Merge pull request #509 from telemt/bump

Update Cargo.toml

Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "telemt"
-version = "3.3.26"
+version = "3.3.28"
 edition = "2024"
 
 [dependencies]

README.md

@@ -21,9 +21,7 @@
 
 #### О релизах
 
-[3.3.15](https://github.com/telemt/telemt/releases/tag/3.3.15) по итогам работы в продакшн признан одним из самых стабильных и рекомендуется к использованию, когда cutting-edge фичи некритичны!
-
-[3.3.24](https://github.com/telemt/telemt/releases/tag/3.3.24) даёт баланс стабильности и передового функционала, а так же последние исправления по безопасности и багам
+[3.3.27](https://github.com/telemt/telemt/releases/tag/3.3.27) даёт баланс стабильности и передового функционала, а так же последние исправления по безопасности и багам
 
 Будем рады вашему фидбеку и предложениям по улучшению — особенно в части **API**, **статистики**, **UX**
 
@@ -44,9 +42,7 @@
 
 #### About releases
 
-[3.3.15](https://github.com/telemt/telemt/releases/tag/3.3.15) is, based on the results of his work in production, recognized as one of the most stable and recommended for use when cutting-edge features are not so necessary!
-
-[3.3.24](https://github.com/telemt/telemt/releases/tag/3.3.24) provides a balance of stability and advanced functionality, as well as the latest security and bug fixes
+[3.3.27](https://github.com/telemt/telemt/releases/tag/3.3.27) provides a balance of stability and advanced functionality, as well as the latest security and bug fixes
 
 We are looking forward to your feedback and improvement proposals — especially regarding **API**, **statistics**, **UX**
 

src/api/model.rs

@@ -205,6 +205,16 @@ pub(super) struct ZeroPoolData {
     pub(super) refill_failed_total: u64,
     pub(super) writer_restored_same_endpoint_total: u64,
     pub(super) writer_restored_fallback_total: u64,
+    pub(super) teardown_attempt_total_normal: u64,
+    pub(super) teardown_attempt_total_hard_detach: u64,
+    pub(super) teardown_success_total_normal: u64,
+    pub(super) teardown_success_total_hard_detach: u64,
+    pub(super) teardown_timeout_total: u64,
+    pub(super) teardown_escalation_total: u64,
+    pub(super) teardown_noop_total: u64,
+    pub(super) teardown_cleanup_side_effect_failures_total: u64,
+    pub(super) teardown_duration_count_total: u64,
+    pub(super) teardown_duration_sum_seconds_total: f64,
 }
 
 #[derive(Serialize, Clone)]

src/api/runtime_min.rs

@@ -4,6 +4,9 @@ use std::time::{SystemTime, UNIX_EPOCH};
 use serde::Serialize;
 
 use crate::config::ProxyConfig;
+use crate::stats::{
+    MeWriterCleanupSideEffectStep, MeWriterTeardownMode, MeWriterTeardownReason, Stats,
+};
 
 use super::ApiShared;
 
@@ -98,6 +101,50 @@ pub(super) struct RuntimeMeQualityCountersData {
     pub(super) reconnect_success_total: u64,
 }
 
+#[derive(Serialize)]
+pub(super) struct RuntimeMeQualityTeardownAttemptData {
+    pub(super) reason: &'static str,
+    pub(super) mode: &'static str,
+    pub(super) total: u64,
+}
+
+#[derive(Serialize)]
+pub(super) struct RuntimeMeQualityTeardownSuccessData {
+    pub(super) mode: &'static str,
+    pub(super) total: u64,
+}
+
+#[derive(Serialize)]
+pub(super) struct RuntimeMeQualityTeardownSideEffectData {
+    pub(super) step: &'static str,
+    pub(super) total: u64,
+}
+
+#[derive(Serialize)]
+pub(super) struct RuntimeMeQualityTeardownDurationBucketData {
+    pub(super) le_seconds: &'static str,
+    pub(super) total: u64,
+}
+
+#[derive(Serialize)]
+pub(super) struct RuntimeMeQualityTeardownDurationData {
+    pub(super) mode: &'static str,
+    pub(super) count: u64,
+    pub(super) sum_seconds: f64,
+    pub(super) buckets: Vec<RuntimeMeQualityTeardownDurationBucketData>,
+}
+
+#[derive(Serialize)]
+pub(super) struct RuntimeMeQualityTeardownData {
+    pub(super) attempts: Vec<RuntimeMeQualityTeardownAttemptData>,
+    pub(super) success: Vec<RuntimeMeQualityTeardownSuccessData>,
+    pub(super) timeout_total: u64,
+    pub(super) escalation_total: u64,
+    pub(super) noop_total: u64,
+    pub(super) cleanup_side_effect_failures: Vec<RuntimeMeQualityTeardownSideEffectData>,
+    pub(super) duration: Vec<RuntimeMeQualityTeardownDurationData>,
+}
+
 #[derive(Serialize)]
 pub(super) struct RuntimeMeQualityRouteDropData {
     pub(super) no_conn_total: u64,
@@ -107,6 +154,25 @@ pub(super) struct RuntimeMeQualityRouteDropData {
     pub(super) queue_full_high_total: u64,
 }
 
+#[derive(Serialize)]
+pub(super) struct RuntimeMeQualityFamilyStateData {
+    pub(super) family: &'static str,
+    pub(super) state: &'static str,
+    pub(super) state_since_epoch_secs: u64,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub(super) suppressed_until_epoch_secs: Option<u64>,
+    pub(super) fail_streak: u32,
+    pub(super) recover_success_streak: u32,
+}
+
+#[derive(Serialize)]
+pub(super) struct RuntimeMeQualityDrainGateData {
+    pub(super) route_quorum_ok: bool,
+    pub(super) redundancy_ok: bool,
+    pub(super) block_reason: &'static str,
+    pub(super) updated_at_epoch_secs: u64,
+}
+
 #[derive(Serialize)]
 pub(super) struct RuntimeMeQualityDcRttData {
     pub(super) dc: i16,
@@ -120,7 +186,10 @@ pub(super) struct RuntimeMeQualityDcRttData {
 #[derive(Serialize)]
 pub(super) struct RuntimeMeQualityPayload {
     pub(super) counters: RuntimeMeQualityCountersData,
+    pub(super) teardown: RuntimeMeQualityTeardownData,
     pub(super) route_drops: RuntimeMeQualityRouteDropData,
+    pub(super) family_states: Vec<RuntimeMeQualityFamilyStateData>,
+    pub(super) drain_gate: RuntimeMeQualityDrainGateData,
     pub(super) dc_rtt: Vec<RuntimeMeQualityDcRttData>,
 }
 
@@ -361,6 +430,19 @@ pub(super) async fn build_runtime_me_quality_data(shared: &ApiShared) -> Runtime
     };
 
     let status = pool.api_status_snapshot().await;
+    let family_states = pool
+        .api_family_state_snapshot()
+        .into_iter()
+        .map(|entry| RuntimeMeQualityFamilyStateData {
+            family: entry.family,
+            state: entry.state,
+            state_since_epoch_secs: entry.state_since_epoch_secs,
+            suppressed_until_epoch_secs: entry.suppressed_until_epoch_secs,
+            fail_streak: entry.fail_streak,
+            recover_success_streak: entry.recover_success_streak,
+        })
+        .collect();
+    let drain_gate_snapshot = pool.api_drain_gate_snapshot();
     RuntimeMeQualityData {
         enabled: true,
         reason: None,
@@ -374,6 +456,7 @@ pub(super) async fn build_runtime_me_quality_data(shared: &ApiShared) -> Runtime
                 reconnect_attempt_total: shared.stats.get_me_reconnect_attempts(),
                 reconnect_success_total: shared.stats.get_me_reconnect_success(),
             },
+            teardown: build_runtime_me_teardown_data(shared),
             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(),
@@ -381,6 +464,13 @@ pub(super) async fn build_runtime_me_quality_data(shared: &ApiShared) -> Runtime
                 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(),
             },
+            family_states,
+            drain_gate: RuntimeMeQualityDrainGateData {
+                route_quorum_ok: drain_gate_snapshot.route_quorum_ok,
+                redundancy_ok: drain_gate_snapshot.redundancy_ok,
+                block_reason: drain_gate_snapshot.block_reason,
+                updated_at_epoch_secs: drain_gate_snapshot.updated_at_epoch_secs,
+            },
             dc_rtt: status
                 .dcs
                 .into_iter()
@@ -397,6 +487,81 @@ pub(super) async fn build_runtime_me_quality_data(shared: &ApiShared) -> Runtime
     }
 }
 
+fn build_runtime_me_teardown_data(shared: &ApiShared) -> RuntimeMeQualityTeardownData {
+    let attempts = MeWriterTeardownReason::ALL
+        .iter()
+        .copied()
+        .flat_map(|reason| {
+            MeWriterTeardownMode::ALL
+                .iter()
+                .copied()
+                .map(move |mode| RuntimeMeQualityTeardownAttemptData {
+                    reason: reason.as_str(),
+                    mode: mode.as_str(),
+                    total: shared.stats.get_me_writer_teardown_attempt_total(reason, mode),
+                })
+        })
+        .collect();
+
+    let success = MeWriterTeardownMode::ALL
+        .iter()
+        .copied()
+        .map(|mode| RuntimeMeQualityTeardownSuccessData {
+            mode: mode.as_str(),
+            total: shared.stats.get_me_writer_teardown_success_total(mode),
+        })
+        .collect();
+
+    let cleanup_side_effect_failures = MeWriterCleanupSideEffectStep::ALL
+        .iter()
+        .copied()
+        .map(|step| RuntimeMeQualityTeardownSideEffectData {
+            step: step.as_str(),
+            total: shared
+                .stats
+                .get_me_writer_cleanup_side_effect_failures_total(step),
+        })
+        .collect();
+
+    let duration = MeWriterTeardownMode::ALL
+        .iter()
+        .copied()
+        .map(|mode| {
+            let count = shared.stats.get_me_writer_teardown_duration_count(mode);
+            let mut buckets: Vec<RuntimeMeQualityTeardownDurationBucketData> = Stats::me_writer_teardown_duration_bucket_labels()
+                .iter()
+                .enumerate()
+                .map(|(bucket_idx, label)| RuntimeMeQualityTeardownDurationBucketData {
+                    le_seconds: label,
+                    total: shared
+                        .stats
+                        .get_me_writer_teardown_duration_bucket_total(mode, bucket_idx),
+                })
+                .collect();
+            buckets.push(RuntimeMeQualityTeardownDurationBucketData {
+                le_seconds: "+Inf",
+                total: count,
+            });
+            RuntimeMeQualityTeardownDurationData {
+                mode: mode.as_str(),
+                count,
+                sum_seconds: shared.stats.get_me_writer_teardown_duration_sum_seconds(mode),
+                buckets,
+            }
+        })
+        .collect();
+
+    RuntimeMeQualityTeardownData {
+        attempts,
+        success,
+        timeout_total: shared.stats.get_me_writer_teardown_timeout_total(),
+        escalation_total: shared.stats.get_me_writer_teardown_escalation_total(),
+        noop_total: shared.stats.get_me_writer_teardown_noop_total(),
+        cleanup_side_effect_failures,
+        duration,
+    }
+}
+
 pub(super) async fn build_runtime_upstream_quality_data(
     shared: &ApiShared,
 ) -> RuntimeUpstreamQualityData {

src/api/runtime_stats.rs

@@ -1,7 +1,7 @@
 use std::time::{Duration, Instant, SystemTime, UNIX_EPOCH};
 
 use crate::config::ApiConfig;
-use crate::stats::Stats;
+use crate::stats::{MeWriterTeardownMode, Stats};
 use crate::transport::upstream::IpPreference;
 use crate::transport::UpstreamRouteKind;
 
