    dc_endpoints: &HashMap<i32, Vec<SocketAddr>>,
+    live_addr_counts: &HashMap<(i32, SocketAddr), usize>,
+    live_writer_ids_by_addr: &HashMap<(i32, SocketAddr), Vec<u64>>,
+    bound_clients_by_writer: &HashMap<u64, usize>,
+    adaptive_idle_since: &mut HashMap<(i32, IpFamily), Instant>,
+    adaptive_recover_until: &mut HashMap<(i32, IpFamily), Instant>,
+) -> FamilyFloorPlan {
+    let mut entries = Vec::<DcFloorPlanEntry>::new();
+    let mut by_dc = HashMap::<i32, DcFloorPlanEntry>::new();
+    let mut family_active_total = 0usize;
+
+    let floor_mode = pool.floor_mode();
+    let is_adaptive = floor_mode == MeFloorMode::Adaptive;
+    let cpu_cores = pool.adaptive_floor_effective_cpu_cores().max(1);
+    let (active_writers_current, warm_writers_current, _) =
+        pool.non_draining_writer_counts_by_contour().await;
+
+    for (dc, endpoints) in dc_endpoints {
+        if endpoints.is_empty() {
+            continue;
+        }
+        let key = (*dc, family);
+        let reduce_for_idle = should_reduce_floor_for_idle(
+            pool,
+            key,
+            *dc,
+            endpoints,
+            live_writer_ids_by_addr,
+            bound_clients_by_writer,
+            adaptive_idle_since,
+            adaptive_recover_until,
+        )
+        .await;
+        let base_required = pool.required_writers_for_dc(endpoints.len()).max(1);
+        let min_required = if is_adaptive {
+            adaptive_floor_class_min(pool, endpoints.len(), base_required)
+        } else {
+            base_required
+        };
+        let mut max_required = if is_adaptive {
+            adaptive_floor_class_max(pool, endpoints.len(), base_required, cpu_cores)
+        } else {
+            base_required
+        };
+        if max_required < min_required {
+            max_required = min_required;
+        }
+        let desired_raw = if is_adaptive && reduce_for_idle {
+            min_required
+        } else {
+            base_required
+        };
+        let target_required = desired_raw.clamp(min_required, max_required);
+        let alive = endpoints
+            .iter()
+            .map(|endpoint| live_addr_counts.get(&(*dc, *endpoint)).copied().unwrap_or(0))
+            .sum::<usize>();
+        family_active_total = family_active_total.saturating_add(alive);
+        let writer_ids = list_writer_ids_for_endpoints(*dc, endpoints, live_writer_ids_by_addr);
+        let has_bound_clients = has_bound_clients_on_endpoint(&writer_ids, bound_clients_by_writer);
+
+        entries.push(DcFloorPlanEntry {
+            dc: *dc,
+            endpoints: endpoints.clone(),
+            alive,
+            min_required,
+            target_required,
+            max_required,
+            has_bound_clients,
+            floor_capped: false,
+        });
+    }
+
+    if entries.is_empty() {
+        let active_cap_configured_total = pool.adaptive_floor_active_cap_configured_total();
+        let warm_cap_configured_total = pool.adaptive_floor_warm_cap_configured_total();
+        return FamilyFloorPlan {
+            by_dc,
+            active_cap_configured_total,
+            active_cap_effective_total: active_cap_configured_total,
+            warm_cap_configured_total,
+            warm_cap_effective_total: warm_cap_configured_total,
+            active_writers_current,
+            warm_writers_current,
+            target_writers_total: 0,
+        };
+    }
+
+    if !is_adaptive {
+        let target_total = entries
+            .iter()
+            .map(|entry| entry.target_required)
+            .sum::<usize>();
+        let active_cap_configured_total = pool.adaptive_floor_active_cap_configured_total();
+        let warm_cap_configured_total = pool.adaptive_floor_warm_cap_configured_total();
+        for entry in entries {
+            by_dc.insert(entry.dc, entry);
+        }
+        return FamilyFloorPlan {
+            by_dc,
+            active_cap_configured_total,
+            active_cap_effective_total: active_cap_configured_total.max(target_total),
+            warm_cap_configured_total,
+            warm_cap_effective_total: warm_cap_configured_total,
+            active_writers_current,
+            warm_writers_current,
+            target_writers_total: target_total,
+        };
+    }
+
+    let active_cap_configured_total = pool.adaptive_floor_active_cap_configured_total();
+    let warm_cap_configured_total = pool.adaptive_floor_warm_cap_configured_total();
+    let other_active = active_writers_current.saturating_sub(family_active_total);
+    let min_sum = entries
+        .iter()
+        .map(|entry| entry.min_required)
+        .sum::<usize>();
+    let mut target_sum = entries
+        .iter()
+        .map(|entry| entry.target_required)
+        .sum::<usize>();
+    let family_cap = active_cap_configured_total
+        .saturating_sub(other_active)
+        .max(min_sum);
+    if target_sum > family_cap {
+        entries.sort_by_key(|entry| {
+            (
+                entry.has_bound_clients,
+                std::cmp::Reverse(entry.target_required.saturating_sub(entry.min_required)),
+                std::cmp::Reverse(entry.alive),
+                entry.dc.abs(),
+                entry.dc,
+                entry.endpoints.len(),
+                entry.max_required,
+            )
+        });
+        let mut changed = true;
+        while target_sum > family_cap && changed {
+            changed = false;
+            for entry in &mut entries {
+                if target_sum <= family_cap {
+                    break;
+                }
+                if entry.target_required > entry.min_required {
+                    entry.target_required -= 1;
+                    entry.floor_capped = true;
+                    target_sum -= 1;
+                    changed = true;
+                }
+            }
+        }
+    }
+
+    for entry in entries {
+        by_dc.insert(entry.dc, entry);
+    }
+    let active_cap_effective_total =
+        active_cap_configured_total.max(other_active.saturating_add(min_sum));
+    let target_writers_total = other_active.saturating_add(target_sum);
+    FamilyFloorPlan {
+        by_dc,
+        active_cap_configured_total,
+        active_cap_effective_total,
+        warm_cap_configured_total,
+        warm_cap_effective_total: warm_cap_configured_total,
+        active_writers_current,
+        warm_writers_current,
+        target_writers_total,
+    }
+}
+
+async fn maybe_swap_idle_writer_for_cap(
+    pool: &Arc<MePool>,
+    rng: &Arc<SecureRandom>,
+    dc: i32,
+    family: IpFamily,
+    endpoints: &[SocketAddr],
+    live_writer_ids_by_addr: &HashMap<(i32, SocketAddr), Vec<u64>>,
+    writer_idle_since: &HashMap<u64, u64>,
+    bound_clients_by_writer: &HashMap<u64, usize>,
+) -> bool {
+    let now_epoch_secs = MePool::now_epoch_secs();
+    let mut candidate: Option<(u64, SocketAddr, u64)> = None;
+    for endpoint in endpoints {
+        let Some(writer_ids) = live_writer_ids_by_addr.get(&(dc, *endpoint)) else {
+            continue;
+        };
+        for writer_id in writer_ids {
+            if bound_clients_by_writer.get(writer_id).copied().unwrap_or(0) > 0 {
+                continue;
+            }
+            let Some(idle_since_epoch_secs) = writer_idle_since.get(writer_id).copied() else {
+                continue;
+            };
+            let idle_age_secs = now_epoch_secs.saturating_sub(idle_since_epoch_secs);
+            if candidate
+                .as_ref()
+                .map(|(_, _, age)| idle_age_secs > *age)
+                .unwrap_or(true)
+            {
+                candidate = Some((*writer_id, *endpoint, idle_age_secs));
+            }
+        }
+    }
+
+    let Some((old_writer_id, endpoint, idle_age_secs)) = candidate else {
+        return false;
+    };
+
+    let connected = match tokio::time::timeout(
+        pool.me_one_timeout,
+        pool.connect_one_for_dc(endpoint, dc, rng.as_ref()),
+    )
+    .await
+    {
+        Ok(Ok(())) => true,
+        Ok(Err(error)) => {
+            debug!(
+                dc = %dc,
+                ?family,
+                %endpoint,
+                old_writer_id,
+                idle_age_secs,
+                %error,
+                "Adaptive floor cap swap connect failed"
+            );
+            false
+        }
+        Err(_) => {
+            debug!(
+                dc = %dc,
+                ?family,
+                %endpoint,
+                old_writer_id,
+                idle_age_secs,
+                "Adaptive floor cap swap connect timed out"
+            );
+            false
+        }
+    };
+    if !connected {
+        return false;
+    }
+
+    pool.mark_writer_draining_with_timeout(old_writer_id, pool.force_close_timeout(), false)
+        .await;
+    info!(
+        dc = %dc,
+        ?family,
+        %endpoint,
+        old_writer_id,
+        idle_age_secs,
+        "Adaptive floor cap swap: idle writer rotated"
+    );
+    true
 }
 
 async fn maybe_refresh_idle_writer_for_dc(
@@ -320,8 +829,9 @@ async fn maybe_refresh_idle_writer_for_dc(
     endpoints: &[SocketAddr],
     alive: usize,
     required: usize,
-    live_writer_ids_by_addr: &HashMap<SocketAddr, Vec<u64>>,
+    live_writer_ids_by_addr: &HashMap<(i32, SocketAddr), Vec<u64>>,
     writer_idle_since: &HashMap<u64, u64>,
+    bound_clients_by_writer: &HashMap<u64, usize>,
     idle_refresh_next_attempt: &mut HashMap<(i32, IpFamily), Instant>,
 ) {
     if alive < required {
@@ -338,10 +848,13 @@ async fn maybe_refresh_idle_writer_for_dc(
     let now_epoch_secs = MePool::now_epoch_secs();
     let mut candidate: Option<(u64, SocketAddr, u64, u64)> = None;
     for endpoint in endpoints {
-        let Some(writer_ids) = live_writer_ids_by_addr.get(endpoint) else {
+        let Some(writer_ids) = live_writer_ids_by_addr.get(&(dc, *endpoint)) else {
             continue;
         };
         for writer_id in writer_ids {
+            if bound_clients_by_writer.get(writer_id).copied().unwrap_or(0) > 0 {
+                continue;
+            }
             let Some(idle_since_epoch_secs) = writer_idle_since.get(writer_id).copied() else {
                 continue;
             };
@@ -365,7 +878,12 @@ async fn maybe_refresh_idle_writer_for_dc(
         return;
     };
 
-    let rotate_ok = match tokio::time::timeout(pool.me_one_timeout, pool.connect_one(endpoint, rng.as_ref())).await {
+    let rotate_ok = match tokio::time::timeout(
+        pool.me_one_timeout,
+        pool.connect_one_for_dc(endpoint, dc, rng.as_ref()),
+    )
+    .await
+    {
         Ok(Ok(())) => true,
         Ok(Err(error)) => {
             debug!(
@@ -421,24 +939,22 @@ async fn maybe_refresh_idle_writer_for_dc(
 async fn should_reduce_floor_for_idle(
     pool: &Arc<MePool>,
     key: (i32, IpFamily),
+    dc: i32,
     endpoints: &[SocketAddr],
-    live_writer_ids_by_addr: &HashMap<SocketAddr, Vec<u64>>,
+    live_writer_ids_by_addr: &HashMap<(i32, SocketAddr), Vec<u64>>,
+    bound_clients_by_writer: &HashMap<u64, usize>,
     adaptive_idle_since: &mut HashMap<(i32, IpFamily), Instant>,
     adaptive_recover_until: &mut HashMap<(i32, IpFamily), Instant>,
 ) -> bool {
-    if endpoints.len() != 1 || pool.floor_mode() != MeFloorMode::Adaptive {
+    if pool.floor_mode() != MeFloorMode::Adaptive {
         adaptive_idle_since.remove(&key);
         adaptive_recover_until.remove(&key);
         return false;
     }
 
     let now = Instant::now();
-    let endpoint = endpoints[0];
-    let writer_ids = live_writer_ids_by_addr
-        .get(&endpoint)
-        .map(Vec::as_slice)
-        .unwrap_or(&[]);
-    let has_bound_clients = has_bound_clients_on_endpoint(pool, writer_ids).await;
+    let writer_ids = list_writer_ids_for_endpoints(dc, endpoints, live_writer_ids_by_addr);
+    let has_bound_clients = has_bound_clients_on_endpoint(&writer_ids, bound_clients_by_writer);
     if has_bound_clients {
         adaptive_idle_since.remove(&key);
         adaptive_recover_until.insert(key, now + pool.adaptive_floor_recover_grace_duration());
@@ -457,13 +973,13 @@ async fn should_reduce_floor_for_idle(
     now.saturating_duration_since(*idle_since) >= pool.adaptive_floor_idle_duration()
 }
 
-async fn has_bound_clients_on_endpoint(pool: &Arc<MePool>, writer_ids: &[u64]) -> bool {
-    for writer_id in writer_ids {
-        if !pool.registry.is_writer_empty(*writer_id).await {
-            return true;
-        }
-    }
-    false
+fn has_bound_clients_on_endpoint(
+    writer_ids: &[u64],
+    bound_clients_by_writer: &HashMap<u64, usize>,
+) -> bool {
+    writer_ids
+        .iter()
+        .any(|writer_id| bound_clients_by_writer.get(writer_id).copied().unwrap_or(0) > 0)
 }
 
 async fn recover_single_endpoint_outage(
@@ -474,6 +990,7 @@ async fn recover_single_endpoint_outage(
     required: usize,
     outage_backoff: &mut HashMap<(i32, IpFamily), u64>,
     outage_next_attempt: &mut HashMap<(i32, IpFamily), Instant>,
+    reconnect_budget: &mut usize,
 ) {
     let now = Instant::now();
     if let Some(ts) = outage_next_attempt.get(&key)
@@ -483,6 +1000,18 @@ async fn recover_single_endpoint_outage(
     }
 
     let (min_backoff_ms, max_backoff_ms) = pool.single_endpoint_outage_backoff_bounds_ms();
+    if *reconnect_budget == 0 {
+        outage_next_attempt.insert(key, now + Duration::from_millis(min_backoff_ms.max(250)));
+        debug!(
+            dc = %key.0,
+            family = ?key.1,
+            %endpoint,
+            required,
+            "Single-endpoint outage reconnect deferred by health reconnect budget"
+        );
+        return;
+    }
+    *reconnect_budget = (*reconnect_budget).saturating_sub(1);
     pool.stats
         .increment_me_single_endpoint_outage_reconnect_attempt_total();
 
@@ -490,7 +1019,12 @@ async fn recover_single_endpoint_outage(
     let attempt_ok = if bypass_quarantine {
         pool.stats
             .increment_me_single_endpoint_quarantine_bypass_total();
-        match tokio::time::timeout(pool.me_one_timeout, pool.connect_one(endpoint, rng.as_ref())).await {
+        match tokio::time::timeout(
+            pool.me_one_timeout,
+            pool.connect_one_for_dc(endpoint, key.0, rng.as_ref()),
+        )
+        .await
+        {
             Ok(Ok(())) => true,
             Ok(Err(e)) => {
                 debug!(
@@ -516,7 +1050,7 @@ async fn recover_single_endpoint_outage(
         let one_endpoint = [endpoint];
         match tokio::time::timeout(
             pool.me_one_timeout,
-            pool.connect_endpoints_round_robin(&one_endpoint, rng.as_ref()),
+            pool.connect_endpoints_round_robin(key.0, &one_endpoint, rng.as_ref()),
         )
         .await
         {
@@ -580,7 +1114,8 @@ async fn maybe_rotate_single_endpoint_shadow(
     endpoints: &[SocketAddr],
     alive: usize,
     required: usize,
-    live_writer_ids_by_addr: &HashMap<SocketAddr, Vec<u64>>,
+    live_writer_ids_by_addr: &HashMap<(i32, SocketAddr), Vec<u64>>,
+    bound_clients_by_writer: &HashMap<u64, usize>,
     shadow_rotate_deadline: &mut HashMap<(i32, IpFamily), Instant>,
 ) {
     if endpoints.len() != 1 || alive < required {
@@ -612,14 +1147,14 @@ async fn maybe_rotate_single_endpoint_shadow(
         return;
     }
 
-    let Some(writer_ids) = live_writer_ids_by_addr.get(&endpoint) else {
+    let Some(writer_ids) = live_writer_ids_by_addr.get(&(dc, endpoint)) else {
         shadow_rotate_deadline.insert(key, now + Duration::from_secs(SHADOW_ROTATE_RETRY_SECS));
         return;
     };
 
     let mut candidate_writer_id = None;
     for writer_id in writer_ids {
-        if pool.registry.is_writer_empty(*writer_id).await {
+        if bound_clients_by_writer.get(writer_id).copied().unwrap_or(0) == 0 {
             candidate_writer_id = Some(*writer_id);
             break;
         }
@@ -638,7 +1173,12 @@ async fn maybe_rotate_single_endpoint_shadow(
         return;
     };
 
-    let rotate_ok = match tokio::time::timeout(pool.me_one_timeout, pool.connect_one(endpoint, rng.as_ref())).await {
+    let rotate_ok = match tokio::time::timeout(
+        pool.me_one_timeout,
+        pool.connect_one_for_dc(endpoint, dc, rng.as_ref()),
+    )
+    .await
+    {
         Ok(Ok(())) => true,
         Ok(Err(e)) => {
             debug!(

src/transport/middle_proxy/mod.rs

@@ -10,6 +10,7 @@ mod pool_init;
 mod pool_nat;
 mod pool_refill;
 mod pool_reinit;
+mod pool_runtime_api;
 mod pool_writer;
 mod ping;
 mod reader;
@@ -30,7 +31,11 @@ pub use pool::MePool;
 pub use pool_nat::{stun_probe, detect_public_ip};
 pub use registry::ConnRegistry;
 pub use secret::fetch_proxy_secret;
-pub use config_updater::{fetch_proxy_config, me_config_updater};
+#[allow(unused_imports)]
+pub use config_updater::{
+    ProxyConfigData, fetch_proxy_config, fetch_proxy_config_with_raw, load_proxy_config_cache,
+    me_config_updater, save_proxy_config_cache,
+};
 pub use rotation::{MeReinitTrigger, me_reinit_scheduler, me_rotation_task};
 pub use wire::proto_flags_for_tag;
 

src/transport/middle_proxy/ping.rs

@@ -331,7 +331,7 @@ pub async fn run_me_ping(pool: &Arc<MePool>, rng: &SecureRandom) -> Vec<MePingRe
             let mut error = None;
             let mut route = None;
 
-            match pool.connect_tcp(addr).await {
+            match pool.connect_tcp(addr, None).await {
                 Ok((stream, conn_rtt, upstream_egress)) => {
                     connect_ms = Some(conn_rtt);
                     route = route_from_egress(upstream_egress);

src/transport/middle_proxy/pool.rs

@@ -7,7 +7,7 @@ use std::time::{Duration, Instant, SystemTime, UNIX_EPOCH};
 use tokio::sync::{Mutex, Notify, RwLock, mpsc};
 use tokio_util::sync::CancellationToken;
 
-use crate::config::{MeBindStaleMode, MeFloorMode, MeSocksKdfPolicy};
+use crate::config::{MeBindStaleMode, MeFloorMode, MeRouteNoWriterMode, MeSocksKdfPolicy};
 use crate::crypto::SecureRandom;
 use crate::network::IpFamily;
 use crate::network::probe::NetworkDecision;
@@ -22,10 +22,17 @@ pub(super) struct RefillDcKey {
     pub family: IpFamily,
 }
 
+#[derive(Debug, Clone, Copy, PartialEq, Eq, Hash)]
+pub(super) struct RefillEndpointKey {
+    pub dc: i32,
+    pub addr: SocketAddr,
+}
+
 #[derive(Clone)]
 pub struct MeWriter {
     pub id: u64,
     pub addr: SocketAddr,
+    pub writer_dc: i32,
     pub generation: u64,
     pub contour: Arc<AtomicU8>,
     pub created_at: Instant,
@@ -34,6 +41,7 @@ pub struct MeWriter {
     pub degraded: Arc<AtomicBool>,
     pub draining: Arc<AtomicBool>,
     pub draining_started_at_epoch_secs: Arc<AtomicU64>,
+    pub drain_deadline_epoch_secs: Arc<AtomicU64>,
     pub allow_drain_fallback: Arc<AtomicBool>,
 }
 
@@ -95,6 +103,7 @@ pub struct MePool {
     pub(super) me_keepalive_jitter: Duration,
     pub(super) me_keepalive_payload_random: bool,
     pub(super) rpc_proxy_req_every_secs: AtomicU64,
+    pub(super) writer_cmd_channel_capacity: usize,
     pub(super) me_warmup_stagger_enabled: bool,
     pub(super) me_warmup_step_delay: Duration,
     pub(super) me_warmup_step_jitter: Duration,
@@ -111,16 +120,40 @@ pub struct MePool {
     pub(super) me_floor_mode: AtomicU8,
     pub(super) me_adaptive_floor_idle_secs: AtomicU64,
     pub(super) me_adaptive_floor_min_writers_single_endpoint: AtomicU8,
+    pub(super) me_adaptive_floor_min_writers_multi_endpoint: AtomicU8,
     pub(super) me_adaptive_floor_recover_grace_secs: AtomicU64,
+    pub(super) me_adaptive_floor_writers_per_core_total: AtomicU32,
+    pub(super) me_adaptive_floor_cpu_cores_override: AtomicU32,
+    pub(super) me_adaptive_floor_max_extra_writers_single_per_core: AtomicU32,
+    pub(super) me_adaptive_floor_max_extra_writers_multi_per_core: AtomicU32,
+    pub(super) me_adaptive_floor_max_active_writers_per_core: AtomicU32,
+    pub(super) me_adaptive_floor_max_warm_writers_per_core: AtomicU32,
+    pub(super) me_adaptive_floor_max_active_writers_global: AtomicU32,
+    pub(super) me_adaptive_floor_max_warm_writers_global: AtomicU32,
+    pub(super) me_adaptive_floor_cpu_cores_detected: AtomicU32,
+    pub(super) me_adaptive_floor_cpu_cores_effective: AtomicU32,
+    pub(super) me_adaptive_floor_global_cap_raw: AtomicU64,
+    pub(super) me_adaptive_floor_global_cap_effective: AtomicU64,
+    pub(super) me_adaptive_floor_target_writers_total: AtomicU64,
+    pub(super) me_adaptive_floor_active_cap_configured: AtomicU64,
+    pub(super) me_adaptive_floor_active_cap_effective: AtomicU64,
+    pub(super) me_adaptive_floor_warm_cap_configured: AtomicU64,
+    pub(super) me_adaptive_floor_warm_cap_effective: AtomicU64,
+    pub(super) me_adaptive_floor_active_writers_current: AtomicU64,
+    pub(super) me_adaptive_floor_warm_writers_current: AtomicU64,
     pub(super) proxy_map_v4: Arc<RwLock<HashMap<i32, Vec<(IpAddr, u16)>>>>,
     pub(super) proxy_map_v6: Arc<RwLock<HashMap<i32, Vec<(IpAddr, u16)>>>>,
+    pub(super) endpoint_dc_map: Arc<RwLock<HashMap<SocketAddr, Option<i32>>>>,
     pub(super) default_dc: AtomicI32,
     pub(super) next_writer_id: AtomicU64,
     pub(super) ping_tracker: Arc<Mutex<HashMap<i64, (std::time::Instant, u64)>>>,
+    pub(super) ping_tracker_last_cleanup_epoch_ms: AtomicU64,
     pub(super) rtt_stats: Arc<Mutex<HashMap<u64, (f64, f64)>>>,
     pub(super) nat_reflection_cache: Arc<Mutex<NatReflectionCache>>,
+    pub(super) nat_reflection_singleflight_v4: Arc<Mutex<()>>,
+    pub(super) nat_reflection_singleflight_v6: Arc<Mutex<()>>,
     pub(super) writer_available: Arc<Notify>,
-    pub(super) refill_inflight: Arc<Mutex<HashSet<SocketAddr>>>,
+    pub(super) refill_inflight: Arc<Mutex<HashSet<RefillEndpointKey>>>,
     pub(super) refill_inflight_dc: Arc<Mutex<HashSet<RefillDcKey>>>,
     pub(super) conn_count: AtomicUsize,
     pub(super) stats: Arc<crate::stats::Stats>,
@@ -132,7 +165,7 @@ pub struct MePool {
     pub(super) pending_hardswap_map_hash: AtomicU64,
     pub(super) hardswap: AtomicBool,
     pub(super) endpoint_quarantine: Arc<Mutex<HashMap<SocketAddr, Instant>>>,
-    pub(super) kdf_material_fingerprint: Arc<Mutex<HashMap<SocketAddr, (u64, u16)>>>,
+    pub(super) kdf_material_fingerprint: Arc<RwLock<HashMap<SocketAddr, (u64, u16)>>>,
     pub(super) me_pool_drain_ttl_secs: AtomicU64,
     pub(super) me_pool_force_close_secs: AtomicU64,
     pub(super) me_pool_min_fresh_ratio_permille: AtomicU32,
@@ -145,7 +178,16 @@ pub struct MePool {
     pub(super) secret_atomic_snapshot: AtomicBool,
     pub(super) me_deterministic_writer_sort: AtomicBool,
     pub(super) me_socks_kdf_policy: AtomicU8,
+    pub(super) me_route_no_writer_mode: AtomicU8,
+    pub(super) me_route_no_writer_wait: Duration,
+    pub(super) me_route_inline_recovery_attempts: u32,
+    pub(super) me_route_inline_recovery_wait: Duration,
+    pub(super) me_health_interval_ms_unhealthy: AtomicU64,
+    pub(super) me_health_interval_ms_healthy: AtomicU64,
+    pub(super) me_warn_rate_limit_ms: AtomicU64,
+    pub(super) runtime_ready: AtomicBool,
     pool_size: usize,
+    pub(super) preferred_endpoints_by_dc: Arc<RwLock<HashMap<i32, Vec<SocketAddr>>>>,
 }
 