@@ -106,6 +106,29 @@ pub(super) fn build_zero_all_data(stats: &Stats, configured_users: usize) -> Zer
             refill_failed_total: stats.get_me_refill_failed_total(),
             writer_restored_same_endpoint_total: stats.get_me_writer_restored_same_endpoint_total(),
             writer_restored_fallback_total: stats.get_me_writer_restored_fallback_total(),
+            teardown_attempt_total_normal: stats
+                .get_me_writer_teardown_attempt_total_by_mode(MeWriterTeardownMode::Normal),
+            teardown_attempt_total_hard_detach: stats
+                .get_me_writer_teardown_attempt_total_by_mode(MeWriterTeardownMode::HardDetach),
+            teardown_success_total_normal: stats
+                .get_me_writer_teardown_success_total(MeWriterTeardownMode::Normal),
+            teardown_success_total_hard_detach: stats
+                .get_me_writer_teardown_success_total(MeWriterTeardownMode::HardDetach),
+            teardown_timeout_total: stats.get_me_writer_teardown_timeout_total(),
+            teardown_escalation_total: stats.get_me_writer_teardown_escalation_total(),
+            teardown_noop_total: stats.get_me_writer_teardown_noop_total(),
+            teardown_cleanup_side_effect_failures_total: stats
+                .get_me_writer_cleanup_side_effect_failures_total_all(),
+            teardown_duration_count_total: stats
+                .get_me_writer_teardown_duration_count(MeWriterTeardownMode::Normal)
+                .saturating_add(
+                    stats.get_me_writer_teardown_duration_count(MeWriterTeardownMode::HardDetach),
+                ),
+            teardown_duration_sum_seconds_total: stats
+                .get_me_writer_teardown_duration_sum_seconds(MeWriterTeardownMode::Normal)
+                + stats.get_me_writer_teardown_duration_sum_seconds(
+                    MeWriterTeardownMode::HardDetach,
+                ),
         },
         desync: ZeroDesyncData {
             secure_padding_invalid_total: stats.get_secure_padding_invalid(),

src/config/defaults.rs

@@ -65,6 +65,10 @@ pub(crate) fn default_tls_domain() -> String {
     "petrovich.ru".to_string()
 }
 
+pub(crate) fn default_tls_fetch_scope() -> String {
+    String::new()
+}
+
 pub(crate) fn default_mask_port() -> u16 {
     443
 }

src/config/hot_reload.rs

@@ -623,6 +623,7 @@ fn warn_non_hot_changes(old: &ProxyConfig, new: &ProxyConfig, non_hot_changed: b
     }
     if old.censorship.tls_domain != new.censorship.tls_domain
         || old.censorship.tls_domains != new.censorship.tls_domains
+        || old.censorship.tls_fetch_scope != new.censorship.tls_fetch_scope
         || old.censorship.mask != new.censorship.mask
         || old.censorship.mask_host != new.censorship.mask_host
         || old.censorship.mask_port != new.censorship.mask_port

src/config/load.rs

@@ -779,6 +779,9 @@ impl ProxyConfig {
             config.censorship.mask_host = Some(config.censorship.tls_domain.clone());
         }
 
+        // Normalize optional TLS fetch scope: whitespace-only values disable scoped routing.
+        config.censorship.tls_fetch_scope = config.censorship.tls_fetch_scope.trim().to_string();
+
         // Merge primary + extra TLS domains, deduplicate (primary always first).
         if !config.censorship.tls_domains.is_empty() {
             let mut all = Vec::with_capacity(1 + config.censorship.tls_domains.len());
@@ -2097,6 +2100,59 @@ mod tests {
         let _ = std::fs::remove_file(path);
     }
 
+    #[test]
+    fn tls_fetch_scope_default_is_empty() {
+        let toml = r#"
+            [censorship]
+            tls_domain = "example.com"
+
+            [access.users]
+            user = "00000000000000000000000000000000"
+        "#;
+        let dir = std::env::temp_dir();
+        let path = dir.join("telemt_tls_fetch_scope_default_test.toml");
+        std::fs::write(&path, toml).unwrap();
+        let cfg = ProxyConfig::load(&path).unwrap();
+        assert!(cfg.censorship.tls_fetch_scope.is_empty());
+        let _ = std::fs::remove_file(path);
+    }
+
+    #[test]
+    fn tls_fetch_scope_is_trimmed_during_load() {
+        let toml = r#"
+            [censorship]
+            tls_domain = "example.com"
+            tls_fetch_scope = "  me  "
+
+            [access.users]
+            user = "00000000000000000000000000000000"
+        "#;
+        let dir = std::env::temp_dir();
+        let path = dir.join("telemt_tls_fetch_scope_trim_test.toml");
+        std::fs::write(&path, toml).unwrap();
+        let cfg = ProxyConfig::load(&path).unwrap();
+        assert_eq!(cfg.censorship.tls_fetch_scope, "me");
+        let _ = std::fs::remove_file(path);
+    }
+
+    #[test]
+    fn tls_fetch_scope_whitespace_becomes_empty() {
+        let toml = r#"
+            [censorship]
+            tls_domain = "example.com"
+            tls_fetch_scope = "   "
+
+            [access.users]
+            user = "00000000000000000000000000000000"
+        "#;
+        let dir = std::env::temp_dir();
+        let path = dir.join("telemt_tls_fetch_scope_blank_test.toml");
+        std::fs::write(&path, toml).unwrap();
+        let cfg = ProxyConfig::load(&path).unwrap();
+        assert!(cfg.censorship.tls_fetch_scope.is_empty());
+        let _ = std::fs::remove_file(path);
+    }
+
     #[test]
     fn invalid_ad_tag_is_disabled_during_load() {
         let toml = r#"

src/config/types.rs

@@ -1308,6 +1308,11 @@ pub struct AntiCensorshipConfig {
     #[serde(default)]
     pub tls_domains: Vec<String>,
 
+    /// Upstream scope used for TLS front metadata fetches.
+    /// Empty value keeps default upstream routing behavior.
+    #[serde(default = "default_tls_fetch_scope")]
+    pub tls_fetch_scope: String,
+
     #[serde(default = "default_true")]
     pub mask: bool,
 
@@ -1365,6 +1370,7 @@ impl Default for AntiCensorshipConfig {
         Self {
             tls_domain: default_tls_domain(),
             tls_domains: Vec::new(),
+            tls_fetch_scope: default_tls_fetch_scope(),
             mask: default_true(),
             mask_host: None,
             mask_port: default_mask_port(),

src/maestro/tls_bootstrap.rs

@@ -38,12 +38,15 @@ pub(crate) async fn bootstrap_tls_front(
             .clone()
             .unwrap_or_else(|| config.censorship.tls_domain.clone());
         let mask_unix_sock = config.censorship.mask_unix_sock.clone();
+        let tls_fetch_scope = (!config.censorship.tls_fetch_scope.is_empty())
+            .then(|| config.censorship.tls_fetch_scope.clone());
         let fetch_timeout = Duration::from_secs(5);
 
         let cache_initial = cache.clone();
         let domains_initial = tls_domains.to_vec();
         let host_initial = mask_host.clone();
         let unix_sock_initial = mask_unix_sock.clone();
+        let scope_initial = tls_fetch_scope.clone();
         let upstream_initial = upstream_manager.clone();
         tokio::spawn(async move {
             let mut join = tokio::task::JoinSet::new();
@@ -51,6 +54,7 @@ pub(crate) async fn bootstrap_tls_front(
                 let cache_domain = cache_initial.clone();
                 let host_domain = host_initial.clone();
                 let unix_sock_domain = unix_sock_initial.clone();
+                let scope_domain = scope_initial.clone();
                 let upstream_domain = upstream_initial.clone();
                 join.spawn(async move {
                     match crate::tls_front::fetcher::fetch_real_tls(
@@ -59,6 +63,7 @@ pub(crate) async fn bootstrap_tls_front(
                         &domain,
                         fetch_timeout,
                         Some(upstream_domain),
+                        scope_domain.as_deref(),
                         proxy_protocol,
                         unix_sock_domain.as_deref(),
                     )
@@ -100,6 +105,7 @@ pub(crate) async fn bootstrap_tls_front(
         let domains_refresh = tls_domains.to_vec();
         let host_refresh = mask_host.clone();
         let unix_sock_refresh = mask_unix_sock.clone();
+        let scope_refresh = tls_fetch_scope.clone();
         let upstream_refresh = upstream_manager.clone();
         tokio::spawn(async move {
             loop {
@@ -112,6 +118,7 @@ pub(crate) async fn bootstrap_tls_front(
                     let cache_domain = cache_refresh.clone();
                     let host_domain = host_refresh.clone();
                     let unix_sock_domain = unix_sock_refresh.clone();
+                    let scope_domain = scope_refresh.clone();
                     let upstream_domain = upstream_refresh.clone();
                     join.spawn(async move {
                         match crate::tls_front::fetcher::fetch_real_tls(
@@ -120,6 +127,7 @@ pub(crate) async fn bootstrap_tls_front(
                             &domain,
                             fetch_timeout,
                             Some(upstream_domain),
+                            scope_domain.as_deref(),
                             proxy_protocol,
                             unix_sock_domain.as_deref(),
                         )

src/metrics.rs

@@ -16,7 +16,9 @@ use tracing::{info, warn, debug};
 use crate::config::ProxyConfig;
 use crate::ip_tracker::UserIpTracker;
 use crate::stats::beobachten::BeobachtenStore;
-use crate::stats::Stats;
+use crate::stats::{
+    MeWriterCleanupSideEffectStep, MeWriterTeardownMode, MeWriterTeardownReason, Stats,
+};
 use crate::transport::{ListenOptions, create_listener};
 
 pub async fn serve(
@@ -1770,6 +1772,169 @@ async fn render_metrics(stats: &Stats, config: &ProxyConfig, ip_tracker: &UserIp
         }
     );
 
+    let _ = writeln!(
+        out,
+        "# HELP telemt_me_writer_teardown_attempt_total ME writer teardown attempts by reason and mode"
+    );
+    let _ = writeln!(out, "# TYPE telemt_me_writer_teardown_attempt_total counter");
+    for reason in MeWriterTeardownReason::ALL {
+        for mode in MeWriterTeardownMode::ALL {
+            let _ = writeln!(
+                out,
+                "telemt_me_writer_teardown_attempt_total{{reason=\"{}\",mode=\"{}\"}} {}",
+                reason.as_str(),
+                mode.as_str(),
+                if me_allows_normal {
+                    stats.get_me_writer_teardown_attempt_total(reason, mode)
+                } else {
+                    0
+                }
+            );
+        }
+    }
+
+    let _ = writeln!(
+        out,
+        "# HELP telemt_me_writer_teardown_success_total ME writer teardown successes by mode"
+    );
+    let _ = writeln!(out, "# TYPE telemt_me_writer_teardown_success_total counter");
+    for mode in MeWriterTeardownMode::ALL {
+        let _ = writeln!(
+            out,
+            "telemt_me_writer_teardown_success_total{{mode=\"{}\"}} {}",
+            mode.as_str(),
+            if me_allows_normal {
+                stats.get_me_writer_teardown_success_total(mode)
+            } else {
+                0
+            }
+        );
+    }
+
+    let _ = writeln!(
+        out,
+        "# HELP telemt_me_writer_teardown_timeout_total Teardown operations that timed out"
+    );
+    let _ = writeln!(out, "# TYPE telemt_me_writer_teardown_timeout_total counter");
+    let _ = writeln!(
+        out,
+        "telemt_me_writer_teardown_timeout_total {}",
+        if me_allows_normal {
+            stats.get_me_writer_teardown_timeout_total()
+        } else {
+            0
+        }
+    );
+
+    let _ = writeln!(
+        out,
+        "# HELP telemt_me_writer_teardown_escalation_total Watchdog teardown escalations to hard detach"
+    );
+    let _ = writeln!(
+        out,
+        "# TYPE telemt_me_writer_teardown_escalation_total counter"
+    );
+    let _ = writeln!(
+        out,
+        "telemt_me_writer_teardown_escalation_total {}",
+        if me_allows_normal {
+            stats.get_me_writer_teardown_escalation_total()
+        } else {
+            0
+        }
+    );
+
+    let _ = writeln!(
+        out,
+        "# HELP telemt_me_writer_teardown_noop_total Teardown operations that became no-op"
+    );
+    let _ = writeln!(out, "# TYPE telemt_me_writer_teardown_noop_total counter");
+    let _ = writeln!(
+        out,
+        "telemt_me_writer_teardown_noop_total {}",
+        if me_allows_normal {
+            stats.get_me_writer_teardown_noop_total()
+        } else {
+            0
+        }
+    );
+
+    let _ = writeln!(
+        out,
+        "# HELP telemt_me_writer_teardown_duration_seconds ME writer teardown latency histogram by mode"
+    );
+    let _ = writeln!(
+        out,
+        "# TYPE telemt_me_writer_teardown_duration_seconds histogram"
+    );
+    let bucket_labels = Stats::me_writer_teardown_duration_bucket_labels();
+    for mode in MeWriterTeardownMode::ALL {
+        for (bucket_idx, label) in bucket_labels.iter().enumerate() {
+            let _ = writeln!(
+                out,
+                "telemt_me_writer_teardown_duration_seconds_bucket{{mode=\"{}\",le=\"{}\"}} {}",
+                mode.as_str(),
+                label,
+                if me_allows_normal {
+                    stats.get_me_writer_teardown_duration_bucket_total(mode, bucket_idx)
+                } else {
+                    0
+                }
+            );
+        }
+        let _ = writeln!(
+            out,
+            "telemt_me_writer_teardown_duration_seconds_bucket{{mode=\"{}\",le=\"+Inf\"}} {}",
+            mode.as_str(),
+            if me_allows_normal {
+                stats.get_me_writer_teardown_duration_count(mode)
+            } else {
+                0
+            }
+        );
+        let _ = writeln!(
+            out,
+            "telemt_me_writer_teardown_duration_seconds_sum{{mode=\"{}\"}} {:.6}",
+            mode.as_str(),
+            if me_allows_normal {
+                stats.get_me_writer_teardown_duration_sum_seconds(mode)
+            } else {
+                0.0
+            }
+        );
+        let _ = writeln!(
+            out,
+            "telemt_me_writer_teardown_duration_seconds_count{{mode=\"{}\"}} {}",
+            mode.as_str(),
+            if me_allows_normal {
+                stats.get_me_writer_teardown_duration_count(mode)
+            } else {
+                0
+            }
+        );
+    }
+
+    let _ = writeln!(
+        out,
+        "# HELP telemt_me_writer_cleanup_side_effect_failures_total Failed cleanup side effects by step"
+    );
+    let _ = writeln!(
+        out,
+        "# TYPE telemt_me_writer_cleanup_side_effect_failures_total counter"
+    );
+    for step in MeWriterCleanupSideEffectStep::ALL {
+        let _ = writeln!(
+            out,
+            "telemt_me_writer_cleanup_side_effect_failures_total{{step=\"{}\"}} {}",
+            step.as_str(),
+            if me_allows_normal {
+                stats.get_me_writer_cleanup_side_effect_failures_total(step)
+            } else {
+                0
+            }
+        );
+    }
+
     let _ = writeln!(out, "# HELP telemt_me_refill_triggered_total Immediate ME refill runs started");
     let _ = writeln!(out, "# TYPE telemt_me_refill_triggered_total counter");
     let _ = writeln!(
@@ -2175,6 +2340,17 @@ mod tests {
         assert!(output.contains("# TYPE telemt_me_rpc_proxy_req_signal_sent_total counter"));
         assert!(output.contains("# TYPE telemt_me_idle_close_by_peer_total counter"));
         assert!(output.contains("# TYPE telemt_me_writer_removed_total counter"));
+        assert!(output.contains("# TYPE telemt_me_writer_teardown_attempt_total counter"));
+        assert!(output.contains("# TYPE telemt_me_writer_teardown_success_total counter"));
+        assert!(output.contains("# TYPE telemt_me_writer_teardown_timeout_total counter"));
+        assert!(output.contains("# TYPE telemt_me_writer_teardown_escalation_total counter"));
+        assert!(output.contains("# TYPE telemt_me_writer_teardown_noop_total counter"));
+        assert!(output.contains(
+            "# TYPE telemt_me_writer_teardown_duration_seconds histogram"
+        ));
+        assert!(output.contains(
+            "# TYPE telemt_me_writer_cleanup_side_effect_failures_total counter"
+        ));
         assert!(output.contains("# TYPE telemt_me_writer_close_signal_drop_total counter"));
         assert!(output.contains(
             "# TYPE telemt_me_writer_close_signal_channel_full_total counter"

src/stats/mod.rs

@@ -19,6 +19,137 @@ use tracing::debug;
 use crate::config::{MeTelemetryLevel, MeWriterPickMode};
 use self::telemetry::TelemetryPolicy;
 
+const ME_WRITER_TEARDOWN_MODE_COUNT: usize = 2;
+const ME_WRITER_TEARDOWN_REASON_COUNT: usize = 11;
+const ME_WRITER_CLEANUP_SIDE_EFFECT_STEP_COUNT: usize = 2;
+const ME_WRITER_TEARDOWN_DURATION_BUCKET_COUNT: usize = 12;
+const ME_WRITER_TEARDOWN_DURATION_BUCKET_BOUNDS_MICROS: [u64; ME_WRITER_TEARDOWN_DURATION_BUCKET_COUNT] = [
+    1_000,
+    5_000,
+    10_000,
+    25_000,
+    50_000,
+    100_000,
+    250_000,
+    500_000,
+    1_000_000,
+    2_500_000,
+    5_000_000,
+    10_000_000,
+];
+const ME_WRITER_TEARDOWN_DURATION_BUCKET_LABELS: [&str; ME_WRITER_TEARDOWN_DURATION_BUCKET_COUNT] = [
+    "0.001",
+    "0.005",
+    "0.01",
+    "0.025",
+    "0.05",
+    "0.1",
+    "0.25",
+    "0.5",
+    "1",
+    "2.5",
+    "5",
+    "10",
+];
+
+#[derive(Clone, Copy, Debug, PartialEq, Eq, Hash)]
+#[repr(u8)]
+pub enum MeWriterTeardownMode {
+    Normal = 0,
+    HardDetach = 1,
+}
+
+impl MeWriterTeardownMode {
+    pub const ALL: [Self; ME_WRITER_TEARDOWN_MODE_COUNT] =
+        [Self::Normal, Self::HardDetach];
+
+    pub const fn as_str(self) -> &'static str {
+        match self {
+            Self::Normal => "normal",
+            Self::HardDetach => "hard_detach",
+        }
+    }
+
+    const fn idx(self) -> usize {
+        self as usize
+    }
+}
+
+#[derive(Clone, Copy, Debug, PartialEq, Eq, Hash)]
+#[repr(u8)]
+pub enum MeWriterTeardownReason {
+    ReaderExit = 0,
+    WriterTaskExit = 1,
+    PingSendFail = 2,
+    SignalSendFail = 3,
+    RouteChannelClosed = 4,
+    CloseRpcChannelClosed = 5,
+    PruneClosedWriter = 6,
+    ReapTimeoutExpired = 7,
+    ReapThresholdForce = 8,
+    ReapEmpty = 9,
+    WatchdogStuckDraining = 10,
+}
+
+impl MeWriterTeardownReason {
+    pub const ALL: [Self; ME_WRITER_TEARDOWN_REASON_COUNT] = [
+        Self::ReaderExit,
+        Self::WriterTaskExit,
+        Self::PingSendFail,
+        Self::SignalSendFail,
+        Self::RouteChannelClosed,
+        Self::CloseRpcChannelClosed,
+        Self::PruneClosedWriter,
+        Self::ReapTimeoutExpired,
+        Self::ReapThresholdForce,
+        Self::ReapEmpty,
+        Self::WatchdogStuckDraining,
+    ];
+
+    pub const fn as_str(self) -> &'static str {
+        match self {
+            Self::ReaderExit => "reader_exit",
+            Self::WriterTaskExit => "writer_task_exit",
+            Self::PingSendFail => "ping_send_fail",
+            Self::SignalSendFail => "signal_send_fail",
+            Self::RouteChannelClosed => "route_channel_closed",
+            Self::CloseRpcChannelClosed => "close_rpc_channel_closed",
+            Self::PruneClosedWriter => "prune_closed_writer",
+            Self::ReapTimeoutExpired => "reap_timeout_expired",
+            Self::ReapThresholdForce => "reap_threshold_force",
+            Self::ReapEmpty => "reap_empty",
+            Self::WatchdogStuckDraining => "watchdog_stuck_draining",
+        }
+    }
+
+    const fn idx(self) -> usize {
+        self as usize
+    }
+}
+
+#[derive(Clone, Copy, Debug, PartialEq, Eq, Hash)]
+#[repr(u8)]
+pub enum MeWriterCleanupSideEffectStep {
+    CloseSignalChannelFull = 0,
+    CloseSignalChannelClosed = 1,
+}
+
+impl MeWriterCleanupSideEffectStep {
+    pub const ALL: [Self; ME_WRITER_CLEANUP_SIDE_EFFECT_STEP_COUNT] =
+        [Self::CloseSignalChannelFull, Self::CloseSignalChannelClosed];
+
+    pub const fn as_str(self) -> &'static str {
+        match self {
+            Self::CloseSignalChannelFull => "close_signal_channel_full",
+            Self::CloseSignalChannelClosed => "close_signal_channel_closed",
+        }
+    }
+
+    const fn idx(self) -> usize {
+        self as usize
+    }
+}
+
 // ============= Stats =============
 