 #[derive(Debug, Default)]
@@ -210,7 +252,16 @@ impl MePool {
         me_floor_mode: MeFloorMode,
         me_adaptive_floor_idle_secs: u64,
         me_adaptive_floor_min_writers_single_endpoint: u8,
+        me_adaptive_floor_min_writers_multi_endpoint: u8,
         me_adaptive_floor_recover_grace_secs: u64,
+        me_adaptive_floor_writers_per_core_total: u16,
+        me_adaptive_floor_cpu_cores_override: u16,
+        me_adaptive_floor_max_extra_writers_single_per_core: u16,
+        me_adaptive_floor_max_extra_writers_multi_per_core: u16,
+        me_adaptive_floor_max_active_writers_per_core: u16,
+        me_adaptive_floor_max_warm_writers_per_core: u16,
+        me_adaptive_floor_max_active_writers_global: u32,
+        me_adaptive_floor_max_warm_writers_global: u32,
         hardswap: bool,
         me_pool_drain_ttl_secs: u64,
         me_pool_force_close_secs: u64,
@@ -224,11 +275,25 @@ impl MePool {
         me_secret_atomic_snapshot: bool,
         me_deterministic_writer_sort: bool,
         me_socks_kdf_policy: MeSocksKdfPolicy,
+        me_writer_cmd_channel_capacity: usize,
+        me_route_channel_capacity: usize,
         me_route_backpressure_base_timeout_ms: u64,
         me_route_backpressure_high_timeout_ms: u64,
         me_route_backpressure_high_watermark_pct: u8,
+        me_health_interval_ms_unhealthy: u64,
+        me_health_interval_ms_healthy: u64,
+        me_warn_rate_limit_ms: u64,
+        me_route_no_writer_mode: MeRouteNoWriterMode,
+        me_route_no_writer_wait_ms: u64,
+        me_route_inline_recovery_attempts: u32,
+        me_route_inline_recovery_wait_ms: u64,
     ) -> Arc<Self> {
-        let registry = Arc::new(ConnRegistry::new());
+        let endpoint_dc_map = Self::build_endpoint_dc_map_from_maps(&proxy_map_v4, &proxy_map_v6);
+        let preferred_endpoints_by_dc =
+            Self::build_preferred_endpoints_by_dc(&decision, &proxy_map_v4, &proxy_map_v6);
+        let registry = Arc::new(ConnRegistry::with_route_channel_capacity(
+            me_route_channel_capacity,
+        ));
         registry.update_route_backpressure_policy(
             me_route_backpressure_base_timeout_ms,
             me_route_backpressure_high_timeout_ms,
@@ -275,6 +340,7 @@ impl MePool {
             me_keepalive_jitter: Duration::from_secs(me_keepalive_jitter_secs),
             me_keepalive_payload_random,
             rpc_proxy_req_every_secs: AtomicU64::new(rpc_proxy_req_every_secs),
+            writer_cmd_channel_capacity: me_writer_cmd_channel_capacity.max(1),
             me_warmup_stagger_enabled,
             me_warmup_step_delay: Duration::from_millis(me_warmup_step_delay_ms),
             me_warmup_step_jitter: Duration::from_millis(me_warmup_step_jitter_ms),
@@ -303,17 +369,59 @@ impl MePool {
             me_adaptive_floor_min_writers_single_endpoint: AtomicU8::new(
                 me_adaptive_floor_min_writers_single_endpoint,
             ),
+            me_adaptive_floor_min_writers_multi_endpoint: AtomicU8::new(
+                me_adaptive_floor_min_writers_multi_endpoint,
+            ),
             me_adaptive_floor_recover_grace_secs: AtomicU64::new(
                 me_adaptive_floor_recover_grace_secs,
             ),
+            me_adaptive_floor_writers_per_core_total: AtomicU32::new(
+                me_adaptive_floor_writers_per_core_total as u32,
+            ),
+            me_adaptive_floor_cpu_cores_override: AtomicU32::new(
+                me_adaptive_floor_cpu_cores_override as u32,
+            ),
+            me_adaptive_floor_max_extra_writers_single_per_core: AtomicU32::new(
+                me_adaptive_floor_max_extra_writers_single_per_core as u32,
+            ),
+            me_adaptive_floor_max_extra_writers_multi_per_core: AtomicU32::new(
+                me_adaptive_floor_max_extra_writers_multi_per_core as u32,
+            ),
+            me_adaptive_floor_max_active_writers_per_core: AtomicU32::new(
+                me_adaptive_floor_max_active_writers_per_core as u32,
+            ),
+            me_adaptive_floor_max_warm_writers_per_core: AtomicU32::new(
+                me_adaptive_floor_max_warm_writers_per_core as u32,
+            ),
+            me_adaptive_floor_max_active_writers_global: AtomicU32::new(
+                me_adaptive_floor_max_active_writers_global,
+            ),
+            me_adaptive_floor_max_warm_writers_global: AtomicU32::new(
+                me_adaptive_floor_max_warm_writers_global,
+            ),
+            me_adaptive_floor_cpu_cores_detected: AtomicU32::new(1),
+            me_adaptive_floor_cpu_cores_effective: AtomicU32::new(1),
+            me_adaptive_floor_global_cap_raw: AtomicU64::new(0),
+            me_adaptive_floor_global_cap_effective: AtomicU64::new(0),
+            me_adaptive_floor_target_writers_total: AtomicU64::new(0),
+            me_adaptive_floor_active_cap_configured: AtomicU64::new(0),
+            me_adaptive_floor_active_cap_effective: AtomicU64::new(0),
+            me_adaptive_floor_warm_cap_configured: AtomicU64::new(0),
+            me_adaptive_floor_warm_cap_effective: AtomicU64::new(0),
+            me_adaptive_floor_active_writers_current: AtomicU64::new(0),
+            me_adaptive_floor_warm_writers_current: AtomicU64::new(0),
             pool_size: 2,
             proxy_map_v4: Arc::new(RwLock::new(proxy_map_v4)),
             proxy_map_v6: Arc::new(RwLock::new(proxy_map_v6)),
-            default_dc: AtomicI32::new(default_dc.unwrap_or(0)),
+            endpoint_dc_map: Arc::new(RwLock::new(endpoint_dc_map)),
+            default_dc: AtomicI32::new(default_dc.unwrap_or(2)),
             next_writer_id: AtomicU64::new(1),
             ping_tracker: Arc::new(Mutex::new(HashMap::new())),
+            ping_tracker_last_cleanup_epoch_ms: AtomicU64::new(0),
             rtt_stats: Arc::new(Mutex::new(HashMap::new())),
             nat_reflection_cache: Arc::new(Mutex::new(NatReflectionCache::default())),
+            nat_reflection_singleflight_v4: Arc::new(Mutex::new(())),
+            nat_reflection_singleflight_v6: Arc::new(Mutex::new(())),
             writer_available: Arc::new(Notify::new()),
             refill_inflight: Arc::new(Mutex::new(HashSet::new())),
             refill_inflight_dc: Arc::new(Mutex::new(HashSet::new())),
@@ -326,7 +434,7 @@ impl MePool {
             pending_hardswap_map_hash: AtomicU64::new(0),
             hardswap: AtomicBool::new(hardswap),
             endpoint_quarantine: Arc::new(Mutex::new(HashMap::new())),
-            kdf_material_fingerprint: Arc::new(Mutex::new(HashMap::new())),
+            kdf_material_fingerprint: Arc::new(RwLock::new(HashMap::new())),
             me_pool_drain_ttl_secs: AtomicU64::new(me_pool_drain_ttl_secs),
             me_pool_force_close_secs: AtomicU64::new(me_pool_force_close_secs),
             me_pool_min_fresh_ratio_permille: AtomicU32::new(Self::ratio_to_permille(
@@ -343,6 +451,15 @@ impl MePool {
             secret_atomic_snapshot: AtomicBool::new(me_secret_atomic_snapshot),
             me_deterministic_writer_sort: AtomicBool::new(me_deterministic_writer_sort),
             me_socks_kdf_policy: AtomicU8::new(me_socks_kdf_policy.as_u8()),
+            me_route_no_writer_mode: AtomicU8::new(me_route_no_writer_mode.as_u8()),
+            me_route_no_writer_wait: Duration::from_millis(me_route_no_writer_wait_ms),
+            me_route_inline_recovery_attempts,
+            me_route_inline_recovery_wait: Duration::from_millis(me_route_inline_recovery_wait_ms),
+            me_health_interval_ms_unhealthy: AtomicU64::new(me_health_interval_ms_unhealthy.max(1)),
+            me_health_interval_ms_healthy: AtomicU64::new(me_health_interval_ms_healthy.max(1)),
+            me_warn_rate_limit_ms: AtomicU64::new(me_warn_rate_limit_ms.max(1)),
+            runtime_ready: AtomicBool::new(false),
+            preferred_endpoints_by_dc: Arc::new(RwLock::new(preferred_endpoints_by_dc)),
         })
     }
 
@@ -350,6 +467,14 @@ impl MePool {
         self.active_generation.load(Ordering::Relaxed)
     }
 
+    pub fn set_runtime_ready(&self, ready: bool) {
+        self.runtime_ready.store(ready, Ordering::Relaxed);
+    }
+
+    pub fn is_runtime_ready(&self) -> bool {
+        self.runtime_ready.load(Ordering::Relaxed)
+    }
+
     pub fn update_runtime_reinit_policy(
         &self,
         hardswap: bool,
@@ -373,7 +498,19 @@ impl MePool {
         floor_mode: MeFloorMode,
         adaptive_floor_idle_secs: u64,
         adaptive_floor_min_writers_single_endpoint: u8,
+        adaptive_floor_min_writers_multi_endpoint: u8,
         adaptive_floor_recover_grace_secs: u64,
+        adaptive_floor_writers_per_core_total: u16,
+        adaptive_floor_cpu_cores_override: u16,
+        adaptive_floor_max_extra_writers_single_per_core: u16,
+        adaptive_floor_max_extra_writers_multi_per_core: u16,
+        adaptive_floor_max_active_writers_per_core: u16,
+        adaptive_floor_max_warm_writers_per_core: u16,
+        adaptive_floor_max_active_writers_global: u32,
+        adaptive_floor_max_warm_writers_global: u32,
+        me_health_interval_ms_unhealthy: u64,
+        me_health_interval_ms_healthy: u64,
+        me_warn_rate_limit_ms: u64,
     ) {
         self.hardswap.store(hardswap, Ordering::Relaxed);
         self.me_pool_drain_ttl_secs
@@ -417,8 +554,44 @@ impl MePool {
             .store(adaptive_floor_idle_secs, Ordering::Relaxed);
         self.me_adaptive_floor_min_writers_single_endpoint
             .store(adaptive_floor_min_writers_single_endpoint, Ordering::Relaxed);
+        self.me_adaptive_floor_min_writers_multi_endpoint
+            .store(adaptive_floor_min_writers_multi_endpoint, Ordering::Relaxed);
         self.me_adaptive_floor_recover_grace_secs
             .store(adaptive_floor_recover_grace_secs, Ordering::Relaxed);
+        self.me_adaptive_floor_writers_per_core_total
+            .store(adaptive_floor_writers_per_core_total as u32, Ordering::Relaxed);
+        self.me_adaptive_floor_cpu_cores_override
+            .store(adaptive_floor_cpu_cores_override as u32, Ordering::Relaxed);
+        self.me_adaptive_floor_max_extra_writers_single_per_core
+            .store(
+                adaptive_floor_max_extra_writers_single_per_core as u32,
+                Ordering::Relaxed,
+            );
+        self.me_adaptive_floor_max_extra_writers_multi_per_core
+            .store(
+                adaptive_floor_max_extra_writers_multi_per_core as u32,
+                Ordering::Relaxed,
+            );
+        self.me_adaptive_floor_max_active_writers_per_core
+            .store(
+                adaptive_floor_max_active_writers_per_core as u32,
+                Ordering::Relaxed,
+            );
+        self.me_adaptive_floor_max_warm_writers_per_core
+            .store(
+                adaptive_floor_max_warm_writers_per_core as u32,
+                Ordering::Relaxed,
+            );
+        self.me_adaptive_floor_max_active_writers_global
+            .store(adaptive_floor_max_active_writers_global, Ordering::Relaxed);
+        self.me_adaptive_floor_max_warm_writers_global
+            .store(adaptive_floor_max_warm_writers_global, Ordering::Relaxed);
+        self.me_health_interval_ms_unhealthy
+            .store(me_health_interval_ms_unhealthy.max(1), Ordering::Relaxed);
+        self.me_health_interval_ms_healthy
+            .store(me_health_interval_ms_healthy.max(1), Ordering::Relaxed);
+        self.me_warn_rate_limit_ms
+            .store(me_warn_rate_limit_ms.max(1), Ordering::Relaxed);
         if previous_floor_mode != floor_mode {
             self.stats.increment_me_floor_mode_switch_total();
             match (previous_floor_mode, floor_mode) {
@@ -489,6 +662,28 @@ impl MePool {
         self.proxy_secret.read().await.key_selector
     }
 
+    pub(super) async fn non_draining_writer_counts_by_contour(&self) -> (usize, usize, usize) {
+        let ws = self.writers.read().await;
+        let mut active = 0usize;
+        let mut warm = 0usize;
+        for writer in ws.iter() {
+            if writer.draining.load(Ordering::Relaxed) {
+                continue;
+            }
+            match WriterContour::from_u8(writer.contour.load(Ordering::Relaxed)) {
+                WriterContour::Active => active = active.saturating_add(1),
+                WriterContour::Warm => warm = warm.saturating_add(1),
+                WriterContour::Draining => {}
+            }
+        }
+        (active, warm, active.saturating_add(warm))
+    }
+
+    pub(super) async fn active_contour_writer_count_total(&self) -> usize {
+        let (active, _, _) = self.non_draining_writer_counts_by_contour().await;
+        active
+    }
+
     pub(super) async fn secret_snapshot(&self) -> SecretSnapshot {
         self.proxy_secret.read().await.clone()
     }
@@ -525,6 +720,201 @@ impl MePool {
         )
     }
 
+    pub(super) fn adaptive_floor_min_writers_multi_endpoint(&self) -> usize {
+        (self
+            .me_adaptive_floor_min_writers_multi_endpoint
+            .load(Ordering::Relaxed) as usize)
+            .max(1)
+    }
+
+    pub(super) fn adaptive_floor_max_extra_single_per_core(&self) -> usize {
+        self.me_adaptive_floor_max_extra_writers_single_per_core
+            .load(Ordering::Relaxed) as usize
+    }
+
+    pub(super) fn adaptive_floor_max_extra_multi_per_core(&self) -> usize {
+        self.me_adaptive_floor_max_extra_writers_multi_per_core
+            .load(Ordering::Relaxed) as usize
+    }
+
+    pub(super) fn adaptive_floor_max_active_writers_per_core(&self) -> usize {
+        (self
+            .me_adaptive_floor_max_active_writers_per_core
+            .load(Ordering::Relaxed) as usize)
+            .max(1)
+    }
+
+    pub(super) fn adaptive_floor_max_warm_writers_per_core(&self) -> usize {
+        (self
+            .me_adaptive_floor_max_warm_writers_per_core
+            .load(Ordering::Relaxed) as usize)
+            .max(1)
+    }
+
+    pub(super) fn adaptive_floor_max_active_writers_global(&self) -> usize {
+        (self
+            .me_adaptive_floor_max_active_writers_global
+            .load(Ordering::Relaxed) as usize)
+            .max(1)
+    }
+
+    pub(super) fn adaptive_floor_max_warm_writers_global(&self) -> usize {
+        (self
+            .me_adaptive_floor_max_warm_writers_global
+            .load(Ordering::Relaxed) as usize)
+            .max(1)
+    }
+
+    pub(super) fn adaptive_floor_detected_cpu_cores(&self) -> usize {
+        std::thread::available_parallelism()
+            .map(|value| value.get())
+            .unwrap_or(1)
+            .max(1)
+    }
+
+    pub(super) fn adaptive_floor_effective_cpu_cores(&self) -> usize {
+        let detected = self.adaptive_floor_detected_cpu_cores();
+        let override_cores = self
+            .me_adaptive_floor_cpu_cores_override
+            .load(Ordering::Relaxed) as usize;
+        let effective = if override_cores == 0 {
+            detected
+        } else {
+            override_cores.max(1)
+        };
+        self.me_adaptive_floor_cpu_cores_detected
+            .store(detected as u32, Ordering::Relaxed);
+        self.me_adaptive_floor_cpu_cores_effective
+            .store(effective as u32, Ordering::Relaxed);
+        self.stats
+            .set_me_floor_cpu_cores_detected_gauge(detected as u64);
+        self.stats
+            .set_me_floor_cpu_cores_effective_gauge(effective as u64);
+        effective
+    }
+
+    pub(super) fn adaptive_floor_active_cap_configured_total(&self) -> usize {
+        let cores = self.adaptive_floor_effective_cpu_cores();
+        let per_core_cap = cores.saturating_mul(self.adaptive_floor_max_active_writers_per_core());
+        let configured = per_core_cap.min(self.adaptive_floor_max_active_writers_global());
+        self.me_adaptive_floor_active_cap_configured
+            .store(configured as u64, Ordering::Relaxed);
+        self.stats
+            .set_me_floor_active_cap_configured_gauge(configured as u64);
+        configured
+    }
+
+    pub(super) fn adaptive_floor_warm_cap_configured_total(&self) -> usize {
+        let cores = self.adaptive_floor_effective_cpu_cores();
+        let per_core_cap = cores.saturating_mul(self.adaptive_floor_max_warm_writers_per_core());
+        let configured = per_core_cap.min(self.adaptive_floor_max_warm_writers_global());
+        self.me_adaptive_floor_warm_cap_configured
+            .store(configured as u64, Ordering::Relaxed);
+        self.stats
+            .set_me_floor_warm_cap_configured_gauge(configured as u64);
+        configured
+    }
+
+    pub(super) fn set_adaptive_floor_runtime_caps(
+        &self,
+        active_cap_configured: usize,
+        active_cap_effective: usize,
+        warm_cap_configured: usize,
+        warm_cap_effective: usize,
+        target_writers_total: usize,
+        active_writers_current: usize,
+        warm_writers_current: usize,
+    ) {
+        self.me_adaptive_floor_global_cap_raw
+            .store(active_cap_configured as u64, Ordering::Relaxed);
+        self.me_adaptive_floor_global_cap_effective
+            .store(active_cap_effective as u64, Ordering::Relaxed);
+        self.me_adaptive_floor_target_writers_total
+            .store(target_writers_total as u64, Ordering::Relaxed);
+        self.me_adaptive_floor_active_cap_configured
+            .store(active_cap_configured as u64, Ordering::Relaxed);
+        self.me_adaptive_floor_active_cap_effective
+            .store(active_cap_effective as u64, Ordering::Relaxed);
+        self.me_adaptive_floor_warm_cap_configured
+            .store(warm_cap_configured as u64, Ordering::Relaxed);
+        self.me_adaptive_floor_warm_cap_effective
+            .store(warm_cap_effective as u64, Ordering::Relaxed);
+        self.me_adaptive_floor_active_writers_current
+            .store(active_writers_current as u64, Ordering::Relaxed);
+        self.me_adaptive_floor_warm_writers_current
+            .store(warm_writers_current as u64, Ordering::Relaxed);
+        self.stats
+            .set_me_floor_global_cap_raw_gauge(active_cap_configured as u64);
+        self.stats
+            .set_me_floor_global_cap_effective_gauge(active_cap_effective as u64);
+        self.stats
+            .set_me_floor_target_writers_total_gauge(target_writers_total as u64);
+        self.stats
+            .set_me_floor_active_cap_configured_gauge(active_cap_configured as u64);
+        self.stats
+            .set_me_floor_active_cap_effective_gauge(active_cap_effective as u64);
+        self.stats
+            .set_me_floor_warm_cap_configured_gauge(warm_cap_configured as u64);
+        self.stats
+            .set_me_floor_warm_cap_effective_gauge(warm_cap_effective as u64);
+        self.stats
+            .set_me_writers_active_current_gauge(active_writers_current as u64);
+        self.stats
+            .set_me_writers_warm_current_gauge(warm_writers_current as u64);
+    }
+
+    pub(super) async fn active_coverage_required_total(&self) -> usize {
+        let mut endpoints_by_dc = HashMap::<i32, HashSet<SocketAddr>>::new();
+
+        if self.decision.ipv4_me {
+            let map = self.proxy_map_v4.read().await;
+            for (dc, addrs) in map.iter() {
+                let entry = endpoints_by_dc.entry(*dc).or_default();
+                for (ip, port) in addrs.iter().copied() {
+                    entry.insert(SocketAddr::new(ip, port));
+                }
+            }
+        }
+
+        if self.decision.ipv6_me {
+            let map = self.proxy_map_v6.read().await;
+            for (dc, addrs) in map.iter() {
+                let entry = endpoints_by_dc.entry(*dc).or_default();
+                for (ip, port) in addrs.iter().copied() {
+                    entry.insert(SocketAddr::new(ip, port));
+                }
+            }
+        }
+
+        endpoints_by_dc
+            .values()
+            .map(|endpoints| self.required_writers_for_dc_with_floor_mode(endpoints.len(), false))
+            .sum()
+    }
+
+    pub(super) async fn can_open_writer_for_contour(
+        &self,
+        contour: WriterContour,
+        allow_coverage_override: bool,
+    ) -> bool {
+        let (active_writers, warm_writers, _) = self.non_draining_writer_counts_by_contour().await;
+        match contour {
+            WriterContour::Active => {
+                let active_cap = self.adaptive_floor_active_cap_configured_total();
+                if active_writers < active_cap {
+                    return true;
+                }
+                if !allow_coverage_override {
+                    return false;
+                }
+                let coverage_required = self.active_coverage_required_total().await;
+                active_writers < coverage_required
+            }
+            WriterContour::Warm => warm_writers < self.adaptive_floor_warm_cap_configured_total(),
+            WriterContour::Draining => true,
+        }
+    }
+
     pub(super) fn required_writers_for_dc_with_floor_mode(
         &self,
         endpoint_count: usize,
@@ -534,13 +924,20 @@ impl MePool {
         if !reduce_for_idle {
             return base_required;
         }
-        if endpoint_count != 1 || self.floor_mode() != MeFloorMode::Adaptive {
+        if self.floor_mode() != MeFloorMode::Adaptive {
             return base_required;
         }
-        let min_writers = (self
-            .me_adaptive_floor_min_writers_single_endpoint
-            .load(Ordering::Relaxed) as usize)
-            .max(1);
+        let min_writers = if endpoint_count == 1 {
+            (self
+                .me_adaptive_floor_min_writers_single_endpoint
+                .load(Ordering::Relaxed) as usize)
+                .max(1)
+        } else {
+            (self
+                .me_adaptive_floor_min_writers_multi_endpoint
+                .load(Ordering::Relaxed) as usize)
+                .max(1)
+        };
         base_required.min(min_writers)
     }
 
@@ -599,6 +996,51 @@ impl MePool {
         order
     }
 
+    pub(super) fn default_dc_for_routing(&self) -> i32 {
+        let dc = self.default_dc.load(Ordering::Relaxed);
+        if dc == 0 { 2 } else { dc }
+    }
+
+    pub(super) async fn has_configured_endpoints_for_dc(&self, dc: i32) -> bool {
+        if self.decision.ipv4_me {
+            let map = self.proxy_map_v4.read().await;
+            if map.get(&dc).is_some_and(|endpoints| !endpoints.is_empty()) {
+                return true;
+            }
+        }
+
+        if self.decision.ipv6_me {
+            let map = self.proxy_map_v6.read().await;
+            if map.get(&dc).is_some_and(|endpoints| !endpoints.is_empty()) {
+                return true;
+            }
+        }
+
+        false
+    }
+
+    pub(super) async fn resolve_target_dc_for_routing(&self, target_dc: i32) -> (i32, bool) {
+        if target_dc == 0 {
+            return (self.default_dc_for_routing(), true);
+        }
+
+        if self.has_configured_endpoints_for_dc(target_dc).await {
+            return (target_dc, false);
+        }
+
+        (self.default_dc_for_routing(), true)
+    }
+
+    pub(super) async fn resolve_dc_for_endpoint(&self, addr: SocketAddr) -> i32 {
+        if let Some(cached) = self.endpoint_dc_map.read().await.get(&addr).copied()
+            && let Some(dc) = cached
+        {
+            return dc;
+        }
+
+        self.default_dc_for_routing()
+    }
+
     pub(super) async fn proxy_map_for_family(
         &self,
         family: IpFamily,
@@ -608,4 +1050,123 @@ impl MePool {
             IpFamily::V6 => self.proxy_map_v6.read().await.clone(),
         }
     }
+
+    fn merge_endpoint_dc(
+        endpoint_dc_map: &mut HashMap<SocketAddr, Option<i32>>,
+        dc: i32,
+        ip: IpAddr,
+        port: u16,
+    ) {
+        let endpoint = SocketAddr::new(ip, port);
+        match endpoint_dc_map.get_mut(&endpoint) {
+            None => {
+                endpoint_dc_map.insert(endpoint, Some(dc));
+            }
+            Some(existing) => {
+                if existing.is_some_and(|existing_dc| existing_dc != dc) {
+                    *existing = None;
+                }
+            }
+        }
+    }
+
+    fn build_preferred_endpoints_by_dc(
+        decision: &NetworkDecision,
+        map_v4: &HashMap<i32, Vec<(IpAddr, u16)>>,
+        map_v6: &HashMap<i32, Vec<(IpAddr, u16)>>,
+    ) -> HashMap<i32, Vec<SocketAddr>> {
+        let mut out = HashMap::<i32, Vec<SocketAddr>>::new();
+        let mut dcs = HashSet::<i32>::new();
+        dcs.extend(map_v4.keys().copied());
+        dcs.extend(map_v6.keys().copied());
+
+        for dc in dcs {
+            let v4 = map_v4
+                .get(&dc)
+                .map(|items| {
+                    items
+                        .iter()
+                        .map(|(ip, port)| SocketAddr::new(*ip, *port))
+                        .collect::<Vec<_>>()
+                })
+                .unwrap_or_default();
+            let v6 = map_v6
+                .get(&dc)
+                .map(|items| {
+                    items
+                        .iter()
+                        .map(|(ip, port)| SocketAddr::new(*ip, *port))
+                        .collect::<Vec<_>>()
+                })
+                .unwrap_or_default();
+
+            let mut selected = if decision.effective_multipath {
+                let mut both = Vec::<SocketAddr>::with_capacity(v4.len().saturating_add(v6.len()));
+                if decision.prefer_ipv6() {
+                    both.extend(v6.iter().copied());
+                    both.extend(v4.iter().copied());
+                } else {
+                    both.extend(v4.iter().copied());
+                    both.extend(v6.iter().copied());
+                }
+                both
+            } else if decision.prefer_ipv6() {
+                if !v6.is_empty() { v6 } else { v4 }
+            } else if !v4.is_empty() {
+                v4
+            } else {
+                v6
+            };
+
+            selected.sort_unstable();
+            selected.dedup();
+            out.insert(dc, selected);
+        }
+
+        out
+    }
+
+    fn build_endpoint_dc_map_from_maps(
+        map_v4: &HashMap<i32, Vec<(IpAddr, u16)>>,
+        map_v6: &HashMap<i32, Vec<(IpAddr, u16)>>,
+    ) -> HashMap<SocketAddr, Option<i32>> {
+        let mut endpoint_dc_map = HashMap::<SocketAddr, Option<i32>>::new();
+        for (dc, endpoints) in map_v4 {
+            for (ip, port) in endpoints {
+                Self::merge_endpoint_dc(&mut endpoint_dc_map, *dc, *ip, *port);
+            }
+        }
+        for (dc, endpoints) in map_v6 {
+            for (ip, port) in endpoints {
+                Self::merge_endpoint_dc(&mut endpoint_dc_map, *dc, *ip, *port);
+            }
+        }
+        endpoint_dc_map
+    }
+
+    pub(super) async fn rebuild_endpoint_dc_map(&self) {
+        let map_v4 = self.proxy_map_v4.read().await.clone();
+        let map_v6 = self.proxy_map_v6.read().await.clone();
+        let rebuilt = Self::build_endpoint_dc_map_from_maps(&map_v4, &map_v6);
+        let preferred = Self::build_preferred_endpoints_by_dc(&self.decision, &map_v4, &map_v6);
+        *self.endpoint_dc_map.write().await = rebuilt;
+        *self.preferred_endpoints_by_dc.write().await = preferred;
+    }
+
+    pub(super) async fn preferred_endpoints_for_dc(&self, dc: i32) -> Vec<SocketAddr> {
+        let guard = self.preferred_endpoints_by_dc.read().await;
+        guard.get(&dc).cloned().unwrap_or_default()
+    }
+
+    pub(super) fn health_interval_unhealthy(&self) -> Duration {
+        Duration::from_millis(self.me_health_interval_ms_unhealthy.load(Ordering::Relaxed).max(1))
+    }
+
+    pub(super) fn health_interval_healthy(&self) -> Duration {
+        Duration::from_millis(self.me_health_interval_ms_healthy.load(Ordering::Relaxed).max(1))
+    }
+
+    pub(super) fn warn_rate_limit_duration(&self) -> Duration {
+        Duration::from_millis(self.me_warn_rate_limit_ms.load(Ordering::Relaxed).max(1))
+    }
 }

src/transport/middle_proxy/pool_config.rs

@@ -54,6 +54,7 @@ impl MePool {
                     && let Some(addrs) = guard.get(&k).cloned()
                 {
                     guard.insert(-k, addrs);
+                    changed = true;
                 }
             }
         }
@@ -65,9 +66,14 @@ impl MePool {
                     && let Some(addrs) = guard.get(&k).cloned()
                 {
                     guard.insert(-k, addrs);
+                    changed = true;
                 }
             }
         }
+        if changed {
+            self.rebuild_endpoint_dc_map().await;
+            self.writer_available.notify_waiters();
+        }
         if changed {
             SnapshotApplyOutcome::AppliedChanged
         } else {
@@ -104,7 +110,10 @@ impl MePool {
     pub async fn reconnect_all(self: &Arc<Self>) {
         let ws = self.writers.read().await.clone();
         for w in ws {
-            if let Ok(()) = self.connect_one(w.addr, self.rng.as_ref()).await {
+            if let Ok(()) = self
+                .connect_one_for_dc(w.addr, w.writer_dc, self.rng.as_ref())
+                .await
+            {
                 self.mark_writer_draining(w.id).await;
                 tokio::time::sleep(Duration::from_secs(2)).await;
             }

src/transport/middle_proxy/pool_init.rs

@@ -1,4 +1,4 @@
-use std::collections::{HashMap, HashSet};
+use std::collections::HashSet;
 use std::net::{IpAddr, SocketAddr};
 use std::sync::Arc;
 