 #[derive(Default)]
@@ -128,6 +259,18 @@ pub struct Stats {
     me_draining_writers_reap_progress_total: AtomicU64,
     me_writer_removed_total: AtomicU64,
     me_writer_removed_unexpected_total: AtomicU64,
+    me_writer_teardown_attempt_total:
+        [[AtomicU64; ME_WRITER_TEARDOWN_MODE_COUNT]; ME_WRITER_TEARDOWN_REASON_COUNT],
+    me_writer_teardown_success_total: [AtomicU64; ME_WRITER_TEARDOWN_MODE_COUNT],
+    me_writer_teardown_timeout_total: AtomicU64,
+    me_writer_teardown_escalation_total: AtomicU64,
+    me_writer_teardown_noop_total: AtomicU64,
+    me_writer_cleanup_side_effect_failures_total:
+        [AtomicU64; ME_WRITER_CLEANUP_SIDE_EFFECT_STEP_COUNT],
+    me_writer_teardown_duration_bucket_hits:
+        [[AtomicU64; ME_WRITER_TEARDOWN_DURATION_BUCKET_COUNT + 1]; ME_WRITER_TEARDOWN_MODE_COUNT],
+    me_writer_teardown_duration_sum_micros: [AtomicU64; ME_WRITER_TEARDOWN_MODE_COUNT],
+    me_writer_teardown_duration_count: [AtomicU64; ME_WRITER_TEARDOWN_MODE_COUNT],
     me_refill_triggered_total: AtomicU64,
     me_refill_skipped_inflight_total: AtomicU64,
     me_refill_failed_total: AtomicU64,
@@ -765,6 +908,74 @@ impl Stats {
             self.me_writer_removed_unexpected_total.fetch_add(1, Ordering::Relaxed);
         }
     }
+    pub fn increment_me_writer_teardown_attempt_total(
+        &self,
+        reason: MeWriterTeardownReason,
+        mode: MeWriterTeardownMode,
+    ) {
+        if self.telemetry_me_allows_normal() {
+            self.me_writer_teardown_attempt_total[reason.idx()][mode.idx()]
+                .fetch_add(1, Ordering::Relaxed);
+        }
+    }
+    pub fn increment_me_writer_teardown_success_total(&self, mode: MeWriterTeardownMode) {
+        if self.telemetry_me_allows_normal() {
+            self.me_writer_teardown_success_total[mode.idx()].fetch_add(1, Ordering::Relaxed);
+        }
+    }
+    pub fn increment_me_writer_teardown_timeout_total(&self) {
+        if self.telemetry_me_allows_normal() {
+            self.me_writer_teardown_timeout_total
+                .fetch_add(1, Ordering::Relaxed);
+        }
+    }
+    pub fn increment_me_writer_teardown_escalation_total(&self) {
+        if self.telemetry_me_allows_normal() {
+            self.me_writer_teardown_escalation_total
+                .fetch_add(1, Ordering::Relaxed);
+        }
+    }
+    pub fn increment_me_writer_teardown_noop_total(&self) {
+        if self.telemetry_me_allows_normal() {
+            self.me_writer_teardown_noop_total
+                .fetch_add(1, Ordering::Relaxed);
+        }
+    }
+    pub fn increment_me_writer_cleanup_side_effect_failures_total(
+        &self,
+        step: MeWriterCleanupSideEffectStep,
+    ) {
+        if self.telemetry_me_allows_normal() {
+            self.me_writer_cleanup_side_effect_failures_total[step.idx()]
+                .fetch_add(1, Ordering::Relaxed);
+        }
+    }
+    pub fn observe_me_writer_teardown_duration(
+        &self,
+        mode: MeWriterTeardownMode,
+        duration: Duration,
+    ) {
+        if !self.telemetry_me_allows_normal() {
+            return;
+        }
+        let duration_micros = duration.as_micros().min(u64::MAX as u128) as u64;
+        let mut bucket_idx = ME_WRITER_TEARDOWN_DURATION_BUCKET_COUNT;
+        for (idx, upper_bound_micros) in ME_WRITER_TEARDOWN_DURATION_BUCKET_BOUNDS_MICROS
+            .iter()
+            .copied()
+            .enumerate()
+        {
+            if duration_micros <= upper_bound_micros {
+                bucket_idx = idx;
+                break;
+            }
+        }
+        self.me_writer_teardown_duration_bucket_hits[mode.idx()][bucket_idx]
+            .fetch_add(1, Ordering::Relaxed);
+        self.me_writer_teardown_duration_sum_micros[mode.idx()]
+            .fetch_add(duration_micros, Ordering::Relaxed);
+        self.me_writer_teardown_duration_count[mode.idx()].fetch_add(1, Ordering::Relaxed);
+    }
     pub fn increment_me_refill_triggered_total(&self) {
         if self.telemetry_me_allows_debug() {
             self.me_refill_triggered_total.fetch_add(1, Ordering::Relaxed);
@@ -1297,6 +1508,79 @@ impl Stats {
     pub fn get_me_writer_removed_unexpected_total(&self) -> u64 {
         self.me_writer_removed_unexpected_total.load(Ordering::Relaxed)
     }
+    pub fn get_me_writer_teardown_attempt_total(
+        &self,
+        reason: MeWriterTeardownReason,
+        mode: MeWriterTeardownMode,
+    ) -> u64 {
+        self.me_writer_teardown_attempt_total[reason.idx()][mode.idx()]
+            .load(Ordering::Relaxed)
+    }
+    pub fn get_me_writer_teardown_attempt_total_by_mode(&self, mode: MeWriterTeardownMode) -> u64 {
+        MeWriterTeardownReason::ALL
+            .iter()
+            .copied()
+            .map(|reason| self.get_me_writer_teardown_attempt_total(reason, mode))
+            .sum()
+    }
+    pub fn get_me_writer_teardown_success_total(&self, mode: MeWriterTeardownMode) -> u64 {
+        self.me_writer_teardown_success_total[mode.idx()].load(Ordering::Relaxed)
+    }
+    pub fn get_me_writer_teardown_timeout_total(&self) -> u64 {
+        self.me_writer_teardown_timeout_total.load(Ordering::Relaxed)
+    }
+    pub fn get_me_writer_teardown_escalation_total(&self) -> u64 {
+        self.me_writer_teardown_escalation_total
+            .load(Ordering::Relaxed)
+    }
+    pub fn get_me_writer_teardown_noop_total(&self) -> u64 {
+        self.me_writer_teardown_noop_total.load(Ordering::Relaxed)
+    }
+    pub fn get_me_writer_cleanup_side_effect_failures_total(
+        &self,
+        step: MeWriterCleanupSideEffectStep,
+    ) -> u64 {
+        self.me_writer_cleanup_side_effect_failures_total[step.idx()]
+            .load(Ordering::Relaxed)
+    }
+    pub fn get_me_writer_cleanup_side_effect_failures_total_all(&self) -> u64 {
+        MeWriterCleanupSideEffectStep::ALL
+            .iter()
+            .copied()
+            .map(|step| self.get_me_writer_cleanup_side_effect_failures_total(step))
+            .sum()
+    }
+    pub fn me_writer_teardown_duration_bucket_labels(
+    ) -> &'static [&'static str; ME_WRITER_TEARDOWN_DURATION_BUCKET_COUNT] {
+        &ME_WRITER_TEARDOWN_DURATION_BUCKET_LABELS
+    }
+    pub fn get_me_writer_teardown_duration_bucket_hits(
+        &self,
+        mode: MeWriterTeardownMode,
+        bucket_idx: usize,
+    ) -> u64 {
+        self.me_writer_teardown_duration_bucket_hits[mode.idx()][bucket_idx]
+            .load(Ordering::Relaxed)
+    }
+    pub fn get_me_writer_teardown_duration_bucket_total(
+        &self,
+        mode: MeWriterTeardownMode,
+        bucket_idx: usize,
+    ) -> u64 {
+        let capped_idx = bucket_idx.min(ME_WRITER_TEARDOWN_DURATION_BUCKET_COUNT);
+        let mut total = 0u64;
+        for idx in 0..=capped_idx {
+            total = total.saturating_add(self.get_me_writer_teardown_duration_bucket_hits(mode, idx));
+        }
+        total
+    }
+    pub fn get_me_writer_teardown_duration_count(&self, mode: MeWriterTeardownMode) -> u64 {
+        self.me_writer_teardown_duration_count[mode.idx()].load(Ordering::Relaxed)
+    }
+    pub fn get_me_writer_teardown_duration_sum_seconds(&self, mode: MeWriterTeardownMode) -> f64 {
+        self.me_writer_teardown_duration_sum_micros[mode.idx()].load(Ordering::Relaxed) as f64
+            / 1_000_000.0
+    }
     pub fn get_me_refill_triggered_total(&self) -> u64 {
         self.me_refill_triggered_total.load(Ordering::Relaxed)
     }
@@ -1800,6 +2084,79 @@ mod tests {
         assert_eq!(stats.get_me_keepalive_sent(), 0);
         assert_eq!(stats.get_me_route_drop_queue_full(), 0);
     }
+
+    #[test]
+    fn test_teardown_counters_and_duration() {
+        let stats = Stats::new();
+        stats.increment_me_writer_teardown_attempt_total(
+            MeWriterTeardownReason::ReaderExit,
+            MeWriterTeardownMode::Normal,
+        );
+        stats.increment_me_writer_teardown_success_total(MeWriterTeardownMode::Normal);
+        stats.observe_me_writer_teardown_duration(
+            MeWriterTeardownMode::Normal,
+            Duration::from_millis(3),
+        );
+        stats.increment_me_writer_cleanup_side_effect_failures_total(
+            MeWriterCleanupSideEffectStep::CloseSignalChannelFull,
+        );
+
+        assert_eq!(
+            stats.get_me_writer_teardown_attempt_total(
+                MeWriterTeardownReason::ReaderExit,
+                MeWriterTeardownMode::Normal
+            ),
+            1
+        );
+        assert_eq!(
+            stats.get_me_writer_teardown_success_total(MeWriterTeardownMode::Normal),
+            1
+        );
+        assert_eq!(
+            stats.get_me_writer_teardown_duration_count(MeWriterTeardownMode::Normal),
+            1
+        );
+        assert!(
+            stats.get_me_writer_teardown_duration_sum_seconds(MeWriterTeardownMode::Normal) > 0.0
+        );
+        assert_eq!(
+            stats.get_me_writer_cleanup_side_effect_failures_total(
+                MeWriterCleanupSideEffectStep::CloseSignalChannelFull
+            ),
+            1
+        );
+    }
+
+    #[test]
+    fn test_teardown_counters_respect_me_silent() {
+        let stats = Stats::new();
+        stats.apply_telemetry_policy(TelemetryPolicy {
+            core_enabled: true,
+            user_enabled: true,
+            me_level: MeTelemetryLevel::Silent,
+        });
+        stats.increment_me_writer_teardown_attempt_total(
+            MeWriterTeardownReason::ReaderExit,
+            MeWriterTeardownMode::Normal,
+        );
+        stats.increment_me_writer_teardown_timeout_total();
+        stats.observe_me_writer_teardown_duration(
+            MeWriterTeardownMode::Normal,
+            Duration::from_millis(1),
+        );
+        assert_eq!(
+            stats.get_me_writer_teardown_attempt_total(
+                MeWriterTeardownReason::ReaderExit,
+                MeWriterTeardownMode::Normal
+            ),
+            0
+        );
+        assert_eq!(stats.get_me_writer_teardown_timeout_total(), 0);
+        assert_eq!(
+            stats.get_me_writer_teardown_duration_count(MeWriterTeardownMode::Normal),
+            0
+        );
+    }
     
     #[test]
     fn test_replay_checker_basic() {

src/tls_front/fetcher.rs

@@ -394,15 +394,17 @@ async fn connect_tcp_with_upstream(
     port: u16,
     connect_timeout: Duration,
     upstream: Option<std::sync::Arc<crate::transport::UpstreamManager>>,
+    scope: Option<&str>,
 ) -> Result<TcpStream> {
     if let Some(manager) = upstream {
         if let Some(addr) = resolve_socket_addr(host, port) {
-            match manager.connect(addr, None, None).await {
+            match manager.connect(addr, None, scope).await {
                 Ok(stream) => return Ok(stream),
                 Err(e) => {
                     warn!(
                         host = %host,
                         port = port,
+                        scope = ?scope,
                         error = %e,
                         "Upstream connect failed, using direct connect"
                     );
@@ -410,12 +412,13 @@ async fn connect_tcp_with_upstream(
             }
         } else if let Ok(mut addrs) = tokio::net::lookup_host((host, port)).await {
             if let Some(addr) = addrs.find(|a| a.is_ipv4()) {
-                match manager.connect(addr, None, None).await {
+                match manager.connect(addr, None, scope).await {
                     Ok(stream) => return Ok(stream),
                     Err(e) => {
                         warn!(
                             host = %host,
                             port = port,
+                            scope = ?scope,
                             error = %e,
                             "Upstream connect failed, using direct connect"
                         );
@@ -537,6 +540,7 @@ async fn fetch_via_raw_tls(
     sni: &str,
     connect_timeout: Duration,
     upstream: Option<std::sync::Arc<crate::transport::UpstreamManager>>,
+    scope: Option<&str>,
     proxy_protocol: u8,
     unix_sock: Option<&str>,
 ) -> Result<TlsFetchResult> {
@@ -572,7 +576,7 @@ async fn fetch_via_raw_tls(
     #[cfg(not(unix))]
     let _ = unix_sock;
 
-    let stream = connect_tcp_with_upstream(host, port, connect_timeout, upstream).await?;
+    let stream = connect_tcp_with_upstream(host, port, connect_timeout, upstream, scope).await?;
     fetch_via_raw_tls_stream(stream, sni, connect_timeout, proxy_protocol).await
 }
 
@@ -675,6 +679,7 @@ async fn fetch_via_rustls(
     sni: &str,
     connect_timeout: Duration,
     upstream: Option<std::sync::Arc<crate::transport::UpstreamManager>>,
+    scope: Option<&str>,
     proxy_protocol: u8,
     unix_sock: Option<&str>,
 ) -> Result<TlsFetchResult> {
@@ -710,7 +715,7 @@ async fn fetch_via_rustls(
     #[cfg(not(unix))]
     let _ = unix_sock;
 
-    let stream = connect_tcp_with_upstream(host, port, connect_timeout, upstream).await?;
+    let stream = connect_tcp_with_upstream(host, port, connect_timeout, upstream, scope).await?;
     fetch_via_rustls_stream(stream, host, sni, proxy_protocol).await
 }
 
@@ -726,6 +731,7 @@ pub async fn fetch_real_tls(
     sni: &str,
     connect_timeout: Duration,
     upstream: Option<std::sync::Arc<crate::transport::UpstreamManager>>,
+    scope: Option<&str>,
     proxy_protocol: u8,
     unix_sock: Option<&str>,
 ) -> Result<TlsFetchResult> {
@@ -735,6 +741,7 @@ pub async fn fetch_real_tls(
         sni,
         connect_timeout,
         upstream.clone(),
+        scope,
         proxy_protocol,
         unix_sock,
     )
@@ -753,6 +760,7 @@ pub async fn fetch_real_tls(
         sni,
         connect_timeout,
         upstream,
+        scope,
         proxy_protocol,
         unix_sock,
     )

src/transport/middle_proxy/health.rs

@@ -10,9 +10,10 @@ use tracing::{debug, info, warn};
 use crate::config::MeFloorMode;
 use crate::crypto::SecureRandom;
 use crate::network::IpFamily;
+use crate::stats::MeWriterTeardownReason;
 
 use super::MePool;
-use super::pool::MeWriter;
+use super::pool::{MeFamilyRuntimeState, MeWriter};
 
 const JITTER_FRAC_NUM: u64 = 2; // jitter up to 50% of backoff
 #[allow(dead_code)]
@@ -33,6 +34,33 @@ const HEALTH_DRAIN_SOFT_EVICT_BUDGET_MIN: usize = 8;
 const HEALTH_DRAIN_SOFT_EVICT_BUDGET_MAX: usize = 256;
 const HEALTH_DRAIN_REAP_OPPORTUNISTIC_INTERVAL_SECS: u64 = 1;
 const HEALTH_DRAIN_TIMEOUT_ENFORCER_INTERVAL_SECS: u64 = 1;
+const FAMILY_SUPPRESS_FAIL_STREAK_THRESHOLD: u32 = 6;
+const FAMILY_SUPPRESS_WINDOW_SECS: u64 = 120;
+const FAMILY_RECOVER_PROBE_INTERVAL_SECS: u64 = 5;
+const FAMILY_RECOVER_SUCCESS_STREAK_REQUIRED: u32 = 3;
+
+#[derive(Debug, Clone)]
+struct FamilyCircuitState {
+    state: MeFamilyRuntimeState,
+    state_since_at: Instant,
+    suppressed_until: Option<Instant>,
+    next_probe_at: Instant,
+    fail_streak: u32,
+    recover_success_streak: u32,
+}
+
+impl FamilyCircuitState {
+    fn new(now: Instant) -> Self {
+        Self {
+            state: MeFamilyRuntimeState::Healthy,
+            state_since_at: now,
+            suppressed_until: None,
+            next_probe_at: now,
+            fail_streak: 0,
+            recover_success_streak: 0,
+        }
+    }
+}
 
 #[derive(Debug, Clone)]
 struct DcFloorPlanEntry {
@@ -72,6 +100,25 @@ pub async fn me_health_monitor(pool: Arc<MePool>, rng: Arc<SecureRandom>, _min_c
     let mut floor_warn_next_allowed: HashMap<(i32, IpFamily), Instant> = HashMap::new();
     let mut drain_warn_next_allowed: HashMap<u64, Instant> = HashMap::new();
     let mut drain_soft_evict_next_allowed: HashMap<u64, Instant> = HashMap::new();
+    let mut family_v4_circuit = FamilyCircuitState::new(Instant::now());
+    let mut family_v6_circuit = FamilyCircuitState::new(Instant::now());
+    let init_epoch_secs = MePool::now_epoch_secs();
+    pool.set_family_runtime_state(
+        IpFamily::V4,
+        family_v4_circuit.state,
+        init_epoch_secs,
+        0,
+        family_v4_circuit.fail_streak,
+        family_v4_circuit.recover_success_streak,
+    );
+    pool.set_family_runtime_state(
+        IpFamily::V6,
+        family_v6_circuit.state,
+        init_epoch_secs,
+        0,
+        family_v6_circuit.fail_streak,
+        family_v6_circuit.recover_success_streak,
+    );
     let mut degraded_interval = true;
     loop {
         let interval = if degraded_interval {
@@ -87,7 +134,9 @@ pub async fn me_health_monitor(pool: Arc<MePool>, rng: Arc<SecureRandom>, _min_c
             &mut drain_soft_evict_next_allowed,
         )
         .await;
-        let v4_degraded = check_family(
+        let now = Instant::now();
+        let now_epoch_secs = MePool::now_epoch_secs();
+        let v4_degraded_raw = check_family(
             IpFamily::V4,
             &pool,
             &rng,
@@ -106,25 +155,53 @@ pub async fn me_health_monitor(pool: Arc<MePool>, rng: Arc<SecureRandom>, _min_c
             &mut drain_soft_evict_next_allowed,
         )
         .await;
-        let v6_degraded = check_family(
-            IpFamily::V6,
+        let v4_degraded = apply_family_circuit_result(
             &pool,
-            &rng,
-            &mut backoff,
-            &mut next_attempt,
-            &mut inflight,
-            &mut outage_backoff,
-            &mut outage_next_attempt,
-            &mut single_endpoint_outage,
-            &mut shadow_rotate_deadline,
-            &mut idle_refresh_next_attempt,
-            &mut adaptive_idle_since,
-            &mut adaptive_recover_until,
-            &mut floor_warn_next_allowed,
-            &mut drain_warn_next_allowed,
-            &mut drain_soft_evict_next_allowed,
-        )
-        .await;
+            IpFamily::V4,
+            &mut family_v4_circuit,
+            Some(v4_degraded_raw),
+            false,
+            now,
+            now_epoch_secs,
+        );
+
+        let v6_check_ran = should_run_family_check(&mut family_v6_circuit, now);
+        let v6_degraded_raw = if v6_check_ran {
+            check_family(
+                IpFamily::V6,
+                &pool,
+                &rng,
+                &mut backoff,
+                &mut next_attempt,
+                &mut inflight,
+                &mut outage_backoff,
+                &mut outage_next_attempt,
+                &mut single_endpoint_outage,
+                &mut shadow_rotate_deadline,
+                &mut idle_refresh_next_attempt,
+                &mut adaptive_idle_since,
+                &mut adaptive_recover_until,
+                &mut floor_warn_next_allowed,
+                &mut drain_warn_next_allowed,
+                &mut drain_soft_evict_next_allowed,
+            )
+            .await
+        } else {
+            false
+        };
+        let v6_degraded = apply_family_circuit_result(
+            &pool,
+            IpFamily::V6,
+            &mut family_v6_circuit,
+            if v6_check_ran {
+                Some(v6_degraded_raw)
+            } else {
+                None
+            },
+            true,
+            now,
+            now_epoch_secs,
+        );
         degraded_interval = v4_degraded || v6_degraded;
     }
 }
@@ -146,6 +223,148 @@ pub async fn me_drain_timeout_enforcer(pool: Arc<MePool>) {
     }
 }
 