@@ -14,10 +14,12 @@ use super::pool::MePool;
 impl MePool {
     pub async fn init(self: &Arc<Self>, pool_size: usize, rng: &Arc<SecureRandom>) -> Result<()> {
         let family_order = self.family_order();
+        let connect_concurrency = self.me_reconnect_max_concurrent_per_dc.max(1) as usize;
         let ks = self.key_selector().await;
         info!(
             me_servers = self.proxy_map_v4.read().await.len(),
             pool_size,
+            connect_concurrency,
             key_selector = format_args!("0x{ks:08x}"),
             secret_len = self.proxy_secret.read().await.secret.len(),
             "Initializing ME pool"
@@ -25,39 +27,54 @@ impl MePool {
 
         for family in family_order {
             let map = self.proxy_map_for_family(family).await;
-            let mut grouped_dc_addrs: HashMap<i32, Vec<(IpAddr, u16)>> = HashMap::new();
-            for (dc, addrs) in map {
-                if addrs.is_empty() {
-                    continue;
-                }
-                grouped_dc_addrs.entry(dc.abs()).or_default().extend(addrs);
-            }
-            let mut dc_addrs: Vec<(i32, Vec<(IpAddr, u16)>)> = grouped_dc_addrs
+            let mut dc_addrs: Vec<(i32, Vec<(IpAddr, u16)>)> = map
                 .into_iter()
                 .map(|(dc, mut addrs)| {
                     addrs.sort_unstable();
                     addrs.dedup();
                     (dc, addrs)
                 })
+                .filter(|(_, addrs)| !addrs.is_empty())
                 .collect();
             dc_addrs.sort_unstable_by_key(|(dc, _)| *dc);
+            dc_addrs.sort_by_key(|(_, addrs)| (addrs.len() != 1, addrs.len()));
 
-            // Ensure at least one live writer per DC group; run missing DCs in parallel.
+            // Stage 1: build base coverage for conditional-cast.
+            // Single-endpoint DCs are prefilled first; multi-endpoint DCs require one live writer.
             let mut join = tokio::task::JoinSet::new();
             for (dc, addrs) in dc_addrs.iter().cloned() {
                 if addrs.is_empty() {
                     continue;
                 }
+                let target_writers = if addrs.len() == 1 {
+                    self.required_writers_for_dc_with_floor_mode(addrs.len(), false)
+                } else {
+                    1usize
+                };
                 let endpoints: HashSet<SocketAddr> = addrs
                     .iter()
                     .map(|(ip, port)| SocketAddr::new(*ip, *port))
                     .collect();
-                if self.active_writer_count_for_endpoints(&endpoints).await > 0 {
+                if self
+                    .active_writer_count_for_dc_endpoints(dc, &endpoints)
+                    .await
+                    >= target_writers
+                {
                     continue;
                 }
                 let pool = Arc::clone(self);
                 let rng_clone = Arc::clone(rng);
-                join.spawn(async move { pool.connect_primary_for_dc(dc, addrs, rng_clone).await });
+                join.spawn(async move {
+                    pool.connect_primary_for_dc(
+                        dc,
+                        addrs,
+                        target_writers,
+                        rng_clone,
+                        connect_concurrency,
+                        true,
+                    )
+                    .await
+                });
             }
             while join.join_next().await.is_some() {}
 
@@ -67,7 +84,7 @@ impl MePool {
                     .iter()
                     .map(|(ip, port)| SocketAddr::new(*ip, *port))
                     .collect();
-                if self.active_writer_count_for_endpoints(&endpoints).await == 0 {
+                if self.active_writer_count_for_dc_endpoints(*dc, &endpoints).await == 0 {
                     missing_dcs.push(*dc);
                 }
             }
@@ -77,47 +94,36 @@ impl MePool {
                 )));
             }
 
-            // Warm reserve writers asynchronously so startup does not block after first working pool is ready.
+            // Stage 2: continue saturating multi-endpoint DC groups in background.
             let pool = Arc::clone(self);
             let rng_clone = Arc::clone(rng);
             let dc_addrs_bg = dc_addrs.clone();
             tokio::spawn(async move {
-                if pool.me_warmup_stagger_enabled {
-                    for (dc, addrs) in &dc_addrs_bg {
-                        for (ip, port) in addrs {
-                            if pool.connection_count() >= pool_size {
-                                break;
-                            }
-                            let addr = SocketAddr::new(*ip, *port);
-                            let jitter = rand::rng()
-                                .random_range(0..=pool.me_warmup_step_jitter.as_millis() as u64);
-                            let delay_ms = pool.me_warmup_step_delay.as_millis() as u64 + jitter;
-                            tokio::time::sleep(std::time::Duration::from_millis(delay_ms)).await;
-                            if let Err(e) = pool.connect_one(addr, rng_clone.as_ref()).await {
-                                debug!(%addr, dc = %dc, error = %e, "Extra ME connect failed (staggered)");
-                            }
-                        }
-                    }
-                } else {
-                    for (dc, addrs) in &dc_addrs_bg {
-                        for (ip, port) in addrs {
-                            if pool.connection_count() >= pool_size {
-                                break;
-                            }
-                            let addr = SocketAddr::new(*ip, *port);
-                            if let Err(e) = pool.connect_one(addr, rng_clone.as_ref()).await {
-                                debug!(%addr, dc = %dc, error = %e, "Extra ME connect failed");
-                            }
-                        }
-                        if pool.connection_count() >= pool_size {
-                            break;
-                        }
+                let mut join_bg = tokio::task::JoinSet::new();
+                for (dc, addrs) in dc_addrs_bg {
+                    if addrs.len() <= 1 {
+                        continue;
                     }
+                    let target_writers = pool.required_writers_for_dc_with_floor_mode(addrs.len(), false);
+                    let pool_clone = Arc::clone(&pool);
+                    let rng_clone_local = Arc::clone(&rng_clone);
+                    join_bg.spawn(async move {
+                        pool_clone
+                            .connect_primary_for_dc(
+                                dc,
+                                addrs,
+                                target_writers,
+                                rng_clone_local,
+                                connect_concurrency,
+                                false,
+                            )
+                            .await
+                    });
                 }
+                while join_bg.join_next().await.is_some() {}
                 debug!(
-                    target_pool_size = pool_size,
                     current_pool_size = pool.connection_count(),
-                    "Background ME reserve warmup finished"
+                    "Background ME saturation warmup finished"
                 );
             });
 
@@ -140,62 +146,111 @@ impl MePool {
         self: Arc<Self>,
         dc: i32,
         mut addrs: Vec<(IpAddr, u16)>,
+        target_writers: usize,
         rng: Arc<SecureRandom>,
+        connect_concurrency: usize,
+        allow_coverage_override: bool,
     ) -> bool {
         if addrs.is_empty() {
             return false;
         }
+        let target_writers = target_writers.max(1);
         addrs.shuffle(&mut rand::rng());
-        if addrs.len() > 1 {
-            let concurrency = 2usize;
+        let endpoints: Vec<SocketAddr> = addrs
+            .iter()
+            .map(|(ip, port)| SocketAddr::new(*ip, *port))
+            .collect();
+        let endpoint_set: HashSet<SocketAddr> = endpoints.iter().copied().collect();
+
+        loop {
+            let alive = self
+                .active_writer_count_for_dc_endpoints(dc, &endpoint_set)
+                .await;
+            if alive >= target_writers {
+                info!(
+                    dc = %dc,
+                    alive,
+                    target_writers,
+                    "ME connected"
+                );
+                return true;
+            }
+
+            let missing = target_writers.saturating_sub(alive).max(1);
+            let concurrency = connect_concurrency.max(1).min(missing);
             let mut join = tokio::task::JoinSet::new();
-            let mut next_idx = 0usize;
+            for _ in 0..concurrency {
+                let pool = Arc::clone(&self);
+                let rng_clone = Arc::clone(&rng);
+                let endpoints_clone = endpoints.clone();
+                let generation = self.current_generation();
+                join.spawn(async move {
+                    pool.connect_endpoints_round_robin_with_generation_contour(
+                        dc,
+                        &endpoints_clone,
+                        rng_clone.as_ref(),
+                        generation,
+                        super::pool::WriterContour::Active,
+                        allow_coverage_override,
+                    )
+                    .await
+                });
+            }
 
-            while next_idx < addrs.len() || !join.is_empty() {
-                while next_idx < addrs.len() && join.len() < concurrency {
-                    let (ip, port) = addrs[next_idx];
-                    next_idx += 1;
-                    let addr = SocketAddr::new(ip, port);
-                    let pool = Arc::clone(&self);
-                    let rng_clone = Arc::clone(&rng);
-                    join.spawn(async move {
-                        (addr, pool.connect_one(addr, rng_clone.as_ref()).await)
-                    });
-                }
-
-                let Some(res) = join.join_next().await else {
-                    break;
-                };
+            let mut progress = false;
+            while let Some(res) = join.join_next().await {
                 match res {
-                    Ok((addr, Ok(()))) => {
-                        info!(%addr, dc = %dc, "ME connected");
-                        join.abort_all();
-                        while join.join_next().await.is_some() {}
-                        return true;
-                    }
-                    Ok((addr, Err(e))) => {
-                        warn!(%addr, dc = %dc, error = %e, "ME connect failed, trying next");
+                    Ok(true) => {
+                        progress = true;
                     }
+                    Ok(false) => {}
                     Err(e) => {
                         warn!(dc = %dc, error = %e, "ME connect task failed");
                     }
                 }
             }
-            warn!(dc = %dc, "All ME servers for DC failed at init");
-            return false;
-        }
 
-        for (ip, port) in addrs {
-            let addr = SocketAddr::new(ip, port);
-            match self.connect_one(addr, rng.as_ref()).await {
-                Ok(()) => {
-                    info!(%addr, dc = %dc, "ME connected");
-                    return true;
+            let alive_after = self
+                .active_writer_count_for_dc_endpoints(dc, &endpoint_set)
+                .await;
+            if alive_after >= target_writers {
+                info!(
+                    dc = %dc,
+                    alive = alive_after,
+                    target_writers,
+                    "ME connected"
+                );
+                return true;
+            }
+            if !progress {
+                let active_writers_current = self.active_contour_writer_count_total().await;
+                let active_cap_configured = self.adaptive_floor_active_cap_configured_total();
+                if !allow_coverage_override && active_writers_current >= active_cap_configured {
+                    info!(
+                        dc = %dc,
+                        alive = alive_after,
+                        target_writers,
+                        active_writers_current,
+                        active_cap_configured,
+                        "ME init saturation stopped by active writer cap"
+                    );
+                } else {
+                    warn!(
+                        dc = %dc,
+                        alive = alive_after,
+                        target_writers,
+                        "All ME servers for DC failed at init"
+                    );
                 }
-                Err(e) => warn!(%addr, dc = %dc, error = %e, "ME connect failed, trying next"),
+                return false;
+            }
+
+            if self.me_warmup_stagger_enabled {
+                let jitter = rand::rng()
+                    .random_range(0..=self.me_warmup_step_jitter.as_millis() as u64);
+                let delay_ms = self.me_warmup_step_delay.as_millis() as u64 + jitter;
+                tokio::time::sleep(std::time::Duration::from_millis(delay_ms)).await;
             }
         }
-        warn!(dc = %dc, "All ME servers for DC failed at init");
-        false
     }
 }

src/transport/middle_proxy/pool_nat.rs

@@ -248,6 +248,43 @@ impl MePool {
             }
         }
 
+        let _singleflight_guard = if use_shared_cache {
+            Some(match family {
+                IpFamily::V4 => self.nat_reflection_singleflight_v4.lock().await,
+                IpFamily::V6 => self.nat_reflection_singleflight_v6.lock().await,
+            })
+        } else {
+            None
+        };
+
+        if use_shared_cache
+            && let Some(until) = *self.stun_backoff_until.read().await
+            && Instant::now() < until
+        {
+            if let Ok(cache) = self.nat_reflection_cache.try_lock() {
+                let slot = match family {
+                    IpFamily::V4 => cache.v4,
+                    IpFamily::V6 => cache.v6,
+                };
+                return slot.map(|(_, addr)| addr);
+            }
+            return None;
+        }
+
+        if use_shared_cache
+            && let Ok(mut cache) = self.nat_reflection_cache.try_lock()
+        {
+            let slot = match family {
+                IpFamily::V4 => &mut cache.v4,
+                IpFamily::V6 => &mut cache.v6,
+            };
+            if let Some((ts, addr)) = slot
+                && ts.elapsed() < STUN_CACHE_TTL
+            {
+                return Some(*addr);
+            }
+        }
+
         let attempt = if use_shared_cache {
             self.nat_probe_attempts.fetch_add(1, std::sync::atomic::Ordering::Relaxed)
         } else {

src/transport/middle_proxy/pool_refill.rs

@@ -9,7 +9,7 @@ use tracing::{debug, info, warn};
 use crate::crypto::SecureRandom;
 use crate::network::IpFamily;
 
-use super::pool::{MePool, RefillDcKey, WriterContour};
+use super::pool::{MePool, RefillDcKey, RefillEndpointKey, WriterContour};
 
 const ME_FLAP_UPTIME_THRESHOLD_SECS: u64 = 20;
 const ME_FLAP_QUARANTINE_SECS: u64 = 25;
@@ -82,80 +82,36 @@ impl MePool {
         Vec::new()
     }
 
-    pub(super) async fn has_refill_inflight_for_endpoints(&self, endpoints: &[SocketAddr]) -> bool {
-        if endpoints.is_empty() {
-            return false;
-        }
-
-        {
-            let guard = self.refill_inflight.lock().await;
-            if endpoints.iter().any(|addr| guard.contains(addr)) {
-                return true;
-            }
-        }
-
-        let dc_keys = self.resolve_refill_dc_keys_for_endpoints(endpoints).await;
-        if dc_keys.is_empty() {
-            return false;
-        }
+    pub(super) async fn has_refill_inflight_for_dc_key(&self, key: RefillDcKey) -> bool {
         let guard = self.refill_inflight_dc.lock().await;
-        dc_keys.iter().any(|key| guard.contains(key))
-    }
-
-    async fn resolve_refill_dc_key_for_addr(&self, addr: SocketAddr) -> Option<RefillDcKey> {
-        let family = if addr.is_ipv4() {
-            IpFamily::V4
-        } else {
-            IpFamily::V6
-        };
-        let map = self.proxy_map_for_family(family).await;
-        for (dc, endpoints) in map {
-            if endpoints
-                .into_iter()
-                .any(|(ip, port)| SocketAddr::new(ip, port) == addr)
-            {
-                return Some(RefillDcKey {
-                    dc: dc.abs(),
-                    family,
-                });
-            }
-        }
-        None
-    }
-
-    async fn resolve_refill_dc_keys_for_endpoints(
-        &self,
-        endpoints: &[SocketAddr],
-    ) -> HashSet<RefillDcKey> {
-        let mut out = HashSet::<RefillDcKey>::new();
-        for addr in endpoints {
-            if let Some(key) = self.resolve_refill_dc_key_for_addr(*addr).await {
-                out.insert(key);
-            }
-        }
-        out
+        guard.contains(&key)
     }
 
     pub(super) async fn connect_endpoints_round_robin(
         self: &Arc<Self>,
+        dc: i32,
         endpoints: &[SocketAddr],
         rng: &SecureRandom,
     ) -> bool {
         self.connect_endpoints_round_robin_with_generation_contour(
+            dc,
             endpoints,
             rng,
             self.current_generation(),
             WriterContour::Active,
+            false,
         )
         .await
     }
 
     pub(super) async fn connect_endpoints_round_robin_with_generation_contour(
         self: &Arc<Self>,
+        dc: i32,
         endpoints: &[SocketAddr],
         rng: &SecureRandom,
         generation: u64,
         contour: WriterContour,
+        allow_coverage_override: bool,
     ) -> bool {
         let candidates = self.connectable_endpoints(endpoints).await;
         if candidates.is_empty() {
@@ -166,7 +122,14 @@ impl MePool {
             let idx = (start + offset) % candidates.len();
             let addr = candidates[idx];
             match self
-                .connect_one_with_generation_contour(addr, rng, generation, contour)
+                .connect_one_with_generation_contour_for_dc_with_cap_policy(
+                    addr,
+                    rng,
+                    generation,
+                    contour,
+                    dc,
+                    allow_coverage_override,
+                )
                 .await
             {
                 Ok(()) => return true,
@@ -176,48 +139,23 @@ impl MePool {
         false
     }
 
-    async fn endpoints_for_same_dc(&self, addr: SocketAddr) -> Vec<SocketAddr> {
-        let mut target_dc = HashSet::<i32>::new();
+    async fn endpoints_for_dc(&self, target_dc: i32) -> Vec<SocketAddr> {
         let mut endpoints = HashSet::<SocketAddr>::new();
 
         if self.decision.ipv4_me {
-            let map = self.proxy_map_v4.read().await.clone();
-            for (dc, addrs) in &map {
-                if addrs
-                    .iter()
-                    .any(|(ip, port)| SocketAddr::new(*ip, *port) == addr)
-                {
-                    target_dc.insert(dc.abs());
-                }
-            }
-            for dc in &target_dc {
-                for key in [*dc, -*dc] {
-                    if let Some(addrs) = map.get(&key) {
-                        for (ip, port) in addrs {
-                            endpoints.insert(SocketAddr::new(*ip, *port));
-                        }
-                    }
+            let map = self.proxy_map_v4.read().await;
+            if let Some(addrs) = map.get(&target_dc) {
+                for (ip, port) in addrs {
+                    endpoints.insert(SocketAddr::new(*ip, *port));
                 }
             }
         }
 
         if self.decision.ipv6_me {
-            let map = self.proxy_map_v6.read().await.clone();
-            for (dc, addrs) in &map {
-                if addrs
-                    .iter()
-                    .any(|(ip, port)| SocketAddr::new(*ip, *port) == addr)
-                {
-                    target_dc.insert(dc.abs());
-                }
-            }
-            for dc in &target_dc {
-                for key in [*dc, -*dc] {
-                    if let Some(addrs) = map.get(&key) {
-                        for (ip, port) in addrs {
-                            endpoints.insert(SocketAddr::new(*ip, *port));
-                        }
-                    }
+            let map = self.proxy_map_v6.read().await;
+            if let Some(addrs) = map.get(&target_dc) {
+                for (ip, port) in addrs {
+                    endpoints.insert(SocketAddr::new(*ip, *port));
                 }
             }
         }
@@ -227,14 +165,14 @@ impl MePool {
         sorted
     }
 
-    async fn refill_writer_after_loss(self: &Arc<Self>, addr: SocketAddr) -> bool {
+    async fn refill_writer_after_loss(self: &Arc<Self>, addr: SocketAddr, writer_dc: i32) -> bool {
         let fast_retries = self.me_reconnect_fast_retry_count.max(1);
         let same_endpoint_quarantined = self.is_endpoint_quarantined(addr).await;
 
         if !same_endpoint_quarantined {
             for attempt in 0..fast_retries {
                 self.stats.increment_me_reconnect_attempt();
-                match self.connect_one(addr, self.rng.as_ref()).await {
+                match self.connect_one_for_dc(addr, writer_dc, self.rng.as_ref()).await {
                     Ok(()) => {
                         self.stats.increment_me_reconnect_success();
                         self.stats.increment_me_writer_restored_same_endpoint_total();
@@ -262,7 +200,7 @@ impl MePool {
             );
         }
 
-        let dc_endpoints = self.endpoints_for_same_dc(addr).await;
+        let dc_endpoints = self.endpoints_for_dc(writer_dc).await;
         if dc_endpoints.is_empty() {
             self.stats.increment_me_refill_failed_total();
             return false;
@@ -271,7 +209,7 @@ impl MePool {
         for attempt in 0..fast_retries {
             self.stats.increment_me_reconnect_attempt();
             if self
-                .connect_endpoints_round_robin(&dc_endpoints, self.rng.as_ref())
+                .connect_endpoints_round_robin(writer_dc, &dc_endpoints, self.rng.as_ref())
                 .await
             {
                 self.stats.increment_me_reconnect_success();
@@ -289,48 +227,63 @@ impl MePool {
         false
     }
 
-    pub(crate) fn trigger_immediate_refill(self: &Arc<Self>, addr: SocketAddr) {
+    pub(crate) fn trigger_immediate_refill_for_dc(self: &Arc<Self>, addr: SocketAddr, writer_dc: i32) {
+        let endpoint_key = RefillEndpointKey {
+            dc: writer_dc,
+            addr,
+        };
+        let pre_inserted = if let Ok(mut guard) = self.refill_inflight.try_lock() {
+            if !guard.insert(endpoint_key) {
+                self.stats.increment_me_refill_skipped_inflight_total();
+                return;
+            }
+            true
+        } else {
+            false
+        };
+
         let pool = Arc::clone(self);
         tokio::spawn(async move {
-            let dc_endpoints = pool.endpoints_for_same_dc(addr).await;
-            let dc_keys = pool.resolve_refill_dc_keys_for_endpoints(&dc_endpoints).await;
+            let dc_key = RefillDcKey {
+                dc: writer_dc,
+                family: if addr.is_ipv4() {
+                    IpFamily::V4
+                } else {
+                    IpFamily::V6
+                },
+            };
 
-            {
+            if !pre_inserted {
                 let mut guard = pool.refill_inflight.lock().await;
-                if !guard.insert(addr) {
+                if !guard.insert(endpoint_key) {
                     pool.stats.increment_me_refill_skipped_inflight_total();
                     return;
                 }
             }
 
-            if !dc_keys.is_empty() {
+            {
                 let mut dc_guard = pool.refill_inflight_dc.lock().await;
-                if dc_keys.iter().any(|key| dc_guard.contains(key)) {
+                if dc_guard.contains(&dc_key) {
                     pool.stats.increment_me_refill_skipped_inflight_total();
                     drop(dc_guard);
                     let mut guard = pool.refill_inflight.lock().await;
-                    guard.remove(&addr);
+                    guard.remove(&endpoint_key);
                     return;
                 }
-                dc_guard.extend(dc_keys.iter().copied());
+                dc_guard.insert(dc_key);
             }
 
             pool.stats.increment_me_refill_triggered_total();
-
-            let restored = pool.refill_writer_after_loss(addr).await;
+            let restored = pool.refill_writer_after_loss(addr, writer_dc).await;
             if !restored {
-                warn!(%addr, "ME immediate refill failed");
+                warn!(%addr, dc = writer_dc, "ME immediate refill failed");
             }
 
             let mut guard = pool.refill_inflight.lock().await;
-            guard.remove(&addr);
+            guard.remove(&endpoint_key);
             drop(guard);
-            if !dc_keys.is_empty() {
-                let mut dc_guard = pool.refill_inflight_dc.lock().await;
-                for key in &dc_keys {
-                    dc_guard.remove(key);
-                }
-            }
+            let mut dc_guard = pool.refill_inflight_dc.lock().await;
+            dc_guard.remove(&dc_key);
         });
     }
 }

src/transport/middle_proxy/pool_reinit.rs

@@ -62,7 +62,7 @@ impl MePool {
 
     fn coverage_ratio(
         desired_by_dc: &HashMap<i32, HashSet<SocketAddr>>,
-        active_writer_addrs: &HashSet<SocketAddr>,
+        active_writer_addrs: &HashSet<(i32, SocketAddr)>,
     ) -> (f32, Vec<i32>) {
         if desired_by_dc.is_empty() {
             return (1.0, Vec::new());
@@ -76,7 +76,7 @@ impl MePool {
             }
             if endpoints
                 .iter()
-                .any(|addr| active_writer_addrs.contains(addr))
+                .any(|addr| active_writer_addrs.contains(&(*dc, *addr)))
             {
                 covered += 1;
             } else {
@@ -91,32 +91,25 @@ impl MePool {
     }
 
     pub async fn reconcile_connections(self: &Arc<Self>, rng: &SecureRandom) {
-        let writers = self.writers.read().await;
-        let current: HashSet<SocketAddr> = writers
-            .iter()
-            .filter(|w| !w.draining.load(Ordering::Relaxed))
-            .map(|w| w.addr)
-            .collect();
-        drop(writers);
-
         for family in self.family_order() {
             let map = self.proxy_map_for_family(family).await;
-            for (_dc, addrs) in &map {
+            for (dc, addrs) in &map {
                 let dc_addrs: Vec<SocketAddr> = addrs
                     .iter()
                     .map(|(ip, port)| SocketAddr::new(*ip, *port))
                     .collect();
-                if !dc_addrs.iter().any(|a| current.contains(a)) {
+                let dc_endpoints: HashSet<SocketAddr> = dc_addrs.iter().copied().collect();
+                if self.active_writer_count_for_dc_endpoints(*dc, &dc_endpoints).await == 0 {
                     let mut shuffled = dc_addrs.clone();
                     shuffled.shuffle(&mut rand::rng());
                     for addr in shuffled {
-                        if self.connect_one(addr, rng).await.is_ok() {
+                        if self.connect_one_for_dc(addr, *dc, rng).await.is_ok() {
                             break;
                         }
                     }
                 }
             }
-            if !self.decision.effective_multipath && !current.is_empty() {
+            if !self.decision.effective_multipath && self.connection_count() > 0 {
                 break;
             }
         }
@@ -128,7 +121,7 @@ impl MePool {
         if self.decision.ipv4_me {
             let map_v4 = self.proxy_map_v4.read().await.clone();
             for (dc, addrs) in map_v4 {
-                let entry = out.entry(dc.abs()).or_default();
+                let entry = out.entry(dc).or_default();
                 for (ip, port) in addrs {
                     entry.insert(SocketAddr::new(ip, port));
                 }
@@ -138,7 +131,7 @@ impl MePool {
         if self.decision.ipv6_me {
             let map_v6 = self.proxy_map_v6.read().await.clone();
             for (dc, addrs) in map_v6 {
-                let entry = out.entry(dc.abs()).or_default();
+                let entry = out.entry(dc).or_default();
                 for (ip, port) in addrs {
                     entry.insert(SocketAddr::new(ip, port));
                 }
@@ -174,26 +167,30 @@ impl MePool {
         core.saturating_add(rand::rng().random_range(0..=jitter))
     }
 
-    async fn fresh_writer_count_for_endpoints(
+    async fn fresh_writer_count_for_dc_endpoints(
         &self,
         generation: u64,
+        dc: i32,
         endpoints: &HashSet<SocketAddr>,
     ) -> usize {
         let ws = self.writers.read().await;
         ws.iter()
             .filter(|w| !w.draining.load(Ordering::Relaxed))
             .filter(|w| w.generation == generation)
+            .filter(|w| w.writer_dc == dc)
             .filter(|w| endpoints.contains(&w.addr))
             .count()
     }
 
-    pub(super) async fn active_writer_count_for_endpoints(
+    pub(super) async fn active_writer_count_for_dc_endpoints(
         &self,
+        dc: i32,
         endpoints: &HashSet<SocketAddr>,
     ) -> usize {
         let ws = self.writers.read().await;
         ws.iter()
             .filter(|w| !w.draining.load(Ordering::Relaxed))
+            .filter(|w| w.writer_dc == dc)
             .filter(|w| endpoints.contains(&w.addr))
             .count()
     }
@@ -220,7 +217,7 @@ impl MePool {
             let required = self.required_writers_for_dc(endpoint_list.len());
             let mut completed = false;
             let mut last_fresh_count = self
-                .fresh_writer_count_for_endpoints(generation, endpoints)
+                .fresh_writer_count_for_dc_endpoints(generation, *dc, endpoints)
                 .await;
 
             for pass_idx in 0..total_passes {
@@ -247,10 +244,12 @@ impl MePool {
 
                     let connected = self
                         .connect_endpoints_round_robin_with_generation_contour(
+                            *dc,
                             &endpoint_list,
                             rng,
                             generation,
                             WriterContour::Warm,
+                            false,
                         )
                         .await;
                     debug!(
@@ -265,7 +264,7 @@ impl MePool {
                 }
 
                 last_fresh_count = self
-                    .fresh_writer_count_for_endpoints(generation, endpoints)
+                    .fresh_writer_count_for_dc_endpoints(generation, *dc, endpoints)
                     .await;
                 if last_fresh_count >= required {
                     completed = true;
@@ -377,10 +376,10 @@ impl MePool {
         }
 
         let writers = self.writers.read().await;
-        let active_writer_addrs: HashSet<SocketAddr> = writers
+        let active_writer_addrs: HashSet<(i32, SocketAddr)> = writers
             .iter()
             .filter(|w| !w.draining.load(Ordering::Relaxed))
-            .map(|w| w.addr)
+            .map(|w| (w.writer_dc, w.addr))
             .collect();
         let min_ratio = Self::permille_to_ratio(
             self.me_pool_min_fresh_ratio_permille
@@ -410,6 +409,7 @@ impl MePool {
                     .iter()
                     .filter(|w| !w.draining.load(Ordering::Relaxed))
                     .filter(|w| w.generation == generation)
+                    .filter(|w| w.writer_dc == *dc)
                     .filter(|w| endpoints.contains(&w.addr))
                     .count();
                 if fresh_count < required {
@@ -438,9 +438,9 @@ impl MePool {
             self.promote_warm_generation_to_active(generation).await;
         }
 
-        let desired_addrs: HashSet<SocketAddr> = desired_by_dc
-            .values()
-            .flat_map(|set| set.iter().copied())
+        let desired_addrs: HashSet<(i32, SocketAddr)> = desired_by_dc
+            .iter()
+            .flat_map(|(dc, set)| set.iter().copied().map(|addr| (*dc, addr)))
             .collect();
 
         let stale_writer_ids: Vec<u64> = writers
@@ -450,7 +450,7 @@ impl MePool {
                 if hardswap {
                     w.generation < generation
                 } else {
-                    !desired_addrs.contains(&w.addr)
+                    !desired_addrs.contains(&(w.writer_dc, w.addr))
                 }
             })
             .map(|w| w.id)

src/transport/middle_proxy/pool_runtime_api.rs

@@ -0,0 +1,128 @@
+use std::collections::HashMap;
+use std::time::Instant;
+
+use super::pool::{MePool, RefillDcKey};
+use crate::network::IpFamily;
+
+#[derive(Clone, Debug)]
+pub(crate) struct MeApiRefillDcSnapshot {
+    pub dc: i16,
+    pub family: &'static str,
+    pub inflight: usize,
+}
+
+#[derive(Clone, Debug)]
+pub(crate) struct MeApiRefillSnapshot {
+    pub inflight_endpoints_total: usize,
+    pub inflight_dc_total: usize,
+    pub by_dc: Vec<MeApiRefillDcSnapshot>,
+}
+
+#[derive(Clone, Debug)]
+pub(crate) struct MeApiNatReflectionSnapshot {
+    pub addr: std::net::SocketAddr,
+    pub age_secs: u64,
+}
+
+#[derive(Clone, Debug)]
+pub(crate) struct MeApiNatStunSnapshot {
+    pub nat_probe_enabled: bool,
+    pub nat_probe_disabled_runtime: bool,
+    pub nat_probe_attempts: u8,
+    pub configured_servers: Vec<String>,
+    pub live_servers: Vec<String>,
+    pub reflection_v4: Option<MeApiNatReflectionSnapshot>,
+    pub reflection_v6: Option<MeApiNatReflectionSnapshot>,
+    pub stun_backoff_remaining_ms: Option<u64>,
+}
+
+impl MePool {
+    pub(crate) async fn api_refill_snapshot(&self) -> MeApiRefillSnapshot {
+        let inflight_endpoints_total = self.refill_inflight.lock().await.len();
+        let inflight_dc_keys = self
+            .refill_inflight_dc
+            .lock()
+            .await
+            .iter()
+            .copied()
+            .collect::<Vec<RefillDcKey>>();
+
+        let mut by_dc_map = HashMap::<(i16, &'static str), usize>::new();
+        for key in inflight_dc_keys {
+            let family = match key.family {
+                IpFamily::V4 => "v4",
+                IpFamily::V6 => "v6",
+            };
+            let dc = key.dc as i16;
+            *by_dc_map.entry((dc, family)).or_insert(0) += 1;
+        }
+
+        let mut by_dc = by_dc_map
+            .into_iter()
+            .map(|((dc, family), inflight)| MeApiRefillDcSnapshot {
+                dc,
+                family,
+                inflight,
+            })
+            .collect::<Vec<_>>();
+        by_dc.sort_by_key(|entry| (entry.dc, entry.family));
+
+        MeApiRefillSnapshot {
+            inflight_endpoints_total,
+            inflight_dc_total: by_dc.len(),
+            by_dc,
+        }
+    }
+
+    pub(crate) async fn api_nat_stun_snapshot(&self) -> MeApiNatStunSnapshot {
+        let now = Instant::now();
+        let mut configured_servers = if !self.nat_stun_servers.is_empty() {
+            self.nat_stun_servers.clone()
+        } else if let Some(stun) = &self.nat_stun {
+            if stun.trim().is_empty() {
+                Vec::new()
+            } else {
+                vec![stun.clone()]
+            }
+        } else {
+            Vec::new()
+        };
+        configured_servers.sort();
+        configured_servers.dedup();
+
+        let mut live_servers = self.nat_stun_live_servers.read().await.clone();
+        live_servers.sort();
+        live_servers.dedup();
+
+        let reflection = self.nat_reflection_cache.lock().await;
+        let reflection_v4 = reflection.v4.map(|(ts, addr)| MeApiNatReflectionSnapshot {
+            addr,
+            age_secs: now.saturating_duration_since(ts).as_secs(),
+        });
+        let reflection_v6 = reflection.v6.map(|(ts, addr)| MeApiNatReflectionSnapshot {
+            addr,
+            age_secs: now.saturating_duration_since(ts).as_secs(),
+        });
+        drop(reflection);
+
+        let backoff_until = *self.stun_backoff_until.read().await;
+        let stun_backoff_remaining_ms = backoff_until.and_then(|until| {
+            (until > now).then_some(until.duration_since(now).as_millis() as u64)
+        });
+
+        MeApiNatStunSnapshot {
+            nat_probe_enabled: self.nat_probe,
+            nat_probe_disabled_runtime: self
+                .nat_probe_disabled
+                .load(std::sync::atomic::Ordering::Relaxed),
+            nat_probe_attempts: self
+                .nat_probe_attempts
+                .load(std::sync::atomic::Ordering::Relaxed),
+            configured_servers,
+            live_servers,
+            reflection_v4,
+            reflection_v6,
+            stun_backoff_remaining_ms,
+        }
+    }
+}

src/transport/middle_proxy/pool_status.rs

@@ -1,5 +1,5 @@
 use std::collections::{BTreeMap, BTreeSet, HashMap};
-use std::net::SocketAddr;
+use std::net::{IpAddr, SocketAddr};
 use std::sync::atomic::Ordering;
 use std::time::Instant;
 
@@ -28,6 +28,10 @@ pub(crate) struct MeApiDcStatusSnapshot {
     pub available_endpoints: usize,
     pub available_pct: f64,
     pub required_writers: usize,
+    pub floor_min: usize,
+    pub floor_target: usize,
+    pub floor_max: usize,
+    pub floor_capped: bool,
     pub alive_writers: usize,
     pub coverage_pct: f64,
     pub rtt_ms: Option<f64>,
@@ -72,7 +76,27 @@ pub(crate) struct MeApiRuntimeSnapshot {
     pub floor_mode: &'static str,
     pub adaptive_floor_idle_secs: u64,
     pub adaptive_floor_min_writers_single_endpoint: u8,
+    pub adaptive_floor_min_writers_multi_endpoint: u8,
     pub adaptive_floor_recover_grace_secs: u64,
+    pub adaptive_floor_writers_per_core_total: u16,
+    pub adaptive_floor_cpu_cores_override: u16,
+    pub adaptive_floor_max_extra_writers_single_per_core: u16,
+    pub adaptive_floor_max_extra_writers_multi_per_core: u16,
+    pub adaptive_floor_max_active_writers_per_core: u16,
+    pub adaptive_floor_max_warm_writers_per_core: u16,
+    pub adaptive_floor_max_active_writers_global: u32,
+    pub adaptive_floor_max_warm_writers_global: u32,
+    pub adaptive_floor_cpu_cores_detected: u32,
+    pub adaptive_floor_cpu_cores_effective: u32,
+    pub adaptive_floor_global_cap_raw: u64,
+    pub adaptive_floor_global_cap_effective: u64,
+    pub adaptive_floor_target_writers_total: u64,
+    pub adaptive_floor_active_cap_configured: u64,
+    pub adaptive_floor_active_cap_effective: u64,
+    pub adaptive_floor_warm_cap_configured: u64,
+    pub adaptive_floor_warm_cap_effective: u64,
+    pub adaptive_floor_active_writers_current: u64,
+    pub adaptive_floor_warm_writers_current: u64,
     pub me_keepalive_enabled: bool,
     pub me_keepalive_interval_secs: u64,
     pub me_keepalive_jitter_secs: u64,
@@ -100,48 +124,95 @@ pub(crate) struct MeApiRuntimeSnapshot {
 }
 
 impl MePool {
+    pub(crate) async fn admission_ready_conditional_cast(&self) -> bool {
+        let mut endpoints_by_dc = BTreeMap::<i16, BTreeSet<SocketAddr>>::new();
+        if self.decision.ipv4_me {
+            let map = self.proxy_map_v4.read().await.clone();
+            extend_signed_endpoints(&mut endpoints_by_dc, map);
+        }
+        if self.decision.ipv6_me {
+            let map = self.proxy_map_v6.read().await.clone();
+            extend_signed_endpoints(&mut endpoints_by_dc, map);
+        }
+
+        if endpoints_by_dc.is_empty() {
+            return false;
+        }
+
+        let writers = self.writers.read().await.clone();
+        let mut live_writers_by_dc = HashMap::<i16, usize>::new();
+        for writer in writers {
+            if writer.draining.load(Ordering::Relaxed) {
+                continue;
+            }
+            if let Ok(dc) = i16::try_from(writer.writer_dc) {
+                *live_writers_by_dc.entry(dc).or_insert(0) += 1;
+            }
+        }
+
+        for dc in endpoints_by_dc.keys() {
+            let alive = live_writers_by_dc.get(dc).copied().unwrap_or(0);
+            if alive == 0 {
+                return false;
+            }
+        }
+
+        true
+    }
+
+    #[allow(dead_code)]
+    pub(crate) async fn admission_ready_full_floor(&self) -> bool {
+        let mut endpoints_by_dc = BTreeMap::<i16, BTreeSet<SocketAddr>>::new();
+        if self.decision.ipv4_me {
+            let map = self.proxy_map_v4.read().await.clone();
+            extend_signed_endpoints(&mut endpoints_by_dc, map);
+        }
+        if self.decision.ipv6_me {
+            let map = self.proxy_map_v6.read().await.clone();
+            extend_signed_endpoints(&mut endpoints_by_dc, map);
+        }
+
+        if endpoints_by_dc.is_empty() {
+            return false;
+        }
+
+        let writers = self.writers.read().await.clone();
+        let mut live_writers_by_dc = HashMap::<i16, usize>::new();
+        for writer in writers {
+            if writer.draining.load(Ordering::Relaxed) {
+                continue;
+            }
+            if let Ok(dc) = i16::try_from(writer.writer_dc) {
+                *live_writers_by_dc.entry(dc).or_insert(0) += 1;
+            }
+        }
+
+        for (dc, endpoints) in endpoints_by_dc {
+            let endpoint_count = endpoints.len();
+            if endpoint_count == 0 {
+                return false;
+            }
+            let required = self.required_writers_for_dc_with_floor_mode(endpoint_count, false);
+            let alive = live_writers_by_dc.get(&dc).copied().unwrap_or(0);
+            if alive < required {
+                return false;
+            }
+        }
+
+        true
+    }
+
     pub(crate) async fn api_status_snapshot(&self) -> MeApiStatusSnapshot {
         let now_epoch_secs = Self::now_epoch_secs();
 
         let mut endpoints_by_dc = BTreeMap::<i16, BTreeSet<SocketAddr>>::new();
         if self.decision.ipv4_me {
             let map = self.proxy_map_v4.read().await.clone();
-            for (dc, addrs) in map {
-                let abs_dc = dc.abs();
-                if abs_dc == 0 {
-                    continue;
-                }
-                let Ok(dc_idx) = i16::try_from(abs_dc) else {
-                    continue;
-                };
-                let entry = endpoints_by_dc.entry(dc_idx).or_default();
-                for (ip, port) in addrs {
-                    entry.insert(SocketAddr::new(ip, port));
-                }
-            }
+            extend_signed_endpoints(&mut endpoints_by_dc, map);
         }
         if self.decision.ipv6_me {
             let map = self.proxy_map_v6.read().await.clone();
-            for (dc, addrs) in map {
-                let abs_dc = dc.abs();
-                if abs_dc == 0 {
-                    continue;
-                }
-                let Ok(dc_idx) = i16::try_from(abs_dc) else {
-                    continue;
-                };
-                let entry = endpoints_by_dc.entry(dc_idx).or_default();
-                for (ip, port) in addrs {
-                    entry.insert(SocketAddr::new(ip, port));
-                }
-            }
-        }
-
-        let mut endpoint_to_dc = HashMap::<SocketAddr, i16>::new();
-        for (dc, endpoints) in &endpoints_by_dc {
-            for endpoint in endpoints {
-                endpoint_to_dc.entry(*endpoint).or_insert(*dc);
-            }
+            extend_signed_endpoints(&mut endpoints_by_dc, map);
         }
 
         let configured_dc_groups = endpoints_by_dc.len();
@@ -157,14 +228,14 @@ impl MePool {
         let rtt = self.rtt_stats.lock().await.clone();
         let writers = self.writers.read().await.clone();
 
-        let mut live_writers_by_endpoint = HashMap::<SocketAddr, usize>::new();
+        let mut live_writers_by_dc_endpoint = HashMap::<(i16, SocketAddr), usize>::new();
         let mut live_writers_by_dc = HashMap::<i16, usize>::new();
         let mut dc_rtt_agg = HashMap::<i16, (f64, u64)>::new();
         let mut writer_rows = Vec::<MeApiWriterStatusSnapshot>::with_capacity(writers.len());
 
         for writer in writers {
             let endpoint = writer.addr;
-            let dc = endpoint_to_dc.get(&endpoint).copied();
+            let dc = i16::try_from(writer.writer_dc).ok();
             let draining = writer.draining.load(Ordering::Relaxed);
             let degraded = writer.degraded.load(Ordering::Relaxed);
             let bound_clients = activity
@@ -183,8 +254,10 @@ impl MePool {
             };
 
             if !draining {
-                *live_writers_by_endpoint.entry(endpoint).or_insert(0) += 1;
                 if let Some(dc_idx) = dc {
+                    *live_writers_by_dc_endpoint
+                        .entry((dc_idx, endpoint))
+                        .or_insert(0) += 1;
                     *live_writers_by_dc.entry(dc_idx).or_insert(0) += 1;
                     if let Some(ema_ms) = rtt_ema_ms {
                         let entry = dc_rtt_agg.entry(dc_idx).or_insert((0.0, 0));
@@ -213,14 +286,43 @@ impl MePool {
         let mut dcs = Vec::<MeApiDcStatusSnapshot>::with_capacity(endpoints_by_dc.len());
         let mut available_endpoints = 0usize;
         let mut alive_writers = 0usize;
+        let floor_mode = self.floor_mode();
+        let adaptive_cpu_cores = (self
+            .me_adaptive_floor_cpu_cores_effective
+            .load(Ordering::Relaxed) as usize)
+            .max(1);
         for (dc, endpoints) in endpoints_by_dc {
             let endpoint_count = endpoints.len();
             let dc_available_endpoints = endpoints
                 .iter()
-                .filter(|endpoint| live_writers_by_endpoint.contains_key(endpoint))
+                .filter(|endpoint| live_writers_by_dc_endpoint.contains_key(&(dc, **endpoint)))
                 .count();
+            let base_required = self.required_writers_for_dc(endpoint_count);
             let dc_required_writers =
                 self.required_writers_for_dc_with_floor_mode(endpoint_count, false);
+            let floor_min = if endpoint_count <= 1 {
+                (self
+                    .me_adaptive_floor_min_writers_single_endpoint
+                    .load(Ordering::Relaxed) as usize)
+                    .max(1)
+                    .min(base_required.max(1))
+            } else {
+                (self
+                    .me_adaptive_floor_min_writers_multi_endpoint
+                    .load(Ordering::Relaxed) as usize)
+                    .max(1)
+                    .min(base_required.max(1))
+            };
+            let extra_per_core = if endpoint_count <= 1 {
+                self.me_adaptive_floor_max_extra_writers_single_per_core
+                    .load(Ordering::Relaxed) as usize
+            } else {
+                self.me_adaptive_floor_max_extra_writers_multi_per_core
+                    .load(Ordering::Relaxed) as usize
+            };
+            let floor_max = base_required.saturating_add(adaptive_cpu_cores.saturating_mul(extra_per_core));
+            let floor_capped = matches!(floor_mode, MeFloorMode::Adaptive)
+                && dc_required_writers < base_required;
             let dc_alive_writers = live_writers_by_dc.get(&dc).copied().unwrap_or(0);
             let dc_load = activity
                 .active_sessions_by_target_dc
@@ -240,6 +342,10 @@ impl MePool {
                 available_endpoints: dc_available_endpoints,
                 available_pct: ratio_pct(dc_available_endpoints, endpoint_count),
                 required_writers: dc_required_writers,
+                floor_min,
+                floor_target: dc_required_writers,
+                floor_max,
+                floor_capped,
                 alive_writers: dc_alive_writers,
                 coverage_pct: ratio_pct(dc_alive_writers, dc_required_writers),
                 rtt_ms: dc_rtt_ms,
@@ -316,9 +422,69 @@ impl MePool {
             adaptive_floor_min_writers_single_endpoint: self
                 .me_adaptive_floor_min_writers_single_endpoint
                 .load(Ordering::Relaxed),
+            adaptive_floor_min_writers_multi_endpoint: self
+                .me_adaptive_floor_min_writers_multi_endpoint
+                .load(Ordering::Relaxed),
             adaptive_floor_recover_grace_secs: self
                 .me_adaptive_floor_recover_grace_secs
                 .load(Ordering::Relaxed),
+            adaptive_floor_writers_per_core_total: self
+                .me_adaptive_floor_writers_per_core_total
+                .load(Ordering::Relaxed) as u16,
+            adaptive_floor_cpu_cores_override: self
+                .me_adaptive_floor_cpu_cores_override
+                .load(Ordering::Relaxed) as u16,
+            adaptive_floor_max_extra_writers_single_per_core: self
+                .me_adaptive_floor_max_extra_writers_single_per_core
+                .load(Ordering::Relaxed) as u16,
+            adaptive_floor_max_extra_writers_multi_per_core: self
+                .me_adaptive_floor_max_extra_writers_multi_per_core
+                .load(Ordering::Relaxed) as u16,
+            adaptive_floor_max_active_writers_per_core: self
+                .me_adaptive_floor_max_active_writers_per_core
+                .load(Ordering::Relaxed) as u16,
+            adaptive_floor_max_warm_writers_per_core: self
+                .me_adaptive_floor_max_warm_writers_per_core
+                .load(Ordering::Relaxed) as u16,
+            adaptive_floor_max_active_writers_global: self
+                .me_adaptive_floor_max_active_writers_global
+                .load(Ordering::Relaxed),
+            adaptive_floor_max_warm_writers_global: self
+                .me_adaptive_floor_max_warm_writers_global
+                .load(Ordering::Relaxed),
+            adaptive_floor_cpu_cores_detected: self
+                .me_adaptive_floor_cpu_cores_detected
+                .load(Ordering::Relaxed),
+            adaptive_floor_cpu_cores_effective: self
+                .me_adaptive_floor_cpu_cores_effective
+                .load(Ordering::Relaxed),
+            adaptive_floor_global_cap_raw: self
+                .me_adaptive_floor_global_cap_raw
+                .load(Ordering::Relaxed),
+            adaptive_floor_global_cap_effective: self
+                .me_adaptive_floor_global_cap_effective
+                .load(Ordering::Relaxed),
+            adaptive_floor_target_writers_total: self
+                .me_adaptive_floor_target_writers_total
+                .load(Ordering::Relaxed),
+            adaptive_floor_active_cap_configured: self
+                .me_adaptive_floor_active_cap_configured
+                .load(Ordering::Relaxed),
+            adaptive_floor_active_cap_effective: self
+                .me_adaptive_floor_active_cap_effective
+                .load(Ordering::Relaxed),
+            adaptive_floor_warm_cap_configured: self
+                .me_adaptive_floor_warm_cap_configured
+                .load(Ordering::Relaxed),
+            adaptive_floor_warm_cap_effective: self
+                .me_adaptive_floor_warm_cap_effective
+                .load(Ordering::Relaxed),
+            adaptive_floor_active_writers_current: self
+                .me_adaptive_floor_active_writers_current
+                .load(Ordering::Relaxed),
+            adaptive_floor_warm_writers_current: self
+                .me_adaptive_floor_warm_writers_current
+                .load(Ordering::Relaxed),
             me_keepalive_enabled: self.me_keepalive_enabled,
             me_keepalive_interval_secs: self.me_keepalive_interval.as_secs(),
             me_keepalive_jitter_secs: self.me_keepalive_jitter.as_secs(),
@@ -371,6 +537,24 @@ fn ratio_pct(part: usize, total: usize) -> f64 {
     pct.clamp(0.0, 100.0)
 }
 