+fn should_run_family_check(circuit: &mut FamilyCircuitState, now: Instant) -> bool {
+    match circuit.state {
+        MeFamilyRuntimeState::Suppressed => {
+            if now < circuit.next_probe_at {
+                return false;
+            }
+            circuit.next_probe_at =
+                now + Duration::from_secs(FAMILY_RECOVER_PROBE_INTERVAL_SECS);
+            true
+        }
+        _ => true,
+    }
+}
+
+fn apply_family_circuit_result(
+    pool: &Arc<MePool>,
+    family: IpFamily,
+    circuit: &mut FamilyCircuitState,
+    degraded: Option<bool>,
+    allow_suppress: bool,
+    now: Instant,
+    now_epoch_secs: u64,
+) -> bool {
+    let Some(degraded) = degraded else {
+        // Preserve suppression state when probe tick is intentionally skipped.
+        return false;
+    };
+
+    let previous_state = circuit.state;
+    match circuit.state {
+        MeFamilyRuntimeState::Suppressed => {
+            if degraded {
+                circuit.fail_streak = circuit.fail_streak.saturating_add(1);
+                circuit.recover_success_streak = 0;
+                let until = now + Duration::from_secs(FAMILY_SUPPRESS_WINDOW_SECS);
+                circuit.suppressed_until = Some(until);
+                circuit.state_since_at = now;
+                warn!(
+                    ?family,
+                    fail_streak = circuit.fail_streak,
+                    suppress_secs = FAMILY_SUPPRESS_WINDOW_SECS,
+                    "ME family remains suppressed due to ongoing failures"
+                );
+            } else {
+                circuit.fail_streak = 0;
+                circuit.recover_success_streak = 1;
+                circuit.state = MeFamilyRuntimeState::Recovering;
+            }
+        }
+        MeFamilyRuntimeState::Recovering => {
+            if degraded {
+                circuit.fail_streak = circuit.fail_streak.saturating_add(1);
+                if allow_suppress {
+                    circuit.state = MeFamilyRuntimeState::Suppressed;
+                    let until = now + Duration::from_secs(FAMILY_SUPPRESS_WINDOW_SECS);
+                    circuit.suppressed_until = Some(until);
+                    circuit.next_probe_at =
+                        now + Duration::from_secs(FAMILY_RECOVER_PROBE_INTERVAL_SECS);
+                    warn!(
+                        ?family,
+                        fail_streak = circuit.fail_streak,
+                        suppress_secs = FAMILY_SUPPRESS_WINDOW_SECS,
+                        "ME family temporarily suppressed after repeated degradation"
+                    );
+                } else {
+                    circuit.state = MeFamilyRuntimeState::Degraded;
+                }
+            } else {
+                circuit.recover_success_streak = circuit.recover_success_streak.saturating_add(1);
+                if circuit.recover_success_streak >= FAMILY_RECOVER_SUCCESS_STREAK_REQUIRED {
+                    circuit.fail_streak = 0;
+                    circuit.recover_success_streak = 0;
+                    circuit.suppressed_until = None;
+                    circuit.state = MeFamilyRuntimeState::Healthy;
+                    info!(
+                        ?family,
+                        "ME family suppression lifted after stable recovery probes"
+                    );
+                }
+            }
+        }
+        _ => {
+            if degraded {
+                circuit.fail_streak = circuit.fail_streak.saturating_add(1);
+                circuit.recover_success_streak = 0;
+                circuit.state = MeFamilyRuntimeState::Degraded;
+                if allow_suppress && circuit.fail_streak >= FAMILY_SUPPRESS_FAIL_STREAK_THRESHOLD {
+                    circuit.state = MeFamilyRuntimeState::Suppressed;
+                    let until = now + Duration::from_secs(FAMILY_SUPPRESS_WINDOW_SECS);
+                    circuit.suppressed_until = Some(until);
+                    circuit.next_probe_at =
+                        now + Duration::from_secs(FAMILY_RECOVER_PROBE_INTERVAL_SECS);
+                    warn!(
+                        ?family,
+                        fail_streak = circuit.fail_streak,
+                        suppress_secs = FAMILY_SUPPRESS_WINDOW_SECS,
+                        "ME family temporarily suppressed after repeated degradation"
+                    );
+                }
+            } else {
+                circuit.fail_streak = 0;
+                circuit.recover_success_streak = 0;
+                circuit.suppressed_until = None;
+                circuit.state = MeFamilyRuntimeState::Healthy;
+            }
+        }
+    }
+
+    if previous_state != circuit.state {
+        circuit.state_since_at = now;
+    }
+
+    let suppressed_until_epoch_secs = circuit
+        .suppressed_until
+        .and_then(|until| {
+            if until > now {
+                Some(
+                    now_epoch_secs
+                        .saturating_add(until.saturating_duration_since(now).as_secs()),
+                )
+            } else {
+                None
+            }
+        })
+        .unwrap_or(0);
+    let state_since_epoch_secs = if previous_state == circuit.state {
+        pool.family_runtime_state_since_epoch_secs(family)
+    } else {
+        now_epoch_secs
+    };
+    pool.set_family_runtime_state(
+        family,
+        circuit.state,
+        state_since_epoch_secs,
+        suppressed_until_epoch_secs,
+        circuit.fail_streak,
+        circuit.recover_success_streak,
+    );
+
+    !matches!(circuit.state, MeFamilyRuntimeState::Suppressed) && degraded
+}
+
 fn draining_writer_timeout_expired(
     pool: &MePool,
     writer: &MeWriter,
@@ -358,7 +577,8 @@ pub(super) async fn reap_draining_writers(
             continue;
         }
         pool.stats.increment_pool_force_close_total();
-        pool.remove_writer_and_close_clients(writer_id).await;
+        pool.remove_writer_and_close_clients(writer_id, MeWriterTeardownReason::ReapTimeoutExpired)
+            .await;
         pool.stats
             .increment_me_draining_writers_reap_progress_total();
     }
@@ -376,7 +596,8 @@ pub(super) async fn reap_draining_writers(
             continue;
         }
         pool.stats.increment_pool_force_close_total();
-        pool.remove_writer_and_close_clients(writer_id).await;
+        pool.remove_writer_and_close_clients(writer_id, MeWriterTeardownReason::ReapThresholdForce)
+            .await;
         pool.stats
             .increment_me_draining_writers_reap_progress_total();
         closed_total = closed_total.saturating_add(1);
@@ -388,7 +609,8 @@ pub(super) async fn reap_draining_writers(
         if !closed_writer_ids.insert(writer_id) {
             continue;
         }
-        pool.remove_writer_and_close_clients(writer_id).await;
+        pool.remove_writer_and_close_clients(writer_id, MeWriterTeardownReason::ReapEmpty)
+            .await;
         pool.stats
             .increment_me_draining_writers_reap_progress_total();
         closed_total = closed_total.saturating_add(1);
@@ -1646,11 +1868,14 @@ pub async fn me_zombie_writer_watchdog(pool: Arc<MePool>) {
         for (writer_id, had_clients) in &zombie_ids_with_meta {
             let result = tokio::time::timeout(
                 Duration::from_secs(REMOVE_TIMEOUT_SECS),
-                pool.remove_writer_and_close_clients(*writer_id),
+                pool.remove_writer_and_close_clients(
+                    *writer_id,
+                    MeWriterTeardownReason::WatchdogStuckDraining,
+                ),
             )
             .await;
             match result {
-                Ok(()) => {
+                Ok(true) => {
                     removal_timeout_streak.remove(writer_id);
                     pool.stats.increment_pool_force_close_total();
                     pool.stats
@@ -1661,7 +1886,16 @@ pub async fn me_zombie_writer_watchdog(pool: Arc<MePool>) {
                         "Zombie writer removed by watchdog"
                     );
                 }
+                Ok(false) => {
+                    removal_timeout_streak.remove(writer_id);
+                    debug!(
+                        writer_id,
+                        had_clients,
+                        "Zombie writer watchdog removal became no-op"
+                    );
+                }
                 Err(_) => {
+                    pool.stats.increment_me_writer_teardown_timeout_total();
                     let streak = removal_timeout_streak
                         .entry(*writer_id)
                         .and_modify(|value| *value = value.saturating_add(1))
@@ -1675,10 +1909,14 @@ pub async fn me_zombie_writer_watchdog(pool: Arc<MePool>) {
                     if *streak < HARD_DETACH_TIMEOUT_STREAK {
                         continue;
                     }
+                    pool.stats.increment_me_writer_teardown_escalation_total();
 
                     let hard_detach = tokio::time::timeout(
                         Duration::from_secs(REMOVE_TIMEOUT_SECS),
-                        pool.remove_draining_writer_hard_detach(*writer_id),
+                        pool.remove_draining_writer_hard_detach(
+                            *writer_id,
+                            MeWriterTeardownReason::WatchdogStuckDraining,
+                        ),
                     )
                     .await;
                     match hard_detach {
@@ -1702,6 +1940,7 @@ pub async fn me_zombie_writer_watchdog(pool: Arc<MePool>) {
                             );
                         }
                         Err(_) => {
+                            pool.stats.increment_me_writer_teardown_timeout_total();
                             warn!(
                                 writer_id,
                                 had_clients,
@@ -1725,13 +1964,19 @@ mod tests {
     use tokio::sync::mpsc;
     use tokio_util::sync::CancellationToken;
 
-    use super::reap_draining_writers;
+    use super::{
+        FamilyCircuitState, apply_family_circuit_result, reap_draining_writers,
+        should_run_family_check,
+    };
     use crate::config::{GeneralConfig, MeRouteNoWriterMode, MeSocksKdfPolicy, MeWriterPickMode};
     use crate::crypto::SecureRandom;
+    use crate::network::IpFamily;
     use crate::network::probe::NetworkDecision;
     use crate::stats::Stats;
     use crate::transport::middle_proxy::codec::WriterCommand;
-    use crate::transport::middle_proxy::pool::{MePool, MeWriter, WriterContour};
+    use crate::transport::middle_proxy::pool::{
+        MeFamilyRuntimeState, MePool, MeWriter, WriterContour,
+    };
     use crate::transport::middle_proxy::registry::ConnMeta;
 
     async fn make_pool(me_pool_drain_threshold: u64) -> Arc<MePool> {
@@ -1909,4 +2154,47 @@ mod tests {
         assert_eq!(pool.registry.get_writer(conn_b).await.unwrap().writer_id, 20);
         assert_eq!(pool.registry.get_writer(conn_c).await.unwrap().writer_id, 30);
     }
+
+    #[tokio::test]
+    async fn suppressed_family_probe_skip_preserves_suppressed_state() {
+        let pool = make_pool(0).await;
+        let now = Instant::now();
+        let now_epoch_secs = MePool::now_epoch_secs();
+        let suppressed_until_epoch_secs = now_epoch_secs.saturating_add(60);
+        pool.set_family_runtime_state(
+            IpFamily::V6,
+            MeFamilyRuntimeState::Suppressed,
+            now_epoch_secs,
+            suppressed_until_epoch_secs,
+            7,
+            0,
+        );
+
+        let mut circuit = FamilyCircuitState {
+            state: MeFamilyRuntimeState::Suppressed,
+            state_since_at: now,
+            suppressed_until: Some(now + Duration::from_secs(60)),
+            next_probe_at: now + Duration::from_secs(5),
+            fail_streak: 7,
+            recover_success_streak: 0,
+        };
+
+        assert!(!should_run_family_check(&mut circuit, now));
+        assert!(!apply_family_circuit_result(
+            &pool,
+            IpFamily::V6,
+            &mut circuit,
+            None,
+            true,
+            now,
+            now_epoch_secs,
+        ));
+        assert_eq!(circuit.state, MeFamilyRuntimeState::Suppressed);
+        assert_eq!(circuit.fail_streak, 7);
+        assert_eq!(circuit.recover_success_streak, 0);
+        assert_eq!(
+            pool.family_runtime_state(IpFamily::V6),
+            MeFamilyRuntimeState::Suppressed,
+        );
+    }
 }

src/transport/middle_proxy/health_adversarial_tests.rs

@@ -316,7 +316,12 @@ async fn reap_draining_writers_maintains_warn_state_subset_property_under_bulk_c
 
         let ids = sorted_writer_ids(&pool).await;
         for writer_id in ids.into_iter().take(3) {
-            let _ = pool.remove_writer_and_close_clients(writer_id).await;
+            let _ = pool
+                .remove_writer_and_close_clients(
+                    writer_id,
+                    crate::stats::MeWriterTeardownReason::ReapEmpty,
+                )
+                .await;
         }
 
         reap_draining_writers(&pool, &mut warn_next_allowed, &mut soft_evict_next_allowed).await;

src/transport/middle_proxy/health_regression_tests.rs

@@ -197,7 +197,9 @@ async fn reap_draining_writers_drops_warn_state_for_removed_writer() {
     reap_draining_writers(&pool, &mut warn_next_allowed, &mut soft_evict_next_allowed).await;
     assert!(warn_next_allowed.contains_key(&7));
 