+fn extend_signed_endpoints(
+    endpoints_by_dc: &mut BTreeMap<i16, BTreeSet<SocketAddr>>,
+    map: HashMap<i32, Vec<(IpAddr, u16)>>,
+) {
+    for (dc, addrs) in map {
+        if dc == 0 {
+            continue;
+        }
+        let Ok(dc_idx) = i16::try_from(dc) else {
+            continue;
+        };
+        let entry = endpoints_by_dc.entry(dc_idx).or_default();
+        for (ip, port) in addrs {
+            entry.insert(SocketAddr::new(ip, port));
+        }
+    }
+}
+
 fn floor_mode_label(mode: MeFloorMode) -> &'static str {
     match mode {
         MeFloorMode::Static => "static",

src/transport/middle_proxy/pool_writer.rs

@@ -4,6 +4,7 @@ use std::sync::atomic::{AtomicBool, AtomicU8, AtomicU64, Ordering};
 use std::time::{Duration, Instant};
 use std::io::ErrorKind;
 
+use bytes::Bytes;
 use bytes::BytesMut;
 use rand::Rng;
 use tokio::sync::mpsc;
@@ -49,12 +50,18 @@ impl MePool {
         }
     }
 
-    pub(crate) async fn connect_one(self: &Arc<Self>, addr: SocketAddr, rng: &SecureRandom) -> Result<()> {
+    pub(crate) async fn connect_one_for_dc(
+        self: &Arc<Self>,
+        addr: SocketAddr,
+        writer_dc: i32,
+        rng: &SecureRandom,
+    ) -> Result<()> {
         self.connect_one_with_generation_contour(
             addr,
             rng,
             self.current_generation(),
             WriterContour::Active,
+            writer_dc,
         )
         .await
     }
@@ -65,13 +72,56 @@ impl MePool {
         rng: &SecureRandom,
         generation: u64,
         contour: WriterContour,
+        writer_dc: i32,
     ) -> Result<()> {
+        self.connect_one_with_generation_contour_for_dc(addr, rng, generation, contour, writer_dc)
+            .await
+    }
+
+    pub(super) async fn connect_one_with_generation_contour_for_dc(
+        self: &Arc<Self>,
+        addr: SocketAddr,
+        rng: &SecureRandom,
+        generation: u64,
+        contour: WriterContour,
+        writer_dc: i32,
+    ) -> Result<()> {
+        self.connect_one_with_generation_contour_for_dc_with_cap_policy(
+            addr,
+            rng,
+            generation,
+            contour,
+            writer_dc,
+            false,
+        )
+        .await
+    }
+
+    pub(super) async fn connect_one_with_generation_contour_for_dc_with_cap_policy(
+        self: &Arc<Self>,
+        addr: SocketAddr,
+        rng: &SecureRandom,
+        generation: u64,
+        contour: WriterContour,
+        writer_dc: i32,
+        allow_coverage_override: bool,
+    ) -> Result<()> {
+        if !self
+            .can_open_writer_for_contour(contour, allow_coverage_override)
+            .await
+        {
+            return Err(ProxyError::Proxy(format!(
+                "ME {contour:?} writer cap reached"
+            )));
+        }
+
         let secret_len = self.proxy_secret.read().await.secret.len();
         if secret_len < 32 {
             return Err(ProxyError::Proxy("proxy-secret too short for ME auth".into()));
         }
 
-        let (stream, _connect_ms, upstream_egress) = self.connect_tcp(addr).await?;
+        let dc_idx = i16::try_from(writer_dc).ok();
+        let (stream, _connect_ms, upstream_egress) = self.connect_tcp(addr, dc_idx).await?;
         let hs = self.handshake_only(stream, addr, upstream_egress, rng).await?;
 
         let writer_id = self.next_writer_id.fetch_add(1, Ordering::Relaxed);
@@ -80,8 +130,9 @@ impl MePool {
         let degraded = Arc::new(AtomicBool::new(false));
         let draining = Arc::new(AtomicBool::new(false));
         let draining_started_at_epoch_secs = Arc::new(AtomicU64::new(0));
+        let drain_deadline_epoch_secs = Arc::new(AtomicU64::new(0));
         let allow_drain_fallback = Arc::new(AtomicBool::new(false));
-        let (tx, mut rx) = mpsc::channel::<WriterCommand>(4096);
+        let (tx, mut rx) = mpsc::channel::<WriterCommand>(self.writer_cmd_channel_capacity);
         let mut rpc_writer = RpcWriter {
             writer: hs.wr,
             key: hs.write_key,
@@ -111,6 +162,7 @@ impl MePool {
         let writer = MeWriter {
             id: writer_id,
             addr,
+            writer_dc,
             generation,
             contour: contour.clone(),
             created_at: Instant::now(),
@@ -119,6 +171,7 @@ impl MePool {
             degraded: degraded.clone(),
             draining: draining.clone(),
             draining_started_at_epoch_secs: draining_started_at_epoch_secs.clone(),
+            drain_deadline_epoch_secs: drain_deadline_epoch_secs.clone(),
             allow_drain_fallback: allow_drain_fallback.clone(),
         };
         self.writers.write().await.push(writer.clone());
@@ -254,17 +307,47 @@ impl MePool {
                 p.extend_from_slice(&sent_id.to_le_bytes());
                 {
                     let mut tracker = ping_tracker_ping.lock().await;
-                    let before = tracker.len();
-                    tracker.retain(|_, (ts, _)| ts.elapsed() < Duration::from_secs(120));
-                    let expired = before.saturating_sub(tracker.len());
-                    if expired > 0 {
-                        stats_ping.increment_me_keepalive_timeout_by(expired as u64);
+                    let now_epoch_ms = std::time::SystemTime::now()
+                        .duration_since(std::time::UNIX_EPOCH)
+                        .unwrap_or_default()
+                        .as_millis() as u64;
+                    let mut run_cleanup = false;
+                    if let Some(pool) = pool_ping.upgrade() {
+                        let last_cleanup_ms = pool
+                            .ping_tracker_last_cleanup_epoch_ms
+                            .load(Ordering::Relaxed);
+                        if now_epoch_ms.saturating_sub(last_cleanup_ms) >= 30_000
+                            && pool
+                                .ping_tracker_last_cleanup_epoch_ms
+                                .compare_exchange(
+                                    last_cleanup_ms,
+                                    now_epoch_ms,
+                                    Ordering::AcqRel,
+                                    Ordering::Relaxed,
+                                )
+                                .is_ok()
+                        {
+                            run_cleanup = true;
+                        }
+                    }
+
+                    if run_cleanup {
+                        let before = tracker.len();
+                        tracker.retain(|_, (ts, _)| ts.elapsed() < Duration::from_secs(120));
+                        let expired = before.saturating_sub(tracker.len());
+                        if expired > 0 {
+                            stats_ping.increment_me_keepalive_timeout_by(expired as u64);
+                        }
                     }
                     tracker.insert(sent_id, (std::time::Instant::now(), writer_id));
                 }
                 ping_id = ping_id.wrapping_add(1);
                 stats_ping.increment_me_keepalive_sent();
-                if tx_ping.send(WriterCommand::DataAndFlush(p)).await.is_err() {
+                if tx_ping
+                    .send(WriterCommand::DataAndFlush(Bytes::from(p)))
+                    .await
+                    .is_err()
+                {
                     stats_ping.increment_me_keepalive_failed();
                     debug!("ME ping failed, removing dead writer");
                     cancel_ping.cancel();
@@ -338,7 +421,11 @@ impl MePool {
                     meta.proto_flags,
                 );
 
-                if tx_signal.send(WriterCommand::DataAndFlush(payload)).await.is_err() {
+                if tx_signal
+                    .send(WriterCommand::DataAndFlush(payload))
+                    .await
+                    .is_err()
+                {
                     stats_signal.increment_me_rpc_proxy_req_signal_failed_total();
                     let _ = pool.registry.unregister(conn_id).await;
                     cancel_signal.cancel();
@@ -369,7 +456,7 @@ impl MePool {
                 close_payload.extend_from_slice(&conn_id.to_le_bytes());
 
                 if tx_signal
-                    .send(WriterCommand::DataAndFlush(close_payload))
+                    .send(WriterCommand::DataAndFlush(Bytes::from(close_payload)))
                     .await
                     .is_err()
                 {
@@ -404,6 +491,7 @@ impl MePool {
     async fn remove_writer_only(self: &Arc<Self>, writer_id: u64) -> Vec<BoundConn> {
         let mut close_tx: Option<mpsc::Sender<WriterCommand>> = None;
         let mut removed_addr: Option<SocketAddr> = None;
+        let mut removed_dc: Option<i32> = None;
         let mut removed_uptime: Option<Duration> = None;
         let mut trigger_refill = false;
         {
@@ -417,6 +505,7 @@ impl MePool {
                 self.stats.increment_me_writer_removed_total();
                 w.cancel.cancel();
                 removed_addr = Some(w.addr);
+                removed_dc = Some(w.writer_dc);
                 removed_uptime = Some(w.created_at.elapsed());
                 trigger_refill = !was_draining;
                 if trigger_refill {
@@ -431,11 +520,12 @@ impl MePool {
         }
         if trigger_refill
             && let Some(addr) = removed_addr
+            && let Some(writer_dc) = removed_dc
         {
             if let Some(uptime) = removed_uptime {
                 self.maybe_quarantine_flapping_endpoint(addr, uptime).await;
             }
-            self.trigger_immediate_refill(addr);
+            self.trigger_immediate_refill_for_dc(addr, writer_dc);
         }
         self.rtt_stats.lock().await.remove(&writer_id);
         self.registry.writer_lost(writer_id).await
@@ -454,8 +544,14 @@ impl MePool {
                 let already_draining = w.draining.swap(true, Ordering::Relaxed);
                 w.allow_drain_fallback
                     .store(allow_drain_fallback, Ordering::Relaxed);
+                let now_epoch_secs = Self::now_epoch_secs();
                 w.draining_started_at_epoch_secs
-                    .store(Self::now_epoch_secs(), Ordering::Relaxed);
+                    .store(now_epoch_secs, Ordering::Relaxed);
+                let drain_deadline_epoch_secs = timeout
+                    .map(|duration| now_epoch_secs.saturating_add(duration.as_secs()))
+                    .unwrap_or(0);
+                w.drain_deadline_epoch_secs
+                    .store(drain_deadline_epoch_secs, Ordering::Relaxed);
                 if !already_draining {
                     self.stats.increment_pool_drain_active();
                 }
@@ -479,26 +575,6 @@ impl MePool {
             allow_drain_fallback,
             "ME writer marked draining"
         );
-
-        let pool = Arc::downgrade(self);
-        tokio::spawn(async move {
-            let deadline = timeout.map(|t| Instant::now() + t);
-            while let Some(p) = pool.upgrade() {
-                if let Some(deadline_at) = deadline
-                    && Instant::now() >= deadline_at
-                {
-                    warn!(writer_id, "Drain timeout, force-closing");
-                    p.stats.increment_pool_force_close_total();
-                    let _ = p.remove_writer_and_close_clients(writer_id).await;
-                    break;
-                }
-                if p.registry.is_writer_empty(writer_id).await {
-                    let _ = p.remove_writer_only(writer_id).await;
-                    break;
-                }
-                tokio::time::sleep(Duration::from_secs(1)).await;
-            }
-        });
     }
 
     pub(crate) async fn mark_writer_draining(self: &Arc<Self>, writer_id: u64) {

src/transport/middle_proxy/reader.rs

@@ -124,7 +124,7 @@ pub(crate) async fn reader_loop(
                 let data = Bytes::copy_from_slice(&body[12..]);
                 trace!(cid, flags, len = data.len(), "RPC_PROXY_ANS");
 
-                let routed = reg.route(cid, MeResponse::Data { flags, data }).await;
+                let routed = reg.route_nowait(cid, MeResponse::Data { flags, data }).await;
                 if !matches!(routed, RouteResult::Routed) {
                     match routed {
                         RouteResult::NoConn => stats.increment_me_route_drop_no_conn(),
@@ -147,7 +147,7 @@ pub(crate) async fn reader_loop(
                 let cfm = u32::from_le_bytes(body[8..12].try_into().unwrap());
                 trace!(cid, cfm, "RPC_SIMPLE_ACK");
 
-                let routed = reg.route(cid, MeResponse::Ack(cfm)).await;
+                let routed = reg.route_nowait(cid, MeResponse::Ack(cfm)).await;
                 if !matches!(routed, RouteResult::Routed) {
                     match routed {
                         RouteResult::NoConn => stats.increment_me_route_drop_no_conn(),
@@ -181,7 +181,11 @@ pub(crate) async fn reader_loop(
                 let mut pong = Vec::with_capacity(12);
                 pong.extend_from_slice(&RPC_PONG_U32.to_le_bytes());
                 pong.extend_from_slice(&ping_id.to_le_bytes());
-                if tx.send(WriterCommand::DataAndFlush(pong)).await.is_err() {
+                if tx
+                    .send(WriterCommand::DataAndFlush(Bytes::from(pong)))
+                    .await
+                    .is_err()
+                {
                     warn!("PONG send failed");
                     break;
                 }
@@ -222,5 +226,5 @@ async fn send_close_conn(tx: &mpsc::Sender<WriterCommand>, conn_id: u64) {
     p.extend_from_slice(&RPC_CLOSE_CONN_U32.to_le_bytes());
     p.extend_from_slice(&conn_id.to_le_bytes());
 
-    let _ = tx.send(WriterCommand::DataAndFlush(p)).await;
+    let _ = tx.send(WriterCommand::DataAndFlush(Bytes::from(p))).await;
 }

src/transport/middle_proxy/registry.rs

@@ -9,7 +9,6 @@ use tokio::sync::mpsc::error::TrySendError;
 use super::codec::WriterCommand;
 use super::MeResponse;
 
-const ROUTE_CHANNEL_CAPACITY: usize = 4096;
 const ROUTE_BACKPRESSURE_BASE_TIMEOUT_MS: u64 = 25;
 const ROUTE_BACKPRESSURE_HIGH_TIMEOUT_MS: u64 = 120;
 const ROUTE_BACKPRESSURE_HIGH_WATERMARK_PCT: u8 = 80;
@@ -78,6 +77,7 @@ impl RegistryInner {
 pub struct ConnRegistry {
     inner: RwLock<RegistryInner>,
     next_id: AtomicU64,
+    route_channel_capacity: usize,
     route_backpressure_base_timeout_ms: AtomicU64,
     route_backpressure_high_timeout_ms: AtomicU64,
     route_backpressure_high_watermark_pct: AtomicU8,
@@ -91,11 +91,12 @@ impl ConnRegistry {
             .as_secs()
     }
 
-    pub fn new() -> Self {
+    pub fn with_route_channel_capacity(route_channel_capacity: usize) -> Self {
         let start = rand::random::<u64>() | 1;
         Self {
             inner: RwLock::new(RegistryInner::new()),
             next_id: AtomicU64::new(start),
+            route_channel_capacity: route_channel_capacity.max(1),
             route_backpressure_base_timeout_ms: AtomicU64::new(
                 ROUTE_BACKPRESSURE_BASE_TIMEOUT_MS,
             ),
@@ -108,6 +109,11 @@ impl ConnRegistry {
         }
     }
 
+    #[cfg(test)]
+    pub fn new() -> Self {
+        Self::with_route_channel_capacity(4096)
+    }
+
     pub fn update_route_backpressure_policy(
         &self,
         base_timeout_ms: u64,
@@ -127,7 +133,7 @@ impl ConnRegistry {
 
     pub async fn register(&self) -> (u64, mpsc::Receiver<MeResponse>) {
         let id = self.next_id.fetch_add(1, Ordering::Relaxed);
-        let (tx, rx) = mpsc::channel(ROUTE_CHANNEL_CAPACITY);
+        let (tx, rx) = mpsc::channel(self.route_channel_capacity);
         self.inner.write().await.map.insert(id, tx);
         (id, rx)
     }
@@ -179,11 +185,11 @@ impl ConnRegistry {
                     .route_backpressure_high_watermark_pct
                     .load(Ordering::Relaxed)
                     .clamp(1, 100);
-                let used = ROUTE_CHANNEL_CAPACITY.saturating_sub(tx.capacity());
-                let used_pct = if ROUTE_CHANNEL_CAPACITY == 0 {
+                let used = self.route_channel_capacity.saturating_sub(tx.capacity());
+                let used_pct = if self.route_channel_capacity == 0 {
                     100
                 } else {
-                    (used.saturating_mul(100) / ROUTE_CHANNEL_CAPACITY) as u8
+                    (used.saturating_mul(100) / self.route_channel_capacity) as u8
                 };
                 let high_profile = used_pct >= high_watermark_pct;
                 let timeout_ms = if high_profile {
@@ -208,6 +214,23 @@ impl ConnRegistry {
         }
     }
 
+    pub async fn route_nowait(&self, id: u64, resp: MeResponse) -> RouteResult {
+        let tx = {
+            let inner = self.inner.read().await;
+            inner.map.get(&id).cloned()
+        };
+
+        let Some(tx) = tx else {
+            return RouteResult::NoConn;
+        };
+
+        match tx.try_send(resp) {
+            Ok(()) => RouteResult::Routed,
+            Err(TrySendError::Closed(_)) => RouteResult::ChannelClosed,
+            Err(TrySendError::Full(_)) => RouteResult::QueueFullBase,
+        }
+    }
+
     pub async fn bind_writer(
         &self,
         conn_id: u64,
@@ -247,6 +270,20 @@ impl ConnRegistry {
         inner.writer_idle_since_epoch_secs.clone()
     }
 
+    pub async fn writer_idle_since_for_writer_ids(
+        &self,
+        writer_ids: &[u64],
+    ) -> HashMap<u64, u64> {
+        let inner = self.inner.read().await;
+        let mut out = HashMap::<u64, u64>::with_capacity(writer_ids.len());
+        for writer_id in writer_ids {
+            if let Some(idle_since) = inner.writer_idle_since_epoch_secs.get(writer_id).copied() {
+                out.insert(*writer_id, idle_since);
+            }
+        }
+        out
+    }
+
     pub(super) async fn writer_activity_snapshot(&self) -> WriterActivitySnapshot {
         let inner = self.inner.read().await;
         let mut bound_clients_by_writer = HashMap::<u64, usize>::new();
@@ -256,13 +293,12 @@ impl ConnRegistry {
             bound_clients_by_writer.insert(*writer_id, conn_ids.len());
         }
         for conn_meta in inner.meta.values() {
-            let dc_u16 = conn_meta.target_dc.unsigned_abs();
-            if dc_u16 == 0 {
+            if conn_meta.target_dc == 0 {
                 continue;
             }
-            if let Ok(dc) = i16::try_from(dc_u16) {
-                *active_sessions_by_target_dc.entry(dc).or_insert(0) += 1;
-            }
+            *active_sessions_by_target_dc
+                .entry(conn_meta.target_dc)
+                .or_insert(0) += 1;
         }
 
         WriterActivitySnapshot {
@@ -278,6 +314,11 @@ impl ConnRegistry {
         Some(ConnWriter { writer_id, tx: writer })
     }
 
+    pub async fn active_conn_ids(&self) -> Vec<u64> {
+        let inner = self.inner.read().await;
+        inner.writer_for_conn.keys().copied().collect()
+    }
+
     pub async fn writer_lost(&self, writer_id: u64) -> Vec<BoundConn> {
         let mut inner = self.inner.write().await;
         inner.writers.remove(&writer_id);
@@ -380,7 +421,8 @@ mod tests {
         let snapshot = registry.writer_activity_snapshot().await;
         assert_eq!(snapshot.bound_clients_by_writer.get(&10), Some(&2));
         assert_eq!(snapshot.bound_clients_by_writer.get(&20), Some(&1));
-        assert_eq!(snapshot.active_sessions_by_target_dc.get(&2), Some(&2));
+        assert_eq!(snapshot.active_sessions_by_target_dc.get(&2), Some(&1));
+        assert_eq!(snapshot.active_sessions_by_target_dc.get(&-2), Some(&1));
         assert_eq!(snapshot.active_sessions_by_target_dc.get(&4), Some(&1));
     }
 }

src/transport/middle_proxy/send.rs

@@ -1,16 +1,18 @@
 use std::cmp::Reverse;
-use std::collections::HashMap;
+use std::collections::{HashMap, HashSet};
 use std::net::SocketAddr;
 use std::sync::Arc;
 use std::sync::atomic::Ordering;
-use std::time::Duration;
+use std::time::{Duration, Instant};
 
+use bytes::Bytes;
 use tokio::sync::mpsc::error::TrySendError;
 use tracing::{debug, warn};
 
+use crate::config::MeRouteNoWriterMode;
 use crate::error::{ProxyError, Result};
 use crate::network::IpFamily;
-use crate::protocol::constants::RPC_CLOSE_EXT_U32;
+use crate::protocol::constants::{RPC_CLOSE_CONN_U32, RPC_CLOSE_EXT_U32};
 
 use super::MePool;
 use super::codec::WriterCommand;
@@ -21,6 +23,7 @@ use super::registry::ConnMeta;
 
 const IDLE_WRITER_PENALTY_MID_SECS: u64 = 45;
 const IDLE_WRITER_PENALTY_HIGH_SECS: u64 = 55;
+const HYBRID_GLOBAL_BURST_PERIOD_ROUNDS: u32 = 4;
 
 impl MePool {
     /// Send RPC_PROXY_REQ. `tag_override`: per-user ad_tag (from access.user_ad_tags); if None, uses pool default.
@@ -49,7 +52,18 @@ impl MePool {
             our_addr,
             proto_flags,
         };
-        let mut emergency_attempts = 0;
+        let no_writer_mode =
+            MeRouteNoWriterMode::from_u8(self.me_route_no_writer_mode.load(Ordering::Relaxed));
+        let (routed_dc, unknown_target_dc) = self
+            .resolve_target_dc_for_routing(target_dc as i32)
+            .await;
+        let mut no_writer_deadline: Option<Instant> = None;
+        let mut emergency_attempts = 0u32;
+        let mut async_recovery_triggered = false;
+        let mut hybrid_recovery_round = 0u32;
+        let mut hybrid_last_recovery_at: Option<Instant> = None;
+        let hybrid_wait_step = self.me_route_no_writer_wait.max(Duration::from_millis(50));
+        let mut hybrid_wait_current = hybrid_wait_step;
 
         loop {
             if let Some(current) = self.registry.get_writer(conn_id).await {
@@ -74,89 +88,185 @@ impl MePool {
             let mut writers_snapshot = {
                 let ws = self.writers.read().await;
                 if ws.is_empty() {
-                    // Create waiter before recovery attempts so notify_one permits are not missed.
-                    let waiter = self.writer_available.notified();
                     drop(ws);
-                    for family in self.family_order() {
-                        let map = match family {
-                            IpFamily::V4 => self.proxy_map_v4.read().await.clone(),
-                            IpFamily::V6 => self.proxy_map_v6.read().await.clone(),
-                        };
-                        for (_dc, addrs) in map.iter() {
-                            for (ip, port) in addrs {
-                                let addr = SocketAddr::new(*ip, *port);
-                                if self.connect_one(addr, self.rng.as_ref()).await.is_ok() {
-                                    self.writer_available.notify_one();
-                                    break;
+                    match no_writer_mode {
+                        MeRouteNoWriterMode::AsyncRecoveryFailfast => {
+                            let deadline = *no_writer_deadline.get_or_insert_with(|| {
+                                Instant::now() + self.me_route_no_writer_wait
+                            });
+                            if !async_recovery_triggered && !unknown_target_dc {
+                                let triggered =
+                                    self.trigger_async_recovery_for_target_dc(routed_dc).await;
+                                if !triggered {
+                                    self.trigger_async_recovery_global().await;
+                                }
+                                async_recovery_triggered = true;
+                            }
+                            if self.wait_for_writer_until(deadline).await {
+                                continue;
+                            }
+                            self.stats.increment_me_no_writer_failfast_total();
+                            return Err(ProxyError::Proxy(
+                                "No ME writer available in failfast window".into(),
+                            ));
+                        }
+                        MeRouteNoWriterMode::InlineRecoveryLegacy => {
+                            self.stats.increment_me_inline_recovery_total();
+                            if !unknown_target_dc {
+                                for _ in 0..self.me_route_inline_recovery_attempts.max(1) {
+                                    for family in self.family_order() {
+                                        let map = match family {
+                                            IpFamily::V4 => self.proxy_map_v4.read().await.clone(),
+                                            IpFamily::V6 => self.proxy_map_v6.read().await.clone(),
+                                        };
+                                        for (dc, addrs) in &map {
+                                            for (ip, port) in addrs {
+                                                let addr = SocketAddr::new(*ip, *port);
+                                                let _ = self
+                                                    .connect_one_for_dc(addr, *dc, self.rng.as_ref())
+                                                    .await;
+                                            }
+                                        }
+                                    }
+                                    if !self.writers.read().await.is_empty() {
+                                        break;
+                                    }
                                 }
                             }
-                        }
-                    }
-                    if !self.writers.read().await.is_empty() {
-                        continue;
-                    }
-                    if tokio::time::timeout(Duration::from_secs(3), waiter).await.is_err() {
-                        if !self.writers.read().await.is_empty() {
+
+                            if !self.writers.read().await.is_empty() {
+                                continue;
+                            }
+                            let deadline = *no_writer_deadline
+                                .get_or_insert_with(|| Instant::now() + self.me_route_inline_recovery_wait);
+                            if !self.wait_for_writer_until(deadline).await {
+                                if !self.writers.read().await.is_empty() {
+                                    continue;
+                                }
+                                self.stats.increment_me_no_writer_failfast_total();
+                                return Err(ProxyError::Proxy(
+                                    "All ME connections dead (legacy wait timeout)".into(),
+                                ));
+                            }
+                            continue;
+                        }
+                        MeRouteNoWriterMode::HybridAsyncPersistent => {
+                            if !unknown_target_dc {
+                                self.maybe_trigger_hybrid_recovery(
+                                    routed_dc,
+                                    &mut hybrid_recovery_round,
+                                    &mut hybrid_last_recovery_at,
+                                    hybrid_wait_current,
+                                )
+                                .await;
+                            }
+                            let deadline = Instant::now() + hybrid_wait_current;
+                            let _ = self.wait_for_writer_until(deadline).await;
+                            hybrid_wait_current =
+                                (hybrid_wait_current.saturating_mul(2))
+                                    .min(Duration::from_millis(400));
                             continue;
                         }
-                        return Err(ProxyError::Proxy("All ME connections dead (waited 3s)".into()));
                     }
-                    continue;
                 }
                 ws.clone()
             };
 
             let mut candidate_indices = self
-                .candidate_indices_for_dc(&writers_snapshot, target_dc, false)
+                .candidate_indices_for_dc(&writers_snapshot, routed_dc, false)
                 .await;
             if candidate_indices.is_empty() {
                 candidate_indices = self
-                    .candidate_indices_for_dc(&writers_snapshot, target_dc, true)
+                    .candidate_indices_for_dc(&writers_snapshot, routed_dc, true)
                     .await;
             }
             if candidate_indices.is_empty() {
-                // Emergency connect-on-demand
-                if emergency_attempts >= 3 {
-                    return Err(ProxyError::Proxy("No ME writers available for target DC".into()));
-                }
-                emergency_attempts += 1;
-                for family in self.family_order() {
-                    let map_guard = match family {
-                        IpFamily::V4 => self.proxy_map_v4.read().await,
-                        IpFamily::V6 => self.proxy_map_v6.read().await,
-                    };
-                    if let Some(addrs) = map_guard.get(&(target_dc as i32)) {
-                        let mut shuffled = addrs.clone();
-                        shuffled.shuffle(&mut rand::rng());
-                        drop(map_guard);
-                        for (ip, port) in shuffled {
-                            let addr = SocketAddr::new(ip, port);
-                            if self.connect_one(addr, self.rng.as_ref()).await.is_ok() {
+                match no_writer_mode {
+                    MeRouteNoWriterMode::AsyncRecoveryFailfast => {
+                        let deadline = *no_writer_deadline.get_or_insert_with(|| {
+                            Instant::now() + self.me_route_no_writer_wait
+                        });
+                        if !async_recovery_triggered && !unknown_target_dc {
+                            let triggered = self.trigger_async_recovery_for_target_dc(routed_dc).await;
+                            if !triggered {
+                                self.trigger_async_recovery_global().await;
+                            }
+                            async_recovery_triggered = true;
+                        }
+                        if self.wait_for_candidate_until(routed_dc, deadline).await {
+                            continue;
+                        }
+                        self.stats.increment_me_no_writer_failfast_total();
+                        return Err(ProxyError::Proxy(
+                            "No ME writers available for target DC in failfast window".into(),
+                        ));
+                    }
+                    MeRouteNoWriterMode::InlineRecoveryLegacy => {
+                        self.stats.increment_me_inline_recovery_total();
+                        if unknown_target_dc {
+                            let deadline = *no_writer_deadline
+                                .get_or_insert_with(|| Instant::now() + self.me_route_inline_recovery_wait);
+                            if self.wait_for_candidate_until(routed_dc, deadline).await {
+                                continue;
+                            }
+                            self.stats.increment_me_no_writer_failfast_total();
+                            return Err(ProxyError::Proxy("No ME writers available for target DC".into()));
+                        }
+                        if emergency_attempts >= self.me_route_inline_recovery_attempts.max(1) {
+                            self.stats.increment_me_no_writer_failfast_total();
+                            return Err(ProxyError::Proxy("No ME writers available for target DC".into()));
+                        }
+                        emergency_attempts += 1;
+                        let mut endpoints = self.endpoint_candidates_for_target_dc(routed_dc).await;
+                        endpoints.shuffle(&mut rand::rng());
+                        for addr in endpoints {
+                            if self.connect_one_for_dc(addr, routed_dc, self.rng.as_ref()).await.is_ok() {
                                 break;
                             }
                         }
-                        tokio::time::sleep(Duration::from_millis(100 * emergency_attempts)).await;
+                        tokio::time::sleep(Duration::from_millis(100 * emergency_attempts as u64)).await;
                         let ws2 = self.writers.read().await;
                         writers_snapshot = ws2.clone();
                         drop(ws2);
                         candidate_indices = self
-                            .candidate_indices_for_dc(&writers_snapshot, target_dc, false)
+                            .candidate_indices_for_dc(&writers_snapshot, routed_dc, false)
                             .await;
                         if candidate_indices.is_empty() {
                             candidate_indices = self
-                                .candidate_indices_for_dc(&writers_snapshot, target_dc, true)
+                                .candidate_indices_for_dc(&writers_snapshot, routed_dc, true)
                                 .await;
                         }
-                        if !candidate_indices.is_empty() {
-                            break;
+                        if candidate_indices.is_empty() {
+                            return Err(ProxyError::Proxy("No ME writers available for target DC".into()));
                         }
                     }
-                }
-                if candidate_indices.is_empty() {
-                    return Err(ProxyError::Proxy("No ME writers available for target DC".into()));
+                    MeRouteNoWriterMode::HybridAsyncPersistent => {
+                        if !unknown_target_dc {
+                            self.maybe_trigger_hybrid_recovery(
+                                routed_dc,
+                                &mut hybrid_recovery_round,
+                                &mut hybrid_last_recovery_at,
+                                hybrid_wait_current,
+                            )
+                            .await;
+                        }
+                        let deadline = Instant::now() + hybrid_wait_current;
+                        let _ = self.wait_for_candidate_until(routed_dc, deadline).await;
+                        hybrid_wait_current = (hybrid_wait_current.saturating_mul(2))
+                            .min(Duration::from_millis(400));
+                        continue;
+                    }
                 }
             }
-            let writer_idle_since = self.registry.writer_idle_since_snapshot().await;
+            hybrid_wait_current = hybrid_wait_step;
+            let writer_ids: Vec<u64> = candidate_indices
+                .iter()
+                .map(|idx| writers_snapshot[*idx].id)
+                .collect();
+            let writer_idle_since = self
+                .registry
+                .writer_idle_since_for_writer_ids(&writer_ids)
+                .await;
             let now_epoch_secs = Self::now_epoch_secs();
 
             if self.me_deterministic_writer_sort.load(Ordering::Relaxed) {
@@ -275,12 +385,136 @@ impl MePool {
         }
     }
 
+    async fn wait_for_writer_until(&self, deadline: Instant) -> bool {
+        let waiter = self.writer_available.notified();
+        if !self.writers.read().await.is_empty() {
+            return true;
+        }
+        let now = Instant::now();
+        if now >= deadline {
+            return !self.writers.read().await.is_empty();
+        }
+        let timeout = deadline.saturating_duration_since(now);
+        if tokio::time::timeout(timeout, waiter).await.is_ok() {
+            return true;
+        }
+        !self.writers.read().await.is_empty()
+    }
+
+    async fn wait_for_candidate_until(&self, routed_dc: i32, deadline: Instant) -> bool {
+        loop {
+            if self.has_candidate_for_target_dc(routed_dc).await {
+                return true;
+            }
+
+            let now = Instant::now();
+            if now >= deadline {
+                return self.has_candidate_for_target_dc(routed_dc).await;
+            }
+
+            let waiter = self.writer_available.notified();
+            if self.has_candidate_for_target_dc(routed_dc).await {
+                return true;
+            }
+            let remaining = deadline.saturating_duration_since(Instant::now());
+            if remaining.is_zero() {
+                return self.has_candidate_for_target_dc(routed_dc).await;
+            }
+            if tokio::time::timeout(remaining, waiter).await.is_err() {
+                return self.has_candidate_for_target_dc(routed_dc).await;
+            }
+        }
+    }
+
+    async fn has_candidate_for_target_dc(&self, routed_dc: i32) -> bool {
+        let writers_snapshot = {
+            let ws = self.writers.read().await;
+            if ws.is_empty() {
+                return false;
+            }
+            ws.clone()
+        };
+        let mut candidate_indices = self
+            .candidate_indices_for_dc(&writers_snapshot, routed_dc, false)
+            .await;
+        if candidate_indices.is_empty() {
+            candidate_indices = self
+                .candidate_indices_for_dc(&writers_snapshot, routed_dc, true)
+                .await;
+        }
+        !candidate_indices.is_empty()
+    }
+
+    async fn trigger_async_recovery_for_target_dc(self: &Arc<Self>, routed_dc: i32) -> bool {
+        let endpoints = self.endpoint_candidates_for_target_dc(routed_dc).await;
+        if endpoints.is_empty() {
+            return false;
+        }
+        self.stats.increment_me_async_recovery_trigger_total();
+        for addr in endpoints.into_iter().take(8) {
+            self.trigger_immediate_refill_for_dc(addr, routed_dc);
+        }
+        true
+    }
+
+    async fn trigger_async_recovery_global(self: &Arc<Self>) {
+        self.stats.increment_me_async_recovery_trigger_total();
+        let mut seen = HashSet::<(i32, SocketAddr)>::new();
+        for family in self.family_order() {
+            let map_guard = match family {
+                IpFamily::V4 => self.proxy_map_v4.read().await,
+                IpFamily::V6 => self.proxy_map_v6.read().await,
+            };
+            for (dc, addrs) in map_guard.iter() {
+                for (ip, port) in addrs {
+                    let addr = SocketAddr::new(*ip, *port);
+                    if seen.insert((*dc, addr)) {
+                        self.trigger_immediate_refill_for_dc(addr, *dc);
+                    }
+                    if seen.len() >= 8 {
+                        return;
+                    }
+                }
+            }
+        }
+    }
+
+    async fn endpoint_candidates_for_target_dc(&self, routed_dc: i32) -> Vec<SocketAddr> {
+        self.preferred_endpoints_for_dc(routed_dc).await
+    }
+
+    async fn maybe_trigger_hybrid_recovery(
+        self: &Arc<Self>,
+        routed_dc: i32,
+        hybrid_recovery_round: &mut u32,
+        hybrid_last_recovery_at: &mut Option<Instant>,
+        hybrid_wait_step: Duration,
+    ) {
+        if let Some(last) = *hybrid_last_recovery_at
+            && last.elapsed() < hybrid_wait_step
+        {
+            return;
+        }
+
+        let round = *hybrid_recovery_round;
+        let target_triggered = self.trigger_async_recovery_for_target_dc(routed_dc).await;
+        if !target_triggered || round % HYBRID_GLOBAL_BURST_PERIOD_ROUNDS == 0 {
+            self.trigger_async_recovery_global().await;
+        }
+        *hybrid_recovery_round = round.saturating_add(1);
+        *hybrid_last_recovery_at = Some(Instant::now());
+    }
+
     pub async fn send_close(self: &Arc<Self>, conn_id: u64) -> Result<()> {
         if let Some(w) = self.registry.get_writer(conn_id).await {
             let mut p = Vec::with_capacity(12);
             p.extend_from_slice(&RPC_CLOSE_EXT_U32.to_le_bytes());
             p.extend_from_slice(&conn_id.to_le_bytes());
-            if w.tx.send(WriterCommand::DataAndFlush(p)).await.is_err() {
+            if w.tx
+                .send(WriterCommand::DataAndFlush(Bytes::from(p)))
+                .await
+                .is_err()
+            {
                 debug!("ME close write failed");
                 self.remove_writer_and_close_clients(w.writer_id).await;
             }
@@ -292,6 +526,37 @@ impl MePool {
         Ok(())
     }
 
+    pub async fn send_close_conn(self: &Arc<Self>, conn_id: u64) -> Result<()> {
+        if let Some(w) = self.registry.get_writer(conn_id).await {
+            let mut p = Vec::with_capacity(12);
+            p.extend_from_slice(&RPC_CLOSE_CONN_U32.to_le_bytes());
+            p.extend_from_slice(&conn_id.to_le_bytes());
+            match w.tx.try_send(WriterCommand::DataAndFlush(Bytes::from(p))) {
+                Ok(()) => {}
+                Err(TrySendError::Full(cmd)) => {
+                    let _ = tokio::time::timeout(Duration::from_millis(50), w.tx.send(cmd)).await;
+                }
+                Err(TrySendError::Closed(_)) => {
+                    debug!(conn_id, "ME close_conn skipped: writer channel closed");
+                }
+            }
+        } else {
+            debug!(conn_id, "ME close_conn skipped (writer missing)");
+        }
+
+        self.registry.unregister(conn_id).await;
+        Ok(())
+    }
+
+    pub async fn shutdown_send_close_conn_all(self: &Arc<Self>) -> usize {
+        let conn_ids = self.registry.active_conn_ids().await;
+        let total = conn_ids.len();
+        for conn_id in conn_ids {
+            let _ = self.send_close_conn(conn_id).await;
+        }
+        total
+    }
+
     pub fn connection_count(&self) -> usize {
         self.conn_count.load(Ordering::Relaxed)
     }
@@ -299,53 +564,12 @@ impl MePool {
     pub(super) async fn candidate_indices_for_dc(
         &self,
         writers: &[super::pool::MeWriter],
-        target_dc: i16,
+        routed_dc: i32,
         include_warm: bool,
     ) -> Vec<usize> {
-        let key = target_dc as i32;
-        let mut preferred = Vec::<SocketAddr>::new();
-
-        for family in self.family_order() {
-            let map_guard = match family {
-                IpFamily::V4 => self.proxy_map_v4.read().await,
-                IpFamily::V6 => self.proxy_map_v6.read().await,
-            };
-
-            if let Some(v) = map_guard.get(&key) {
-                preferred.extend(v.iter().map(|(ip, port)| SocketAddr::new(*ip, *port)));
-            }
-            if preferred.is_empty() {
-                let abs = key.abs();
-                if let Some(v) = map_guard.get(&abs) {
-                    preferred.extend(v.iter().map(|(ip, port)| SocketAddr::new(*ip, *port)));
-                }
-            }
-            if preferred.is_empty() {
-                let abs = key.abs();
-                if let Some(v) = map_guard.get(&-abs) {
-                    preferred.extend(v.iter().map(|(ip, port)| SocketAddr::new(*ip, *port)));
-                }
-            }
-            if preferred.is_empty() {
-                let def = self.default_dc.load(Ordering::Relaxed);
-                if def != 0
-                    && let Some(v) = map_guard.get(&def)
-                {
-                    preferred.extend(v.iter().map(|(ip, port)| SocketAddr::new(*ip, *port)));
-                }
-            }
-
-            drop(map_guard);
-
-            if !preferred.is_empty() && !self.decision.effective_multipath {
-                break;
-            }
-        }
-
+        let preferred = self.preferred_endpoints_for_dc(routed_dc).await;
         if preferred.is_empty() {
-            return (0..writers.len())
-                .filter(|i| self.writer_eligible_for_selection(&writers[*i], include_warm))
-                .collect();
+            return Vec::new();
         }
 
         let mut out = Vec::new();
@@ -353,15 +577,10 @@ impl MePool {
             if !self.writer_eligible_for_selection(w, include_warm) {
                 continue;
             }
-            if preferred.contains(&w.addr) {
+            if w.writer_dc == routed_dc && preferred.iter().any(|endpoint| *endpoint == w.addr) {
                 out.push(idx);
             }
         }
-        if out.is_empty() {
-            return (0..writers.len())
-                .filter(|i| self.writer_eligible_for_selection(&writers[*i], include_warm))
-                .collect();
-        }
         out
     }
 

src/transport/middle_proxy/wire.rs

@@ -1,4 +1,5 @@
 use std::net::{IpAddr, Ipv4Addr, SocketAddr};
+use bytes::Bytes;
 
 use crate::protocol::constants::*;
 
@@ -48,7 +49,7 @@ pub(crate) fn build_proxy_req_payload(
     data: &[u8],
     proxy_tag: Option<&[u8]>,
     proto_flags: u32,
-) -> Vec<u8> {
+) -> Bytes {
     let mut b = Vec::with_capacity(128 + data.len());
 
     b.extend_from_slice(&RPC_PROXY_REQ_U32.to_le_bytes());
@@ -85,7 +86,7 @@ pub(crate) fn build_proxy_req_payload(
     }
 
     b.extend_from_slice(data);
-    b
+    Bytes::from(b)
 }
 
 pub fn proto_flags_for_tag(tag: crate::protocol::constants::ProtoTag, has_proxy_tag: bool) -> u32 {

src/transport/upstream.rs

@@ -7,7 +7,7 @@
 use std::collections::{BTreeSet, HashMap};
 use std::net::{SocketAddr, IpAddr};
 use std::sync::Arc;
-use std::sync::atomic::{AtomicUsize, Ordering};
+use std::sync::atomic::{AtomicU64, AtomicUsize, Ordering};
 use std::time::Duration;
 use tokio::net::TcpStream;
 use tokio::sync::RwLock;
@@ -165,6 +165,52 @@ pub enum UpstreamRouteKind {
     Socks5,
 }
 
+#[derive(Debug, Clone)]
+pub struct UpstreamApiDcSnapshot {
+    pub dc: i16,
+    pub latency_ema_ms: Option<f64>,
+    pub ip_preference: IpPreference,
+}
+
+#[derive(Debug, Clone)]
+pub struct UpstreamApiItemSnapshot {
+    pub upstream_id: usize,
+    pub route_kind: UpstreamRouteKind,
+    pub address: String,
+    pub weight: u16,
+    pub scopes: String,
+    pub healthy: bool,
+    pub fails: u32,
+    pub last_check_age_secs: u64,
+    pub effective_latency_ms: Option<f64>,
+    pub dc: Vec<UpstreamApiDcSnapshot>,
+}
+
+#[derive(Debug, Clone, Default)]
+pub struct UpstreamApiSummarySnapshot {
+    pub configured_total: usize,
+    pub healthy_total: usize,
+    pub unhealthy_total: usize,
+    pub direct_total: usize,
+    pub socks4_total: usize,
+    pub socks5_total: usize,
+}
+
+#[derive(Debug, Clone)]
+pub struct UpstreamApiSnapshot {
+    pub summary: UpstreamApiSummarySnapshot,
+    pub upstreams: Vec<UpstreamApiItemSnapshot>,
+}
+
+#[derive(Debug, Clone, Copy)]
+pub struct UpstreamApiPolicySnapshot {
+    pub connect_retry_attempts: u32,
+    pub connect_retry_backoff_ms: u64,
+    pub connect_budget_ms: u64,
+    pub unhealthy_fail_threshold: u32,
+    pub connect_failfast_hard_errors: bool,
+}
+
 #[derive(Debug, Clone, Copy, PartialEq, Eq)]
 pub struct UpstreamEgressInfo {
     pub route_kind: UpstreamRouteKind,
@@ -188,8 +234,11 @@ pub struct UpstreamManager {
     upstreams: Arc<RwLock<Vec<UpstreamState>>>,
     connect_retry_attempts: u32,
     connect_retry_backoff: Duration,
+    connect_budget: Duration,
     unhealthy_fail_threshold: u32,
     connect_failfast_hard_errors: bool,
+    no_upstreams_warn_epoch_ms: Arc<AtomicU64>,
+    no_healthy_warn_epoch_ms: Arc<AtomicU64>,
     stats: Arc<Stats>,
 }
 
@@ -198,6 +247,7 @@ impl UpstreamManager {
         configs: Vec<UpstreamConfig>,
         connect_retry_attempts: u32,
         connect_retry_backoff_ms: u64,
+        connect_budget_ms: u64,
         unhealthy_fail_threshold: u32,
         connect_failfast_hard_errors: bool,
         stats: Arc<Stats>,
@@ -211,12 +261,106 @@ impl UpstreamManager {
             upstreams: Arc::new(RwLock::new(states)),
             connect_retry_attempts: connect_retry_attempts.max(1),
             connect_retry_backoff: Duration::from_millis(connect_retry_backoff_ms),
+            connect_budget: Duration::from_millis(connect_budget_ms.max(1)),
             unhealthy_fail_threshold: unhealthy_fail_threshold.max(1),
             connect_failfast_hard_errors,
+            no_upstreams_warn_epoch_ms: Arc::new(AtomicU64::new(0)),
+            no_healthy_warn_epoch_ms: Arc::new(AtomicU64::new(0)),
             stats,
         }
     }
 
+    fn now_epoch_ms() -> u64 {
+        std::time::SystemTime::now()
+            .duration_since(std::time::UNIX_EPOCH)
+            .unwrap_or_default()
+            .as_millis() as u64
+    }
+
+    fn should_emit_warn(last_epoch_ms: &AtomicU64, cooldown_ms: u64) -> bool {
+        let now_epoch_ms = Self::now_epoch_ms();
+        let previous_epoch_ms = last_epoch_ms.load(Ordering::Relaxed);
+        if now_epoch_ms.saturating_sub(previous_epoch_ms) < cooldown_ms {
+            return false;
+        }
+        last_epoch_ms
+            .compare_exchange(
+                previous_epoch_ms,
+                now_epoch_ms,
+                Ordering::AcqRel,
+                Ordering::Relaxed,
+            )
+            .is_ok()
+    }
+
+    pub fn try_api_snapshot(&self) -> Option<UpstreamApiSnapshot> {
+        let guard = self.upstreams.try_read().ok()?;
+        let now = std::time::Instant::now();
+
+        let mut summary = UpstreamApiSummarySnapshot {
+            configured_total: guard.len(),
+            ..UpstreamApiSummarySnapshot::default()
+        };
+        let mut upstreams = Vec::with_capacity(guard.len());
+
+        for (idx, upstream) in guard.iter().enumerate() {
+            if upstream.healthy {
+                summary.healthy_total += 1;
+            } else {
+                summary.unhealthy_total += 1;
+            }
+
+            let (route_kind, address) = match &upstream.config.upstream_type {
+                UpstreamType::Direct { .. } => {
+                    summary.direct_total += 1;
+                    (UpstreamRouteKind::Direct, "direct".to_string())
+                }
+                UpstreamType::Socks4 { address, .. } => {
+                    summary.socks4_total += 1;
+                    (UpstreamRouteKind::Socks4, address.clone())
+                }
+                UpstreamType::Socks5 { address, .. } => {
+                    summary.socks5_total += 1;
+                    (UpstreamRouteKind::Socks5, address.clone())
+                }
+            };
+
+            let mut dc = Vec::with_capacity(NUM_DCS);
+            for dc_idx in 0..NUM_DCS {
+                dc.push(UpstreamApiDcSnapshot {
+                    dc: (dc_idx + 1) as i16,
+                    latency_ema_ms: upstream.dc_latency[dc_idx].get(),
+                    ip_preference: upstream.dc_ip_pref[dc_idx],
+                });
+            }
+
+            upstreams.push(UpstreamApiItemSnapshot {
+                upstream_id: idx,
+                route_kind,
+                address,
+                weight: upstream.config.weight,
+                scopes: upstream.config.scopes.clone(),
+                healthy: upstream.healthy,
+                fails: upstream.fails,
+                last_check_age_secs: now.saturating_duration_since(upstream.last_check).as_secs(),
+                effective_latency_ms: upstream.effective_latency(None),
+                dc,
+            });
+        }
+
+        Some(UpstreamApiSnapshot { summary, upstreams })
+    }
+
+    pub fn api_policy_snapshot(&self) -> UpstreamApiPolicySnapshot {
+        UpstreamApiPolicySnapshot {
+            connect_retry_attempts: self.connect_retry_attempts,
+            connect_retry_backoff_ms: self.connect_retry_backoff.as_millis() as u64,
+            connect_budget_ms: self.connect_budget.as_millis() as u64,
+            unhealthy_fail_threshold: self.unhealthy_fail_threshold,
+            connect_failfast_hard_errors: self.connect_failfast_hard_errors,
+        }
+    }
+
     #[cfg(unix)]
     fn resolve_interface_addrs(name: &str, want_ipv6: bool) -> Vec<IpAddr> {
         use nix::ifaddrs::getifaddrs;
@@ -416,12 +560,22 @@ impl UpstreamManager {
             .collect();
 
         if filtered_upstreams.is_empty() {
-            warn!(scope = scope, "No upstreams available! Using first (direct?)");
+            if Self::should_emit_warn(
+                self.no_upstreams_warn_epoch_ms.as_ref(),
+                5_000,
+            ) {
+                warn!(scope = scope, "No upstreams available! Using first (direct?)");
+            }
             return None;
         }
 
         if healthy.is_empty() {
-            warn!(scope = scope, "No healthy upstreams available! Using random.");
+            if Self::should_emit_warn(
+                self.no_healthy_warn_epoch_ms.as_ref(),
+                5_000,
+            ) {
+                warn!(scope = scope, "No healthy upstreams available! Using random.");
+            }
             return Some(filtered_upstreams[rand::rng().gen_range(0..filtered_upstreams.len())]);
         }
 
@@ -498,11 +652,27 @@ impl UpstreamManager {
         let mut last_error: Option<ProxyError> = None;
         let mut attempts_used = 0u32;
         for attempt in 1..=self.connect_retry_attempts {
+            let elapsed = connect_started_at.elapsed();
+            if elapsed >= self.connect_budget {
+                last_error = Some(ProxyError::ConnectionTimeout {
+                    addr: target.to_string(),
+                });
+                break;
+            }
+            let remaining_budget = self.connect_budget.saturating_sub(elapsed);
+            let attempt_timeout = Duration::from_secs(DIRECT_CONNECT_TIMEOUT_SECS)
+                .min(remaining_budget);
+            if attempt_timeout.is_zero() {
+                last_error = Some(ProxyError::ConnectionTimeout {
+                    addr: target.to_string(),
+                });
+                break;
+            }
             attempts_used = attempt;
             self.stats.increment_upstream_connect_attempt_total();
             let start = Instant::now();
             match self
-                .connect_via_upstream(&upstream, target, bind_rr.clone())
+                .connect_via_upstream(&upstream, target, bind_rr.clone(), attempt_timeout)
                 .await
             {
                 Ok((stream, egress)) => {
@@ -612,6 +782,7 @@ impl UpstreamManager {
         config: &UpstreamConfig,
         target: SocketAddr,
         bind_rr: Option<Arc<AtomicUsize>>,
+        connect_timeout: Duration,
     ) -> Result<(TcpStream, UpstreamEgressInfo)> {
         match &config.upstream_type {
             UpstreamType::Direct { interface, bind_addresses } => {
@@ -640,7 +811,6 @@ impl UpstreamManager {
                 let std_stream: std::net::TcpStream = socket.into();
                 let stream = TcpStream::from_std(std_stream)?;
 