-    let _ = pool.remove_writer_and_close_clients(7).await;
+    let _ = pool
+        .remove_writer_and_close_clients(7, crate::stats::MeWriterTeardownReason::ReapEmpty)
+        .await;
     assert!(pool.registry.get_writer(conn_ids[0]).await.is_none());
 
     reap_draining_writers(&pool, &mut warn_next_allowed, &mut soft_evict_next_allowed).await;
@@ -527,7 +529,12 @@ async fn reap_draining_writers_warn_state_never_exceeds_live_draining_population
 
         let existing_writer_ids = current_writer_ids(&pool).await;
         for writer_id in existing_writer_ids.into_iter().take(4) {
-            let _ = pool.remove_writer_and_close_clients(writer_id).await;
+            let _ = pool
+                .remove_writer_and_close_clients(
+                    writer_id,
+                    crate::stats::MeWriterTeardownReason::ReapEmpty,
+                )
+                .await;
         }
         reap_draining_writers(&pool, &mut warn_next_allowed, &mut soft_evict_next_allowed).await;
         assert!(warn_next_allowed.len() <= pool.writers.read().await.len());

src/transport/middle_proxy/pool.rs

@@ -74,6 +74,64 @@ impl WriterContour {
     }
 }
 
+#[derive(Debug, Clone, Copy, PartialEq, Eq)]
+#[repr(u8)]
+pub(crate) enum MeFamilyRuntimeState {
+    Healthy = 0,
+    Degraded = 1,
+    Suppressed = 2,
+    Recovering = 3,
+}
+
+impl MeFamilyRuntimeState {
+    pub(crate) fn from_u8(value: u8) -> Self {
+        match value {
+            1 => Self::Degraded,
+            2 => Self::Suppressed,
+            3 => Self::Recovering,
+            _ => Self::Healthy,
+        }
+    }
+
+    pub(crate) fn as_str(self) -> &'static str {
+        match self {
+            Self::Healthy => "healthy",
+            Self::Degraded => "degraded",
+            Self::Suppressed => "suppressed",
+            Self::Recovering => "recovering",
+        }
+    }
+}
+
+#[derive(Debug, Clone, Copy, PartialEq, Eq)]
+#[repr(u8)]
+pub(crate) enum MeDrainGateReason {
+    Open = 0,
+    CoverageQuorum = 1,
+    Redundancy = 2,
+    SuppressionActive = 3,
+}
+
+impl MeDrainGateReason {
+    pub(crate) fn from_u8(value: u8) -> Self {
+        match value {
+            1 => Self::CoverageQuorum,
+            2 => Self::Redundancy,
+            3 => Self::SuppressionActive,
+            _ => Self::Open,
+        }
+    }
+
+    pub(crate) fn as_str(self) -> &'static str {
+        match self {
+            Self::Open => "open",
+            Self::CoverageQuorum => "coverage_quorum",
+            Self::Redundancy => "redundancy",
+            Self::SuppressionActive => "suppression_active",
+        }
+    }
+}
+
 #[derive(Debug, Clone)]
 pub struct SecretSnapshot {
     pub epoch: u64,
@@ -203,6 +261,20 @@ pub struct MePool {
     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) me_family_v4_runtime_state: AtomicU8,
+    pub(super) me_family_v6_runtime_state: AtomicU8,
+    pub(super) me_family_v4_state_since_epoch_secs: AtomicU64,
+    pub(super) me_family_v6_state_since_epoch_secs: AtomicU64,
+    pub(super) me_family_v4_suppressed_until_epoch_secs: AtomicU64,
+    pub(super) me_family_v6_suppressed_until_epoch_secs: AtomicU64,
+    pub(super) me_family_v4_fail_streak: AtomicU32,
+    pub(super) me_family_v6_fail_streak: AtomicU32,
+    pub(super) me_family_v4_recover_success_streak: AtomicU32,
+    pub(super) me_family_v6_recover_success_streak: AtomicU32,
+    pub(super) me_last_drain_gate_route_quorum_ok: AtomicBool,
+    pub(super) me_last_drain_gate_redundancy_ok: AtomicBool,
+    pub(super) me_last_drain_gate_block_reason: AtomicU8,
+    pub(super) me_last_drain_gate_updated_at_epoch_secs: AtomicU64,
     pub(super) runtime_ready: AtomicBool,
     pool_size: usize,
     pub(super) preferred_endpoints_by_dc: Arc<RwLock<HashMap<i32, Vec<SocketAddr>>>>,
@@ -518,6 +590,20 @@ impl MePool {
             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)),
+            me_family_v4_runtime_state: AtomicU8::new(MeFamilyRuntimeState::Healthy as u8),
+            me_family_v6_runtime_state: AtomicU8::new(MeFamilyRuntimeState::Healthy as u8),
+            me_family_v4_state_since_epoch_secs: AtomicU64::new(Self::now_epoch_secs()),
+            me_family_v6_state_since_epoch_secs: AtomicU64::new(Self::now_epoch_secs()),
+            me_family_v4_suppressed_until_epoch_secs: AtomicU64::new(0),
+            me_family_v6_suppressed_until_epoch_secs: AtomicU64::new(0),
+            me_family_v4_fail_streak: AtomicU32::new(0),
+            me_family_v6_fail_streak: AtomicU32::new(0),
+            me_family_v4_recover_success_streak: AtomicU32::new(0),
+            me_family_v6_recover_success_streak: AtomicU32::new(0),
+            me_last_drain_gate_route_quorum_ok: AtomicBool::new(false),
+            me_last_drain_gate_redundancy_ok: AtomicBool::new(false),
+            me_last_drain_gate_block_reason: AtomicU8::new(MeDrainGateReason::Open as u8),
+            me_last_drain_gate_updated_at_epoch_secs: AtomicU64::new(Self::now_epoch_secs()),
             runtime_ready: AtomicBool::new(false),
             preferred_endpoints_by_dc: Arc::new(RwLock::new(preferred_endpoints_by_dc)),
         })
@@ -535,6 +621,153 @@ impl MePool {
         self.runtime_ready.load(Ordering::Relaxed)
     }
 
+    pub(super) fn set_family_runtime_state(
+        &self,
+        family: IpFamily,
+        state: MeFamilyRuntimeState,
+        state_since_epoch_secs: u64,
+        suppressed_until_epoch_secs: u64,
+        fail_streak: u32,
+        recover_success_streak: u32,
+    ) {
+        match family {
+            IpFamily::V4 => {
+                self.me_family_v4_runtime_state
+                    .store(state as u8, Ordering::Relaxed);
+                self.me_family_v4_state_since_epoch_secs
+                    .store(state_since_epoch_secs, Ordering::Relaxed);
+                self.me_family_v4_suppressed_until_epoch_secs
+                    .store(suppressed_until_epoch_secs, Ordering::Relaxed);
+                self.me_family_v4_fail_streak
+                    .store(fail_streak, Ordering::Relaxed);
+                self.me_family_v4_recover_success_streak
+                    .store(recover_success_streak, Ordering::Relaxed);
+            }
+            IpFamily::V6 => {
+                self.me_family_v6_runtime_state
+                    .store(state as u8, Ordering::Relaxed);
+                self.me_family_v6_state_since_epoch_secs
+                    .store(state_since_epoch_secs, Ordering::Relaxed);
+                self.me_family_v6_suppressed_until_epoch_secs
+                    .store(suppressed_until_epoch_secs, Ordering::Relaxed);
+                self.me_family_v6_fail_streak
+                    .store(fail_streak, Ordering::Relaxed);
+                self.me_family_v6_recover_success_streak
+                    .store(recover_success_streak, Ordering::Relaxed);
+            }
+        }
+    }
+
+    pub(crate) fn family_runtime_state(&self, family: IpFamily) -> MeFamilyRuntimeState {
+        match family {
+            IpFamily::V4 => MeFamilyRuntimeState::from_u8(
+                self.me_family_v4_runtime_state.load(Ordering::Relaxed),
+            ),
+            IpFamily::V6 => MeFamilyRuntimeState::from_u8(
+                self.me_family_v6_runtime_state.load(Ordering::Relaxed),
+            ),
+        }
+    }
+
+    pub(crate) fn family_runtime_state_since_epoch_secs(&self, family: IpFamily) -> u64 {
+        match family {
+            IpFamily::V4 => self
+                .me_family_v4_state_since_epoch_secs
+                .load(Ordering::Relaxed),
+            IpFamily::V6 => self
+                .me_family_v6_state_since_epoch_secs
+                .load(Ordering::Relaxed),
+        }
+    }
+
+    pub(crate) fn family_suppressed_until_epoch_secs(&self, family: IpFamily) -> u64 {
+        match family {
+            IpFamily::V4 => self
+                .me_family_v4_suppressed_until_epoch_secs
+                .load(Ordering::Relaxed),
+            IpFamily::V6 => self
+                .me_family_v6_suppressed_until_epoch_secs
+                .load(Ordering::Relaxed),
+        }
+    }
+
+    pub(crate) fn family_fail_streak(&self, family: IpFamily) -> u32 {
+        match family {
+            IpFamily::V4 => self.me_family_v4_fail_streak.load(Ordering::Relaxed),
+            IpFamily::V6 => self.me_family_v6_fail_streak.load(Ordering::Relaxed),
+        }
+    }
+
+    pub(crate) fn family_recover_success_streak(&self, family: IpFamily) -> u32 {
+        match family {
+            IpFamily::V4 => self
+                .me_family_v4_recover_success_streak
+                .load(Ordering::Relaxed),
+            IpFamily::V6 => self
+                .me_family_v6_recover_success_streak
+                .load(Ordering::Relaxed),
+        }
+    }
+
+    pub(crate) fn is_family_temporarily_suppressed(
+        &self,
+        family: IpFamily,
+        now_epoch_secs: u64,
+    ) -> bool {
+        self.family_suppressed_until_epoch_secs(family) > now_epoch_secs
+    }
+
+    pub(super) fn family_enabled_for_drain_coverage(
+        &self,
+        family: IpFamily,
+        now_epoch_secs: u64,
+    ) -> bool {
+        let configured = match family {
+            IpFamily::V4 => self.decision.ipv4_me,
+            IpFamily::V6 => self.decision.ipv6_me,
+        };
+        configured && !self.is_family_temporarily_suppressed(family, now_epoch_secs)
+    }
+
+    pub(super) fn set_last_drain_gate(
+        &self,
+        route_quorum_ok: bool,
+        redundancy_ok: bool,
+        block_reason: MeDrainGateReason,
+        updated_at_epoch_secs: u64,
+    ) {
+        self.me_last_drain_gate_route_quorum_ok
+            .store(route_quorum_ok, Ordering::Relaxed);
+        self.me_last_drain_gate_redundancy_ok
+            .store(redundancy_ok, Ordering::Relaxed);
+        self.me_last_drain_gate_block_reason
+            .store(block_reason as u8, Ordering::Relaxed);
+        self.me_last_drain_gate_updated_at_epoch_secs
+            .store(updated_at_epoch_secs, Ordering::Relaxed);
+    }
+
+    pub(crate) fn last_drain_gate_route_quorum_ok(&self) -> bool {
+        self.me_last_drain_gate_route_quorum_ok
+            .load(Ordering::Relaxed)
+    }
+
+    pub(crate) fn last_drain_gate_redundancy_ok(&self) -> bool {
+        self.me_last_drain_gate_redundancy_ok
+            .load(Ordering::Relaxed)
+    }
+
+    pub(crate) fn last_drain_gate_block_reason(&self) -> MeDrainGateReason {
+        MeDrainGateReason::from_u8(
+            self.me_last_drain_gate_block_reason
+                .load(Ordering::Relaxed),
+        )
+    }
+
+    pub(crate) fn last_drain_gate_updated_at_epoch_secs(&self) -> u64 {
+        self.me_last_drain_gate_updated_at_epoch_secs
+            .load(Ordering::Relaxed)
+    }
+
     pub fn update_runtime_reinit_policy(
         &self,
         hardswap: bool,
@@ -1021,9 +1254,10 @@ impl MePool {
     }
 