-                let connect_timeout = Duration::from_secs(DIRECT_CONNECT_TIMEOUT_SECS);
                 match tokio::time::timeout(connect_timeout, stream.writable()).await {
                     Ok(Ok(())) => {}
                     Ok(Err(e)) => return Err(ProxyError::Io(e)),
@@ -667,7 +837,6 @@ impl UpstreamManager {
                 ))
             },
             UpstreamType::Socks4 { address, interface, user_id } => {
-                let connect_timeout = Duration::from_secs(DIRECT_CONNECT_TIMEOUT_SECS);
                 // Try to parse as SocketAddr first (IP:port), otherwise treat as hostname:port
                 let mut stream = if let Ok(proxy_addr) = address.parse::<SocketAddr>() {
                     // IP:port format - use socket with optional interface binding
@@ -746,7 +915,6 @@ impl UpstreamManager {
                 ))
             },
             UpstreamType::Socks5 { address, interface, username, password } => {
-                let connect_timeout = Duration::from_secs(DIRECT_CONNECT_TIMEOUT_SECS);
                 // Try to parse as SocketAddr first (IP:port), otherwise treat as hostname:port
                 let mut stream = if let Ok(proxy_addr) = address.parse::<SocketAddr>() {
                     // IP:port format - use socket with optional interface binding
@@ -1070,7 +1238,14 @@ impl UpstreamManager {
         target: SocketAddr,
     ) -> Result<f64> {
         let start = Instant::now();
-        let _ = self.connect_via_upstream(config, target, bind_rr).await?;
+        let _ = self
+            .connect_via_upstream(
+                config,
+                target,
+                bind_rr,
+                Duration::from_secs(DC_PING_TIMEOUT_SECS),
+            )
+            .await?;
         Ok(start.elapsed().as_secs_f64() * 1000.0)
     }
 
@@ -1242,7 +1417,12 @@ impl UpstreamManager {
                             let start = Instant::now();
                             let result = tokio::time::timeout(
                                 Duration::from_secs(HEALTH_CHECK_CONNECT_TIMEOUT_SECS),
-                                self.connect_via_upstream(&config, endpoint, Some(bind_rr.clone())),
+                                self.connect_via_upstream(
+                                    &config,
+                                    endpoint,
+                                    Some(bind_rr.clone()),
+                                    Duration::from_secs(HEALTH_CHECK_CONNECT_TIMEOUT_SECS),
+                                ),
                             )
                             .await;
 

tools/aesdiag.py

@@ -0,0 +1,403 @@
+#!/usr/bin/env python3
+"""
+AES-CBC validation tool for telemt middle proxy logs with support for noop padding.
+
+Parses log lines containing:
+  - "ME diag: derived keys and handshake plaintext" (provides write_key, write_iv, hs_plain)
+  - "ME diag: handshake ciphertext" (provides hs_cipher)
+
+For each pair it:
+  - Decrypts the ciphertext using the provided key and IV.
+  - Compares the beginning of the decrypted data with hs_plain.
+  - Attempts to identify the actual padding scheme (PKCS#7, zero padding, noop padding).
+  - Re-encrypts with different paddings and reports mismatches block by block.
+  - Accumulates statistics for final summary.
+"""
+
+import sys
+import re
+from collections import defaultdict
+from Crypto.Cipher import AES
+
+# Constants
+NOOP_FRAME = bytes([0x04, 0x00, 0x00, 0x00])   # noop frame used for padding
+
+def hex_str_to_bytes(hex_str):
+    """Convert a hex string like 'aa bb cc' to bytes."""
+    return bytes.fromhex(hex_str.replace(' ', ''))
+
+def parse_params(line):
+    """Extract key=value pairs where value is a space-separated hex string."""
+    pattern = r'(\w+)=((?:[0-9a-f]{2} )*[0-9a-f]{2})'
+    return {key: val for key, val in re.findall(pattern, line)}
+
+def pkcs7_pad(data, block_size=16):
+    """Apply PKCS#7 padding to the given data."""
+    pad_len = block_size - (len(data) % block_size)
+    if pad_len == 0:
+        pad_len = block_size
+    return data + bytes([pad_len]) * pad_len
+
+def zero_pad(data, block_size=16):
+    """Pad with zeros to the next block boundary."""
+    pad_len = block_size - (len(data) % block_size)
+    if pad_len == block_size:
+        return data  # already full blocks, no zero padding needed
+    return data + bytes(pad_len)
+
+def noop_pad(data):
+    """
+    Pad with minimal number of noop frames (b'\\x04\\x00\\x00\\x00')
+    to reach a multiple of 16 bytes.
+    """
+    block_size = 16
+    frame_len = len(NOOP_FRAME)  # 4
+    remainder = len(data) % block_size
+    if remainder == 0:
+        return data  # no padding needed
+    # We need to add k frames such that (len(data) + k*frame_len) % block_size == 0
+    # => k*frame_len ≡ -remainder (mod block_size)
+    # Since frame_len=4 and block_size=16, we need k*4 ≡ (16-remainder) mod 16
+    # k must be an integer in {1,2,3} (because 4*4=16 ≡0 mod16, so k=4 gives remainder 0, but then total increase=16,
+    # but if remainder==0 we already handled; if remainder!=0, k=4 gives (len+16)%16 == remainder, not 0,
+    # so k=4 doesn't solve unless remainder=0. Actually 4*4=16 ≡0, so k=4 gives (len+16)%16 = remainder, so still not 0.
+    # The equation is k*4 ≡ (16-remainder) mod 16. Let r=16-remainder (1..15). Then k ≡ r*inv(4) mod 4? Since mod 16,
+    # 4 has no inverse modulo 16 because gcd(4,16)=4. So solutions exist only if r is multiple of 4.
+    # Therefore remainder must be 4,8,12 (so that r = 12,8,4). This matches the idea that noop padding is only added
+    # when the plaintext length mod 16 is 4,8,12. In our logs it's always 44 mod16=12, so r=4, so k=1 works.
+    # For safety, we compute k as (block_size - remainder) // frame_len, but this only works if that value is integer.
+    need = block_size - remainder
+    if need % frame_len != 0:
+        # This shouldn't happen by protocol, but if it does, fall back to adding full blocks of noop until multiple.
+        # We'll add ceil(need/frame_len) frames.
+        k = (need + frame_len - 1) // frame_len
+    else:
+        k = need // frame_len
+    return data + NOOP_FRAME * k
+
+def unpad_pkcs7(data):
+    """Remove PKCS#7 padding (assumes correct padding)."""
+    if not data:
+        return data
+    pad_len = data[-1]
+    if pad_len < 1 or pad_len > 16:
+        return data  # not valid PKCS#7, return as is
+    # Check that all padding bytes are equal to pad_len
+    if all(b == pad_len for b in data[-pad_len:]):
+        return data[:-pad_len]
+    return data
+
+def is_noop_padded(decrypted, plain_log):
+    """
+    Check if the extra bytes after plain_log in decrypted consist of one or more NOOP_FRAMEs.
+    Returns True if they do, False otherwise.
+    """
+    extra = decrypted[len(plain_log):]
+    if len(extra) == 0:
+        return False
+    # Split into chunks of 4
+    if len(extra) % 4 != 0:
+        return False
+    for i in range(0, len(extra), 4):
+        if extra[i:i+4] != NOOP_FRAME:
+            return False
+    return True
+
+def main():
+    derived_list = []   # entries from "derived keys and handshake plaintext"
+    cipher_list = []    # entries from "handshake ciphertext"
+
+    for line in sys.stdin:
+        if 'ME diag: derived keys and handshake plaintext' in line:
+            params = parse_params(line)
+            if all(k in params for k in ('write_key', 'write_iv', 'hs_plain')):
+                derived_list.append(params)
+        elif 'ME diag: handshake ciphertext' in line:
+            params = parse_params(line)
+            if 'hs_cipher' in params:
+                cipher_list.append(params)
+
+    # Warn about count mismatch but process as many pairs as possible
+    n_pairs = min(len(derived_list), len(cipher_list))
+    if len(derived_list) != len(cipher_list):
+        print(f"\n[WARN] Number of derived entries ({len(derived_list)}) "
+              f"differs from cipher entries ({len(cipher_list)}). "
+              f"Processing first {n_pairs} pairs.\n")
+
+    # Statistics accumulators
+    stats = {
+        'total': n_pairs,
+        'key_length_ok': 0,
+        'iv_length_ok': 0,
+        'cipher_aligned': 0,
+        'decryption_match_start': 0,      # first bytes equal hs_plain
+        'pkcs7_after_unpad_matches': 0,   # after removing PKCS7, equals hs_plain
+        'extra_bytes_all_zero': 0,         # extra bytes after hs_plain are zero
+        'extra_bytes_noop': 0,             # extra bytes are noop frames
+        'pkcs7_encrypt_ok': 0,             # re-encryption with PKCS7 matches ciphertext
+        'zero_encrypt_ok': 0,               # re-encryption with zero padding matches
+        'noop_encrypt_ok': 0,                # re-encryption with noop padding matches
+        'no_padding_encrypt_ok': 0,         # only if plaintext multiple of 16 and matches
+        'no_padding_applicable': 0,         # number of tests where plaintext len %16 ==0
+    }
+
+    detailed_results = []  # store per-test summary for final heuristic
+
+    for idx, (der, ciph) in enumerate(zip(derived_list[:n_pairs], cipher_list[:n_pairs]), 1):
+        print(f"\n{'='*60}")
+        print(f"Test #{idx}")
+        print(f"{'='*60}")
+
+        # Local stats for this test
+        test_stats = defaultdict(bool)
+
+        try:
+            key = hex_str_to_bytes(der['write_key'])
+            iv = hex_str_to_bytes(der['write_iv'])
+            plain_log = hex_str_to_bytes(der['hs_plain'])
+            ciphertext = hex_str_to_bytes(ciph['hs_cipher'])
+
+            # Basic sanity checks
+            print(f"[INFO] Key length       : {len(key)} bytes (expected 32)")
+            print(f"[INFO] IV length        : {len(iv)} bytes (expected 16)")
+            print(f"[INFO] hs_plain length  : {len(plain_log)} bytes")
+            print(f"[INFO] hs_cipher length : {len(ciphertext)} bytes")
+
+            if len(key) == 32:
+                stats['key_length_ok'] += 1
+                test_stats['key_ok'] = True
+            else:
+                print("[WARN] Key length is not 32 bytes – AES-256 requires 32-byte key.")
+
+            if len(iv) == 16:
+                stats['iv_length_ok'] += 1
+                test_stats['iv_ok'] = True
+            else:
+                print("[WARN] IV length is not 16 bytes – AES-CBC requires 16-byte IV.")
+
+            if len(ciphertext) % 16 == 0:
+                stats['cipher_aligned'] += 1
+                test_stats['cipher_aligned'] = True
+            else:
+                print("[ERROR] Ciphertext length is not a multiple of 16 – invalid AES-CBC block alignment.")
+                # Skip further processing for this test
+                detailed_results.append(test_stats)
+                continue
+
+            # --- Decryption test ---
+            cipher_dec = AES.new(key, AES.MODE_CBC, iv)
+            decrypted = cipher_dec.decrypt(ciphertext)
+            print(f"[INFO] Decrypted ({len(decrypted)} bytes): {decrypted.hex()}")
+
+            # Compare beginning with hs_plain
+            match_len = min(len(plain_log), len(decrypted))
+            if decrypted[:match_len] == plain_log[:match_len]:
+                print(f"[OK] First {match_len} bytes match hs_plain.")
+                stats['decryption_match_start'] += 1
+                test_stats['decrypt_start_ok'] = True
+            else:
+                print(f"[FAIL] First bytes do NOT match hs_plain.")
+                for i in range(match_len):
+                    if decrypted[i] != plain_log[i]:
+                        print(f"       First mismatch at byte {i}: hs_plain={plain_log[i]:02x}, decrypted={decrypted[i]:02x}")
+                        break
+                test_stats['decrypt_start_ok'] = False
+
+            # --- Try to identify actual padding ---
+            # Remove possible PKCS#7 padding from decrypted data
+            decrypted_unpadded = unpad_pkcs7(decrypted)
+            if decrypted_unpadded != decrypted:
+                print(f"[INFO] After removing PKCS#7 padding: {len(decrypted_unpadded)} bytes left.")
+                if decrypted_unpadded == plain_log:
+                    print("[OK] Decrypted data with PKCS#7 removed exactly matches hs_plain.")
+                    stats['pkcs7_after_unpad_matches'] += 1
+                    test_stats['pkcs7_unpad_matches'] = True
+                else:
+                    print("[INFO] Decrypted (PKCS#7 removed) does NOT match hs_plain.")
+                    test_stats['pkcs7_unpad_matches'] = False
+            else:
+                print("[INFO] No valid PKCS#7 padding detected in decrypted data.")
+                test_stats['pkcs7_unpad_matches'] = False
+
+            # Check if the extra bytes after hs_plain in decrypted are all zero (zero padding)
+            extra = decrypted[len(plain_log):]
+            if extra and all(b == 0 for b in extra):
+                print("[INFO] Extra bytes after hs_plain are all zeros – likely zero padding.")
+                stats['extra_bytes_all_zero'] += 1
+                test_stats['extra_zero'] = True
+            else:
+                test_stats['extra_zero'] = False
+
+            # Check for noop padding in extra bytes
+            if is_noop_padded(decrypted, plain_log):
+                print(f"[OK] Extra bytes after hs_plain consist of noop frames ({NOOP_FRAME.hex()}).")
+                stats['extra_bytes_noop'] += 1
+                test_stats['extra_noop'] = True
+            else:
+                test_stats['extra_noop'] = False
+                if extra:
+                    print(f"[INFO] Extra bytes after hs_plain (hex): {extra.hex()}")
+
+            # --- Re-encryption tests ---
+            # PKCS#7
+            padded_pkcs7 = pkcs7_pad(plain_log)
+            cipher_enc = AES.new(key, AES.MODE_CBC, iv)
+            computed_pkcs7 = cipher_enc.encrypt(padded_pkcs7)
+            if computed_pkcs7 == ciphertext:
+                print("[OK] PKCS#7 padding produces the expected ciphertext.")
+                stats['pkcs7_encrypt_ok'] += 1
+                test_stats['pkcs7_enc_ok'] = True
+            else:
+                print("[FAIL] PKCS#7 padding does NOT match the ciphertext.")
+                test_stats['pkcs7_enc_ok'] = False
+                # Show block where first difference occurs
+                block_size = 16
+                for blk in range(len(ciphertext)//block_size):
+                    start = blk*block_size
+                    exp = ciphertext[start:start+block_size]
+                    comp = computed_pkcs7[start:start+block_size]
+                    if exp != comp:
+                        print(f"       First difference in block {blk}:")
+                        print(f"         expected : {exp.hex()}")
+                        print(f"         computed : {comp.hex()}")
+                        break
+
+            # Zero padding
+            padded_zero = zero_pad(plain_log)
+            # Ensure multiple of 16
+            if len(padded_zero) % 16 != 0:
+                padded_zero += bytes(16 - (len(padded_zero)%16))
+            cipher_enc_zero = AES.new(key, AES.MODE_CBC, iv)
+            computed_zero = cipher_enc_zero.encrypt(padded_zero)
+            if computed_zero == ciphertext:
+                print("[OK] Zero padding produces the expected ciphertext.")
+                stats['zero_encrypt_ok'] += 1
+                test_stats['zero_enc_ok'] = True
+            else:
+                print("[INFO] Zero padding does NOT match (expected, unless log used PKCS#7).")
+                test_stats['zero_enc_ok'] = False
+
+            # Noop padding
+            padded_noop = noop_pad(plain_log)
+            # Ensure multiple of 16 (noop_pad already returns multiple of 16)
+            cipher_enc_noop = AES.new(key, AES.MODE_CBC, iv)
+            computed_noop = cipher_enc_noop.encrypt(padded_noop)
+            if computed_noop == ciphertext:
+                print("[OK] Noop padding produces the expected ciphertext.")
+                stats['noop_encrypt_ok'] += 1
+                test_stats['noop_enc_ok'] = True
+            else:
+                print("[FAIL] Noop padding does NOT match the ciphertext.")
+                test_stats['noop_enc_ok'] = False
+                # Show block difference if needed
+                for blk in range(len(ciphertext)//16):
+                    start = blk*16
+                    if computed_noop[start:start+16] != ciphertext[start:start+16]:
+                        print(f"       First difference in block {blk}:")
+                        print(f"         expected : {ciphertext[start:start+16].hex()}")
+                        print(f"         computed : {computed_noop[start:start+16].hex()}")
+                        break
+
+            # No padding (only possible if plaintext is already multiple of 16)
+            if len(plain_log) % 16 == 0:
+                stats['no_padding_applicable'] += 1
+                cipher_enc_nopad = AES.new(key, AES.MODE_CBC, iv)
+                computed_nopad = cipher_enc_nopad.encrypt(plain_log)
+                if computed_nopad == ciphertext:
+                    print("[OK] No padding (plaintext multiple of 16) matches.")
+                    stats['no_padding_encrypt_ok'] += 1
+                    test_stats['no_pad_enc_ok'] = True
+                else:
+                    print("[INFO] No padding does NOT match.")
+                    test_stats['no_pad_enc_ok'] = False
+            else:
+                print("[INFO] Skipping no‑padding test because plaintext length is not a multiple of 16.")
+
+        except Exception as e:
+            print(f"[EXCEPTION] {e}")
+            test_stats['exception'] = True
+
+        detailed_results.append(test_stats)
+
+    # --- Final statistics and heuristic summary ---
+    print("\n" + "="*60)
+    print("STATISTICS SUMMARY")
+    print("="*60)
+    print(f"Total tests processed          : {stats['total']}")
+    print(f"Key length OK (32)              : {stats['key_length_ok']}/{stats['total']}")
+    print(f"IV length OK (16)                : {stats['iv_length_ok']}/{stats['total']}")
+    print(f"Ciphertext 16-byte aligned       : {stats['cipher_aligned']}/{stats['total']}")
+    print(f"Decryption starts with hs_plain  : {stats['decryption_match_start']}/{stats['total']}")
+    print(f"After PKCS#7 removal matches     : {stats['pkcs7_after_unpad_matches']}/{stats['total']}")
+    print(f"Extra bytes after hs_plain are 0 : {stats['extra_bytes_all_zero']}/{stats['total']}")
+    print(f"Extra bytes are noop frames       : {stats['extra_bytes_noop']}/{stats['total']}")
+    print(f"PKCS#7 re-encryption OK           : {stats['pkcs7_encrypt_ok']}/{stats['total']}")
+    print(f"Zero padding re-encryption OK     : {stats['zero_encrypt_ok']}/{stats['total']}")
+    print(f"Noop padding re-encryption OK     : {stats['noop_encrypt_ok']}/{stats['total']}")
+    if stats['no_padding_applicable'] > 0:
+        print(f"No-padding applicable tests      : {stats['no_padding_applicable']}")
+        print(f"No-padding re-encryption OK       : {stats['no_padding_encrypt_ok']}/{stats['no_padding_applicable']}")
+
+    # Heuristic: determine most likely padding
+    print("\n" + "="*60)
+    print("HEURISTIC CONCLUSION")
+    print("="*60)
+
+    if stats['decryption_match_start'] == stats['total']:
+        print("✓ All tests: first bytes of decrypted data match hs_plain → keys and IV are correct.")
+    else:
+        print("✗ Some tests: first bytes mismatch → possible key/IV issues or corrupted ciphertext.")
+
+    # Guess padding based on re-encryption success and extra bytes
+    candidates = []
+    if stats['pkcs7_encrypt_ok'] == stats['total']:
+        candidates.append("PKCS#7")
+    if stats['zero_encrypt_ok'] == stats['total']:
+        candidates.append("zero padding")
+    if stats['noop_encrypt_ok'] == stats['total']:
+        candidates.append("noop padding")
+    if stats['no_padding_applicable'] == stats['total'] and stats['no_padding_encrypt_ok'] == stats['total']:
+        candidates.append("no padding")
+
+    if len(candidates) == 1:
+        print(f"✓ All tests consistent with padding scheme: {candidates[0]}.")
+    elif len(candidates) > 1:
+        print(f"⚠ Multiple padding schemes succeed in all tests: {', '.join(candidates)}. This is unusual.")
+    else:
+        # No scheme succeeded in all tests – look at ratios
+        print("Mixed padding results:")
+        total = stats['total']
+        pkcs7_ratio = stats['pkcs7_encrypt_ok'] / total if total else 0
+        zero_ratio = stats['zero_encrypt_ok'] / total if total else 0
+        noop_ratio = stats['noop_encrypt_ok'] / total if total else 0
+        print(f"  PKCS#7 success = {stats['pkcs7_encrypt_ok']}/{total} ({pkcs7_ratio*100:.1f}%)")
+        print(f"  Zero success   = {stats['zero_encrypt_ok']}/{total} ({zero_ratio*100:.1f}%)")
+        print(f"  Noop success   = {stats['noop_encrypt_ok']}/{total} ({noop_ratio*100:.1f}%)")
+
+        if noop_ratio > max(pkcs7_ratio, zero_ratio):
+            print("→ Noop padding is most frequent. Check if extra bytes are indeed noop frames.")
+        elif pkcs7_ratio > zero_ratio:
+            print("→ PKCS#7 is most frequent, but fails in some tests.")
+        elif zero_ratio > pkcs7_ratio:
+            print("→ Zero padding is most frequent, but fails in some tests.")
+        else:
+            print("→ No clear winner; possibly a different padding scheme or random data.")
+
+    # Additional heuristics based on extra bytes
+    if stats['extra_bytes_noop'] == stats['total']:
+        print("✓ All tests: extra bytes after hs_plain are noop frames → strongly indicates noop padding.")
+    if stats['extra_bytes_all_zero'] == stats['total']:
+        print("✓ All tests: extra bytes are zeros → suggests zero padding.")
+
+    # Final health check
+    if (stats['decryption_match_start'] == stats['total'] and
+        (stats['pkcs7_encrypt_ok'] == stats['total'] or
+         stats['zero_encrypt_ok'] == stats['total'] or
+         stats['noop_encrypt_ok'] == stats['total'] or
+         stats['no_padding_encrypt_ok'] == stats['no_padding_applicable'] == stats['total'])):
+        print("\n✅ OVERALL: All tests consistent. The encryption parameters and padding are correct.")
+    else:
+        print("\n⚠️ OVERALL: Inconsistencies detected. Review the detailed output for failing tests.")
+
+if __name__ == '__main__':
+    main()

tools/zbx_telemt_template.yaml

@@ -47,6 +47,54 @@ zabbix_export:
           tags:
             - tag: Application
               value: 'Server connections'
+        - uuid: 2af8ff0f27e4408db3f9798dc3141457
+          name: 'Full forensic desync logs emitted'
+          type: DEPENDENT
+          key: telemt.desync_full_logged_total
+          delay: '0'
+          preprocessing:
+            - type: PROMETHEUS_PATTERN
+              parameters:
+                - telemt_desync_full_logged_total
+                - value
+                - ''
+          master_item:
+            key: telemt.prom_metrics
+          tags:
+            - tag: Application
+              value: 'Telemt other'
+        - uuid: f4439948a49f4b1d85c3eeee963259bc
+          name: 'Suppressed desync forensic events'
+          type: DEPENDENT
+          key: telemt.desync_suppressed_total
+          delay: '0'
+          preprocessing:
+            - type: PROMETHEUS_PATTERN
+              parameters:
+                - telemt_desync_suppressed_total
+                - value
+                - ''
+          master_item:
+            key: telemt.prom_metrics
+          tags:
+            - tag: Application
+              value: 'Telemt other'
+        - uuid: 721627b8c10a414a82be1e08873604c1
+          name: 'Total crypto-desync detections'
+          type: DEPENDENT
+          key: telemt.desync_total
+          delay: '0'
+          preprocessing:
+            - type: PROMETHEUS_PATTERN
+              parameters:
+                - telemt_desync_total
+                - value
+                - ''
+          master_item:
+            key: telemt.prom_metrics
+          tags:
+            - tag: Application
+              value: 'Telemt other'
         - uuid: 1618272cf68e44509425f5fab029db7b
           name: 'Handshake timeouts total'
           type: DEPENDENT
@@ -64,6 +112,152 @@ zabbix_export:
           tags:
             - tag: Application
               value: 'Server connections'
+        - uuid: 4e5c0d10a4494c959445b4cd7a2e696e
+          name: 'ME CRC mismatches'
+          type: DEPENDENT
+          key: telemt.me_crc_mismatch_total
+          delay: '0'
+          preprocessing:
+            - type: PROMETHEUS_PATTERN
+              parameters:
+                - telemt_me_crc_mismatch_total
+                - value
+                - ''
+          master_item:
+            key: telemt.prom_metrics
+          tags:
+            - tag: Application
+              value: 'Middle-End connections'
+        - uuid: 21a4a48b6e98457d87c56c3ae7b56c55
+          name: 'ME endpoint quarantines due to rapid flaps'
+          type: DEPENDENT
+          key: telemt.me_endpoint_quarantine_total
+          delay: '0'
+          preprocessing:
+            - type: PROMETHEUS_PATTERN
+              parameters:
+                - telemt_me_endpoint_quarantine_total
+                - value
+                - ''
+          master_item:
+            key: telemt.prom_metrics
+          tags:
+            - tag: Application
+              value: 'Telemt other'
+        - uuid: c8ffc30dc3d94a6d9085ac79413fbdd6
+          name: 'Runtime ME writer floor policy mode'
+          type: DEPENDENT
+          key: telemt.me_floor_mode
+          delay: '0'
+          value_type: TEXT
+          trends: '0'
+          preprocessing:
+            - type: PROMETHEUS_PATTERN
+              parameters:
+                - 'telemt_me_floor_mode == 1'
+                - label
+                - mode
+          master_item:
+            key: telemt.prom_metrics
+          tags:
+            - tag: Application
+              value: 'Telemt other'
+        - uuid: 4814b52d5d184f63b64654e7635bdf6a
+          name: 'ME handshake rejects from upstream'
+          type: DEPENDENT
+          key: telemt.me_handshake_reject_total
+          delay: '0'
+          preprocessing:
+            - type: PROMETHEUS_PATTERN
+              parameters:
+                - telemt_me_handshake_reject_total
+                - value
+                - ''
+          master_item:
+            key: telemt.prom_metrics
+          tags:
+            - tag: Application
+              value: 'Telemt other'
+        - uuid: 72d11caecefb4472b6c3e07f1ee90053
+          name: 'Hardswap cycles that reused an existing pending generation'
+          type: DEPENDENT
+          key: telemt.me_hardswap_pending_reuse_total
+          delay: '0'
+          preprocessing:
+            - type: PROMETHEUS_PATTERN
+              parameters:
+                - telemt_me_hardswap_pending_reuse_total
+                - value
+                - ''
+          master_item:
+            key: telemt.prom_metrics
+          tags:
+            - tag: Application
+              value: 'Telemt other'
+        - uuid: 447030854e8840a393874f54e25861d5
+          name: 'Pending hardswap generations reset by TTL expiration'
+          type: DEPENDENT
+          key: telemt.me_hardswap_pending_ttl_expired_total
+          delay: '0'
+          preprocessing:
+            - type: PROMETHEUS_PATTERN
+              parameters:
+                - telemt_me_hardswap_pending_ttl_expired_total
+                - value
+                - ''
+          master_item:
+            key: telemt.prom_metrics
+          tags:
+            - tag: Application
+              value: 'Telemt other'
+        - uuid: 47f55dd7d9394405b1c0eba6e6eb3e5c
+          name: 'ME idle writers closed by peer'
+          type: DEPENDENT
+          key: telemt.me_idle_close_by_peer_total
+          delay: '0'
+          preprocessing:
+            - type: PROMETHEUS_PATTERN
+              parameters:
+                - telemt_me_idle_close_by_peer_total
+                - value
+                - ''
+          master_item:
+            key: telemt.prom_metrics
+          tags:
+            - tag: Application
+              value: 'Telemt other'
+        - uuid: 9e4598efbfe246fab9360270002b0cfa
+          name: 'ME KDF input drift detections'
+          type: DEPENDENT
+          key: telemt.me_kdf_drift_total
+          delay: '0'
+          preprocessing:
+            - type: PROMETHEUS_PATTERN
+              parameters:
+                - telemt_me_kdf_drift_total
+                - value
+                - ''
+          master_item:
+            key: telemt.prom_metrics
+          tags:
+            - tag: Application
+              value: 'Telemt other'
+        - uuid: 565cc9780c5541bfb7acbb1f4973b5fc
+          name: 'ME KDF client-port changes with stable non-port material'
+          type: DEPENDENT
+          key: telemt.me_kdf_port_only_drift_total
+          delay: '0'
+          preprocessing:
+            - type: PROMETHEUS_PATTERN
+              parameters:
+                - telemt_me_kdf_port_only_drift_total
+                - value
+                - ''
+          master_item:
+            key: telemt.prom_metrics
+          tags:
+            - tag: Application
+              value: 'Telemt other'
         - uuid: fb95391c7f894e3eb6984b92885813d2
           name: 'ME keepalive send failures'
           type: DEPENDENT
@@ -81,6 +275,22 @@ zabbix_export:
           tags:
             - tag: Application
               value: 'Middle-End connections'
+        - uuid: 7b5995401195430e9f9e02e5dd8c3313
+          name: 'ME keepalive pong replies'
+          type: DEPENDENT
+          key: telemt.me_keepalive_pong_total
+          delay: '0'
+          preprocessing:
+            - type: PROMETHEUS_PATTERN
+              parameters:
+                - telemt_me_keepalive_pong_total
+                - value
+                - ''
+          master_item:
+            key: telemt.prom_metrics
+          tags:
+            - tag: Application
+              value: 'Middle-End connections'
         - uuid: fb95391c7f894e3eb6984b92885813c2
           name: 'ME keepalive frames sent'
           type: DEPENDENT
@@ -98,6 +308,38 @@ zabbix_export:
           tags:
             - tag: Application
               value: 'Middle-End connections'
+        - uuid: da5af5fd691d4f40bc6cad78b4758eac
+          name: 'ME keepalive ping timeouts'
+          type: DEPENDENT
+          key: telemt.me_keepalive_timeout_total
+          delay: '0'
+          preprocessing:
+            - type: PROMETHEUS_PATTERN
+              parameters:
+                - telemt_me_keepalive_timeout_total
+                - value
+                - ''
+          master_item:
+            key: telemt.prom_metrics
+          tags:
+            - tag: Application
+              value: 'Middle-End connections'
+        - uuid: 50b45e494d584a7b86fca8b80c727411
+          name: 'ME reader EOF terminations'
+          type: DEPENDENT
+          key: telemt.me_reader_eof_total
+          delay: '0'
+          preprocessing:
+            - type: PROMETHEUS_PATTERN
+              parameters:
+                - telemt_me_reader_eof_total
+                - value
+                - ''
+          master_item:
+            key: telemt.prom_metrics
+          tags:
+            - tag: Application
+              value: 'Telemt other'
         - uuid: fb95391c7f894e3eb6984b92885811a2
           name: 'ME reconnect attempts'
           type: DEPENDENT
@@ -132,6 +374,470 @@ zabbix_export:
           tags:
             - tag: Application
               value: 'Middle-End connections'
+        - uuid: 6288b537b7964aadb8a483abd716855a
+          name: 'Immediate ME refill failures'
+          type: DEPENDENT
+          key: telemt.me_refill_failed_total
+          delay: '0'
+          preprocessing:
+            - type: PROMETHEUS_PATTERN
+              parameters:
+                - telemt_me_refill_failed_total
+                - value
+                - ''
+          master_item:
+            key: telemt.prom_metrics
+          tags:
+            - tag: Application
+              value: 'Telemt other'
+        - uuid: 8450bdb48f9b4505beb8fdfc665b37c5
+          name: 'Immediate ME refill skips due to inflight dedup'
+          type: DEPENDENT
+          key: telemt.me_refill_skipped_inflight_total
+          delay: '0'
+          preprocessing:
+            - type: PROMETHEUS_PATTERN
+              parameters:
+                - telemt_me_refill_skipped_inflight_total
+                - value
+                - ''
+          master_item:
+            key: telemt.prom_metrics
+          tags:
+            - tag: Application
+              value: 'Telemt other'
+        - uuid: cb192264c03a40578140863970333515
+          name: 'Immediate ME refill runs started'
+          type: DEPENDENT
+          key: telemt.me_refill_triggered_total
+          delay: '0'
+          preprocessing:
+            - type: PROMETHEUS_PATTERN
+              parameters:
+                - telemt_me_refill_triggered_total
+                - value
+                - ''
+          master_item:
+            key: telemt.prom_metrics
+          tags:
+            - tag: Application
+              value: 'Telemt other'
+        - uuid: 8f46b374332848fba0daba72e17eaad0
+          name: 'ME route drops: channel closed'
+          type: DEPENDENT
+          key: telemt.me_route_drop_channel_closed_total
+          delay: '0'
+          preprocessing:
+            - type: PROMETHEUS_PATTERN
+              parameters:
+                - telemt_me_route_drop_channel_closed_total
+                - value
+                - ''
+          master_item:
+            key: telemt.prom_metrics
+          tags:
+            - tag: Application
+              value: 'Middle-End connections'
+        - uuid: de5fa7a316554d099bcf5e000b33bfed
+          name: 'ME route drops: no conn'
+          type: DEPENDENT
+          key: telemt.me_route_drop_no_conn_total
+          delay: '0'
+          preprocessing:
+            - type: PROMETHEUS_PATTERN
+              parameters:
+                - telemt_me_route_drop_no_conn_total
+                - value
+                - ''
+          master_item:
+            key: telemt.prom_metrics
+          tags:
+            - tag: Application
+              value: 'Middle-End connections'
+        - uuid: d9e1630ce38946f7a8d179187793f12c
+          name: 'ME route drops: queue full by adaptive profile'
+          type: DEPENDENT
+          key: telemt.me_route_drop_queue_full_profile_total
+          delay: '0'
+          preprocessing:
+            - type: PROMETHEUS_PATTERN
+              parameters:
+                - 'telemt_me_route_drop_queue_full_profile_total == 1'
+                - label
+                - profile
+          master_item:
+            key: telemt.prom_metrics
+          tags:
+            - tag: Application
+              value: 'Telemt other'
+        - uuid: d5caefb8978e4f3eac4dcdecd4655c46
+          name: 'ME route drops: queue full'
+          type: DEPENDENT
+          key: telemt.me_route_drop_queue_full_total
+          delay: '0'
+          preprocessing:
+            - type: PROMETHEUS_PATTERN
+              parameters:
+                - telemt_me_route_drop_queue_full_total
+                - value
+                - ''
+          master_item:
+            key: telemt.prom_metrics
+          tags:
+            - tag: Application
+              value: 'Telemt other'
+        - uuid: f682298c2dfc46dda45771a58faa9ffa
+          name: 'Service RPC_CLOSE_EXT sent after activity signals'
+          type: DEPENDENT
+          key: telemt.me_rpc_proxy_req_signal_close_sent_total
+          delay: '0'
+          preprocessing:
+            - type: PROMETHEUS_PATTERN
+              parameters:
+                - telemt_me_rpc_proxy_req_signal_close_sent_total
+                - value
+                - ''
+          master_item:
+            key: telemt.prom_metrics
+          tags:
+            - tag: Application
+              value: 'Telemt other'
+        - uuid: 5db4bdc93959473eade9281c221e34b6
+          name: 'Service RPC_PROXY_REQ activity signal failures'
+          type: DEPENDENT
+          key: telemt.me_rpc_proxy_req_signal_failed_total
+          delay: '0'
+          preprocessing:
+            - type: PROMETHEUS_PATTERN
+              parameters:
+                - telemt_me_rpc_proxy_req_signal_failed_total
+                - value
+                - ''
+          master_item:
+            key: telemt.prom_metrics
+          tags:
+            - tag: Application
+              value: 'Telemt other'
+        - uuid: 4e75611bc3854415b63a1863e9bf176f
+          name: 'Service RPC_PROXY_REQ responses observed'
+          type: DEPENDENT
+          key: telemt.me_rpc_proxy_req_signal_response_total
+          delay: '0'
+          preprocessing:
+            - type: PROMETHEUS_PATTERN
+              parameters:
+                - telemt_me_rpc_proxy_req_signal_response_total
+                - value
+                - ''
+          master_item:
+            key: telemt.prom_metrics
+          tags:
+            - tag: Application
+              value: 'Telemt other'
+        - uuid: ecbffb29f2784839bea0ce2a38393438
+          name: 'Service RPC_PROXY_REQ activity signals sent'
+          type: DEPENDENT
+          key: telemt.me_rpc_proxy_req_signal_sent_total
+          delay: '0'
+          preprocessing:
+            - type: PROMETHEUS_PATTERN
+              parameters:
+                - telemt_me_rpc_proxy_req_signal_sent_total
+                - value
+                - ''
+          master_item:
+            key: telemt.prom_metrics
+          tags:
+            - tag: Application
+              value: 'Telemt other'
+        - uuid: 078eff3deeec435597f0c531457bb906
+          name: 'Service RPC_PROXY_REQ skipped due to missing writer metadata'
+          type: DEPENDENT
+          key: telemt.me_rpc_proxy_req_signal_skipped_no_meta_total
+          delay: '0'
+          preprocessing:
+            - type: PROMETHEUS_PATTERN
+              parameters:
+                - telemt_me_rpc_proxy_req_signal_skipped_no_meta_total
+                - value
+                - ''
+          master_item:
+            key: telemt.prom_metrics
+          tags:
+            - tag: Application
+              value: 'Telemt other'
+        - uuid: 7429ffbd94a340d7a600bc1690eb57e7
+          name: 'ME sequence mismatches'
+          type: DEPENDENT
+          key: telemt.me_seq_mismatch_total
+          delay: '0'
+          preprocessing:
+            - type: PROMETHEUS_PATTERN
+              parameters:
+                - telemt_me_seq_mismatch_total
+                - value
+                - ''
+          master_item:
+            key: telemt.prom_metrics
+          tags:
+            - tag: Application
+              value: 'Telemt other'
+        - uuid: 0f1f77ae34df4a48b36ad263359b5ad3
+          name: 'Single-endpoint DC outage transitions to active state'
+          type: DEPENDENT
+          key: telemt.me_single_endpoint_outage_enter_total
+          delay: '0'
+          preprocessing:
+            - type: PROMETHEUS_PATTERN
+              parameters:
+                - telemt_me_single_endpoint_outage_enter_total
+                - value
+                - ''
+          master_item:
+            key: telemt.prom_metrics
+          tags:
+            - tag: Application
+              value: 'Telemt other'
+        - uuid: 63d44ef672ff4df288914eb98f6fa72c
+          name: 'Single-endpoint DC outage recovery transitions'
+          type: DEPENDENT
+          key: telemt.me_single_endpoint_outage_exit_total
+          delay: '0'
+          preprocessing:
+            - type: PROMETHEUS_PATTERN
+              parameters:
+                - telemt_me_single_endpoint_outage_exit_total
+                - value
+                - ''
+          master_item:
+            key: telemt.prom_metrics
+          tags:
+            - tag: Application
+              value: 'Telemt other'
+        - uuid: 1b72ff95f1ba4fb2924aa3a129b22f4d
+          name: 'Reconnect attempts performed during single-endpoint outages'
+          type: DEPENDENT
+          key: telemt.me_single_endpoint_outage_reconnect_attempt_total
+          delay: '0'
+          preprocessing:
+            - type: PROMETHEUS_PATTERN
+              parameters:
+                - telemt_me_single_endpoint_outage_reconnect_attempt_total
+                - value
+                - ''
+          master_item:
+            key: telemt.prom_metrics
+          tags:
+            - tag: Application
+              value: 'Telemt other'
+        - uuid: 466bb352d55946a0bb78efc63e1ed71e
+          name: 'Successful reconnect attempts during single-endpoint outages'
+          type: DEPENDENT
+          key: telemt.me_single_endpoint_outage_reconnect_success_total
+          delay: '0'
+          preprocessing:
+            - type: PROMETHEUS_PATTERN
+              parameters:
+                - telemt_me_single_endpoint_outage_reconnect_success_total
+                - value
+                - ''
+          master_item:
+            key: telemt.prom_metrics
+          tags:
+            - tag: Application
+              value: 'Telemt other'
+        - uuid: 295b4a519a4d46f7b1ddbdf5b5268751
+          name: 'Outage reconnect attempts that bypassed quarantine'
+          type: DEPENDENT
+          key: telemt.me_single_endpoint_quarantine_bypass_total
+          delay: '0'
+          preprocessing:
+            - type: PROMETHEUS_PATTERN
+              parameters:
+                - telemt_me_single_endpoint_quarantine_bypass_total
+                - value
+                - ''
+          master_item:
+            key: telemt.prom_metrics
+          tags:
+            - tag: Application
+              value: 'Telemt other'
+        - uuid: bffa4861f83f4445bb0b2259e100e04c
+          name: 'Shadow rotations skipped because endpoint is quarantined'
+          type: DEPENDENT
+          key: telemt.me_single_endpoint_shadow_rotate_skipped_quarantine_total
+          delay: '0'
+          preprocessing:
+            - type: PROMETHEUS_PATTERN
+              parameters:
+                - telemt_me_single_endpoint_shadow_rotate_skipped_quarantine_total
+                - value
+                - ''
+          master_item:
+            key: telemt.prom_metrics
+          tags:
+            - tag: Application
+              value: 'Telemt other'
+        - uuid: f80ce02b50824f8ea0ddabac9ff97757
+          name: 'Successful periodic shadow rotations for single-endpoint DC groups'
+          type: DEPENDENT
+          key: telemt.me_single_endpoint_shadow_rotate_total
+          delay: '0'
+          preprocessing:
+            - type: PROMETHEUS_PATTERN
+              parameters:
+                - telemt_me_single_endpoint_shadow_rotate_total
+                - value
+                - ''
+          master_item:
+            key: telemt.prom_metrics
+          tags:
+            - tag: Application
+              value: 'Telemt other'
+        - uuid: bf2a0ff89c314f78904aa43351601111
+          name: 'Total ME writer removals'
+          type: DEPENDENT
+          key: telemt.me_writer_removed_total
+          delay: '0'
+          preprocessing:
+            - type: PROMETHEUS_PATTERN
+              parameters:
+                - telemt_me_writer_removed_total
+                - value
+                - ''
+          master_item:
+            key: telemt.prom_metrics
+          tags:
+            - tag: Application
+              value: 'Telemt other'
+        - uuid: 0d12ea02187745eba55498dfb16daa5c
+          name: 'Unexpected writer removals not yet compensated by restore'
+          type: DEPENDENT
+          key: telemt.me_writer_removed_unexpected_minus_restored_total
+          delay: '0'
+          preprocessing:
+            - type: PROMETHEUS_PATTERN
+              parameters:
+                - telemt_me_writer_removed_unexpected_minus_restored_total
+                - value
+                - ''
+          master_item:
+            key: telemt.prom_metrics
+          tags:
+            - tag: Application
+              value: 'Telemt other'
+        - uuid: 644278e7f87947e1a49483ba4487e32b
+          name: 'Unexpected ME writer removals that triggered refill'
+          type: DEPENDENT
+          key: telemt.me_writer_removed_unexpected_total
+          delay: '0'
+          preprocessing:
+            - type: PROMETHEUS_PATTERN
+              parameters:
+                - telemt_me_writer_removed_unexpected_total
+                - value
+                - ''
+          master_item:
+            key: telemt.prom_metrics
+          tags:
+            - tag: Application
+              value: 'Telemt other'
+        - uuid: a6c24dfc85d643dab1c81fc1e63fe3cc
+          name: 'Refilled ME writer restored via fallback endpoint'
+          type: DEPENDENT
+          key: telemt.me_writer_restored_fallback_total
+          delay: '0'
+          preprocessing:
+            - type: PROMETHEUS_PATTERN
+              parameters:
+                - telemt_me_writer_restored_fallback_total
+                - value
+                - ''
+          master_item:
+            key: telemt.prom_metrics
+          tags:
+            - tag: Application
+              value: 'Telemt other'
+        - uuid: d7d0a78ca6da4bb9b4a0991fd83149cf
+          name: 'Refilled ME writer restored on the same endpoint'
+          type: DEPENDENT
+          key: telemt.me_writer_restored_same_endpoint_total
+          delay: '0'
+          preprocessing:
+            - type: PROMETHEUS_PATTERN
+              parameters:
+                - telemt_me_writer_restored_same_endpoint_total
+                - value
+                - ''
+          master_item:
+            key: telemt.prom_metrics
+          tags:
+            - tag: Application
+              value: 'Telemt other'
+        - uuid: beb906ab89564cf9adfbb7b1d4553c44
+          name: 'Active draining ME writers'
+          type: DEPENDENT
+          key: telemt.pool_drain_active
+          delay: '0'
+          preprocessing:
+            - type: PROMETHEUS_PATTERN
+              parameters:
+                - telemt_pool_drain_active
+                - value
+                - ''
+          master_item:
+            key: telemt.prom_metrics
+          tags:
+            - tag: Application
+              value: 'Telemt other'
+        - uuid: 2f0926e00d7a4e5aa1783cb33b1192ea
+          name: 'Forced close events for draining writers'
+          type: DEPENDENT
+          key: telemt.pool_force_close_total
+          delay: '0'
+          preprocessing:
+            - type: PROMETHEUS_PATTERN
+              parameters:
+                - telemt_pool_force_close_total
+                - value
+                - ''
+          master_item:
+            key: telemt.prom_metrics
+          tags:
+            - tag: Application
+              value: 'Telemt other'
+        - uuid: 70d0b4da6079435ebe978e99bda8f1d3
+          name: 'Stale writer fallback picks for new binds'
+          type: DEPENDENT
+          key: telemt.pool_stale_pick_total
+          delay: '0'
+          preprocessing:
+            - type: PROMETHEUS_PATTERN
+              parameters:
+                - telemt_pool_stale_pick_total
+                - value
+                - ''
+          master_item:
+            key: telemt.prom_metrics
+          tags:
+            - tag: Application
+              value: 'Telemt other'
+        - uuid: 8a1d240b9b554905a8add9bf730bf1f4
+          name: 'Successful ME pool swaps'
+          type: DEPENDENT
+          key: telemt.pool_swap_total
+          delay: '0'
+          preprocessing:
+            - type: PROMETHEUS_PATTERN
+              parameters:
+                - telemt_pool_swap_total
+                - value
+                - ''
+          master_item:
+            key: telemt.prom_metrics
+          tags:
+            - tag: Application
+              value: 'Telemt other'
         - uuid: 991b1858e3f94b3098ff0f84859efc41
           name: 'Prometheus metrics'
           type: HTTP_AGENT
@@ -139,11 +845,158 @@ zabbix_export:
           value_type: TEXT
           trends: '0'
           url: '{$TELEMT_URL}'
+        - uuid: cef2547bb9464d10b11b6c19beac089d
+          name: 'Invalid secure frame lengths'
+          type: DEPENDENT
+          key: telemt.secure_padding_invalid_total
+          delay: '0'
+          preprocessing:
+            - type: PROMETHEUS_PATTERN
+              parameters:
+                - telemt_secure_padding_invalid_total
+                - value
+                - ''
+          master_item:
+            key: telemt.prom_metrics
+          tags:
+            - tag: Application
+              value: 'Telemt other'
+        - uuid: c164d7b59bdc4429a23b908558de8cf4
+          name: 'Runtime core telemetry switch'
+          type: DEPENDENT
+          key: telemt.telemetry_core_enabled
+          delay: '0'
+          preprocessing:
+            - type: PROMETHEUS_PATTERN
+              parameters:
+                - telemt_telemetry_core_enabled
+                - value
+                - ''
+          master_item:
+            key: telemt.prom_metrics
+          tags:
+            - tag: Application
+              value: 'Telemt other'
+        - uuid: ff16438417d842178d26033d13520833
+          name: 'Runtime ME telemetry level flag'
+          type: DEPENDENT
+          key: telemt.telemetry_me_level
+          delay: '0'
+          value_type: TEXT
+          trends: '0'
+          preprocessing:
+            - type: PROMETHEUS_PATTERN
+              parameters:
+                - 'telemt_telemetry_me_level == 1'
+                - label
+                - level
+          master_item:
+            key: telemt.prom_metrics
+          tags:
+            - tag: Application
+              value: 'Telemt other'
+        - uuid: 9fec0bb7c3c84ada96668b74d5849556
+          name: 'Runtime per-user telemetry switch'
+          type: DEPENDENT
+          key: telemt.telemetry_user_enabled
+          delay: '0'
+          preprocessing:
+            - type: PROMETHEUS_PATTERN
+              parameters:
+                - telemt_telemetry_user_enabled
+                - value
+                - ''
+          master_item:
+            key: telemt.prom_metrics
+          tags:
+            - tag: Application
+              value: 'Telemt other'
+        - uuid: 378b765aa7bc4a4ea87d3bc876c50d12
+          name: 'User-labeled metric series suppression flag'
+          type: DEPENDENT
+          key: telemt.telemetry_user_series_suppressed
+          delay: '0'
+          preprocessing:
+            - type: PROMETHEUS_PATTERN
+              parameters:
+                - telemt_telemetry_user_series_suppressed
+                - value
+                - ''
+          master_item:
+            key: telemt.prom_metrics
+          tags:
+            - tag: Application
+              value: 'Telemt other'
+        - uuid: 17972d992fa84fc1b53fdefed123ccd8
+          name: 'Upstream connect attempts across all requests'
+          type: DEPENDENT
+          key: telemt.upstream_connect_attempt_total
+          delay: '0'
+          preprocessing:
+            - type: PROMETHEUS_PATTERN
+              parameters:
+                - telemt_upstream_connect_attempt_total
+                - value
+                - ''
+          master_item:
+            key: telemt.prom_metrics
+          tags:
+            - tag: Application
+              value: 'Telemt other'
+        - uuid: 38627dd1cb7145e180d111bdee1d2c23
+          name: 'Hard errors that triggered upstream connect failfast'
+          type: DEPENDENT
+          key: telemt.upstream_connect_failfast_hard_error_total
+          delay: '0'
+          preprocessing:
+            - type: PROMETHEUS_PATTERN
+              parameters:
+                - telemt_upstream_connect_failfast_hard_error_total
+                - value
+                - ''
+          master_item:
+            key: telemt.prom_metrics
+          tags:
+            - tag: Application
+              value: 'Telemt other'
+        - uuid: 0ffd4c35b6734c83bd77c59f30bf3246
+          name: 'Failed upstream connect request cycles'
+          type: DEPENDENT
+          key: telemt.upstream_connect_fail_total
+          delay: '0'
+          preprocessing:
+            - type: PROMETHEUS_PATTERN
+              parameters:
+                - telemt_upstream_connect_fail_total
+                - value
+                - ''
+          master_item:
+            key: telemt.prom_metrics
+          tags:
+            - tag: Application
+              value: 'Telemt other'
+        - uuid: 7da255f4f38c4095921bc876d16d3586
+          name: 'Successful upstream connect request cycles'
+          type: DEPENDENT
+          key: telemt.upstream_connect_success_total
+          delay: '0'
+          preprocessing:
+            - type: PROMETHEUS_PATTERN
+              parameters:
+                - telemt_upstream_connect_success_total
+                - value
+                - ''
+          master_item:
+            key: telemt.prom_metrics
+          tags:
+            - tag: Application
+              value: 'Telemt other'
         - uuid: fb95391c7f894e3eb6984b92885813b2
           name: 'Telemt Uptime'
           type: DEPENDENT
           key: telemt.uptime
           delay: '0'
+          value_type: FLOAT
           trends: '0'
           units: s
           preprocessing:
@@ -180,6 +1033,56 @@ zabbix_export:
               tags:
                 - tag: Application
                   value: 'Users connections'
+            - uuid: f7ad02d1635542b584bba5941375ae41
+              name: 'Current number of unique active IPs by {#TELEMT_USER}'
+              type: DEPENDENT
+              key: 'telemt.ips_current_[{#TELEMT_USER}]'
+              delay: '0'
+              preprocessing:
+                - type: PROMETHEUS_PATTERN
+                  parameters:
+                    - 'telemt_user_unique_ips_current{user="{#TELEMT_USER}"}'
+                    - value
+                    - ''
+              master_item:
+                key: telemt.prom_metrics
+              tags:
+                - tag: Application
+                  value: 'Users IPs'
+            - uuid: 100b09bf1cff420495c5c105bdb0af6c
+              name: 'Configured unique IP limit to {#TELEMT_USER}'
+              type: DEPENDENT
+              key: 'telemt.ips_limit_[{#TELEMT_USER}]'
+              delay: '0'
+              description: '0 means unlimited'
+              preprocessing:
+                - type: PROMETHEUS_PATTERN
+                  parameters:
+                    - 'telemt_user_unique_ips_limit{user="{#TELEMT_USER}"}'
+                    - value
+                    - ''
+              master_item:
+                key: telemt.prom_metrics
+              tags:
+                - tag: Application
+                  value: 'Users IPs'
+            - uuid: ef3ac8f5c5d746bbaa4b0b698ba0d9f6
+              name: 'Unique IP usage ratio by {#TELEMT_USER}'
+              type: DEPENDENT
+              key: 'telemt.ips_utilization_[{#TELEMT_USER}]'
+              delay: '0'
+              value_type: FLOAT
+              preprocessing:
+                - type: PROMETHEUS_PATTERN
+                  parameters:
+                    - 'telemt_user_unique_ips_utilization{user="{#TELEMT_USER}"}'
+                    - value
+                    - ''
+              master_item:
+                key: telemt.prom_metrics
+              tags:
+                - tag: Application
+                  value: 'Users IPs'
             - uuid: 3ccce91ab5d54b4d972280c7b7bda910
               name: 'Messages received from {#TELEMT_USER}'
               type: DEPENDENT