     pub(super) async fn active_coverage_required_total(&self) -> usize {
+        let now_epoch_secs = Self::now_epoch_secs();
         let mut endpoints_by_dc = HashMap::<i32, HashSet<SocketAddr>>::new();
 
-        if self.decision.ipv4_me {
+        if self.family_enabled_for_drain_coverage(IpFamily::V4, now_epoch_secs) {
             let map = self.proxy_map_v4.read().await;
             for (dc, addrs) in map.iter() {
                 let entry = endpoints_by_dc.entry(*dc).or_default();
@@ -1033,7 +1267,7 @@ impl MePool {
             }
         }
 
-        if self.decision.ipv6_me {
+        if self.family_enabled_for_drain_coverage(IpFamily::V6, now_epoch_secs) {
             let map = self.proxy_map_v6.read().await;
             for (dc, addrs) in map.iter() {
                 let entry = endpoints_by_dc.entry(*dc).or_default();

src/transport/middle_proxy/pool_refill.rs

@@ -164,9 +164,10 @@ impl MePool {
     }
 
     async fn endpoints_for_dc(&self, target_dc: i32) -> Vec<SocketAddr> {
+        let now_epoch_secs = Self::now_epoch_secs();
         let mut endpoints = HashSet::<SocketAddr>::new();
 
-        if self.decision.ipv4_me {
+        if self.family_enabled_for_drain_coverage(IpFamily::V4, now_epoch_secs) {
             let map = self.proxy_map_v4.read().await;
             if let Some(addrs) = map.get(&target_dc) {
                 for (ip, port) in addrs {
@@ -175,7 +176,7 @@ impl MePool {
             }
         }
 
-        if self.decision.ipv6_me {
+        if self.family_enabled_for_drain_coverage(IpFamily::V6, now_epoch_secs) {
             let map = self.proxy_map_v6.read().await;
             if let Some(addrs) = map.get(&target_dc) {
                 for (ip, port) in addrs {

src/transport/middle_proxy/pool_reinit.rs

@@ -11,8 +11,9 @@ use tracing::{debug, info, warn};
 use std::collections::hash_map::DefaultHasher;
 
 use crate::crypto::SecureRandom;
+use crate::network::IpFamily;
 
-use super::pool::{MePool, WriterContour};
+use super::pool::{MeDrainGateReason, MePool, WriterContour};
 
 const ME_HARDSWAP_PENDING_TTL_SECS: u64 = 1800;
 
@@ -120,9 +121,10 @@ impl MePool {
     }
 
     async fn desired_dc_endpoints(&self) -> HashMap<i32, HashSet<SocketAddr>> {
+        let now_epoch_secs = Self::now_epoch_secs();
         let mut out: HashMap<i32, HashSet<SocketAddr>> = HashMap::new();
 
-        if self.decision.ipv4_me {
+        if self.family_enabled_for_drain_coverage(IpFamily::V4, now_epoch_secs) {
             let map_v4 = self.proxy_map_v4.read().await.clone();
             for (dc, addrs) in map_v4 {
                 let entry = out.entry(dc).or_default();
@@ -132,7 +134,7 @@ impl MePool {
             }
         }
 
-        if self.decision.ipv6_me {
+        if self.family_enabled_for_drain_coverage(IpFamily::V6, now_epoch_secs) {
             let map_v6 = self.proxy_map_v6.read().await.clone();
             for (dc, addrs) in map_v6 {
                 let entry = out.entry(dc).or_default();
@@ -313,13 +315,23 @@ impl MePool {
 
     pub async fn zero_downtime_reinit_after_map_change(self: &Arc<Self>, rng: &SecureRandom) {
         let desired_by_dc = self.desired_dc_endpoints().await;
+        let now_epoch_secs = Self::now_epoch_secs();
+        let v4_suppressed = self.is_family_temporarily_suppressed(IpFamily::V4, now_epoch_secs);
+        let v6_suppressed = self.is_family_temporarily_suppressed(IpFamily::V6, now_epoch_secs);
         if desired_by_dc.is_empty() {
             warn!("ME endpoint map is empty; skipping stale writer drain");
+            let reason = if (self.decision.ipv4_me && v4_suppressed)
+                || (self.decision.ipv6_me && v6_suppressed)
+            {
+                MeDrainGateReason::SuppressionActive
+            } else {
+                MeDrainGateReason::CoverageQuorum
+            };
+            self.set_last_drain_gate(false, false, reason, now_epoch_secs);
             return;
         }
 
         let desired_map_hash = Self::desired_map_hash(&desired_by_dc);
-        let now_epoch_secs = Self::now_epoch_secs();
         let previous_generation = self.current_generation();
         let hardswap = self.hardswap.load(Ordering::Relaxed);
         let generation = if hardswap {
@@ -390,7 +402,17 @@ impl MePool {
                 .load(Ordering::Relaxed),
         );
         let (coverage_ratio, missing_dc) = Self::coverage_ratio(&desired_by_dc, &active_writer_addrs);
+        let mut route_quorum_ok = coverage_ratio >= min_ratio;
+        let mut redundancy_ok = missing_dc.is_empty();
+        let mut redundancy_missing_dc = missing_dc.clone();
+        let mut gate_coverage_ratio = coverage_ratio;
         if !hardswap && coverage_ratio < min_ratio {
+            self.set_last_drain_gate(
+                false,
+                redundancy_ok,
+                MeDrainGateReason::CoverageQuorum,
+                now_epoch_secs,
+            );
             warn!(
                 previous_generation,
                 generation,
@@ -411,7 +433,17 @@ impl MePool {
                 .collect();
             let (fresh_coverage_ratio, fresh_missing_dc) =
                 Self::coverage_ratio(&desired_by_dc, &fresh_writer_addrs);
-            if !fresh_missing_dc.is_empty() {
+            route_quorum_ok = fresh_coverage_ratio >= min_ratio;
+            redundancy_ok = fresh_missing_dc.is_empty();
+            redundancy_missing_dc = fresh_missing_dc.clone();
+            gate_coverage_ratio = fresh_coverage_ratio;
+            if fresh_coverage_ratio < min_ratio {
+                self.set_last_drain_gate(
+                    false,
+                    redundancy_ok,
+                    MeDrainGateReason::CoverageQuorum,
+                    now_epoch_secs,
+                );
                 warn!(
                     previous_generation,
                     generation,
@@ -421,13 +453,16 @@ impl MePool {
                 );
                 return;
             }
-        } else if !missing_dc.is_empty() {
+        }
+
+        self.set_last_drain_gate(route_quorum_ok, redundancy_ok, MeDrainGateReason::Open, now_epoch_secs);
+        if !redundancy_ok {
             warn!(
-                missing_dc = ?missing_dc,
-                // Keep stale writers alive when fresh coverage is incomplete.
-                "ME reinit coverage incomplete; keeping stale writers"
+                missing_dc = ?redundancy_missing_dc,
+                coverage_ratio = format_args!("{gate_coverage_ratio:.3}"),
+                min_ratio = format_args!("{min_ratio:.3}"),
+                "ME reinit proceeds with weighted quorum while some DC groups remain uncovered"
             );
-            return;
         }
 
         if hardswap {

src/transport/middle_proxy/pool_runtime_api.rs

@@ -1,7 +1,7 @@
 use std::collections::HashMap;
 use std::time::Instant;
 
-use super::pool::{MePool, RefillDcKey};
+use super::pool::{MeDrainGateReason, MePool, RefillDcKey};
 use crate::network::IpFamily;
 
 #[derive(Clone, Debug)]
@@ -36,6 +36,24 @@ pub(crate) struct MeApiNatStunSnapshot {
     pub stun_backoff_remaining_ms: Option<u64>,
 }
 
+#[derive(Clone, Debug)]
+pub(crate) struct MeApiFamilyStateSnapshot {
+    pub family: &'static str,
+    pub state: &'static str,
+    pub state_since_epoch_secs: u64,
+    pub suppressed_until_epoch_secs: Option<u64>,
+    pub fail_streak: u32,
+    pub recover_success_streak: u32,
+}
+
+#[derive(Clone, Debug)]
+pub(crate) struct MeApiDrainGateSnapshot {
+    pub route_quorum_ok: bool,
+    pub redundancy_ok: bool,
+    pub block_reason: &'static str,
+    pub updated_at_epoch_secs: u64,
+}
+
 impl MePool {
     pub(crate) async fn api_refill_snapshot(&self) -> MeApiRefillSnapshot {
         let inflight_endpoints_total = self.refill_inflight.lock().await.len();
@@ -125,4 +143,35 @@ impl MePool {
             stun_backoff_remaining_ms,
         }
     }
+
+    pub(crate) fn api_family_state_snapshot(&self) -> Vec<MeApiFamilyStateSnapshot> {
+        [IpFamily::V4, IpFamily::V6]
+            .into_iter()
+            .map(|family| {
+                let state = self.family_runtime_state(family);
+                let suppressed_until = self.family_suppressed_until_epoch_secs(family);
+                MeApiFamilyStateSnapshot {
+                    family: match family {
+                        IpFamily::V4 => "v4",
+                        IpFamily::V6 => "v6",
+                    },
+                    state: state.as_str(),
+                    state_since_epoch_secs: self.family_runtime_state_since_epoch_secs(family),
+                    suppressed_until_epoch_secs: (suppressed_until != 0).then_some(suppressed_until),
+                    fail_streak: self.family_fail_streak(family),
+                    recover_success_streak: self.family_recover_success_streak(family),
+                }
+            })
+            .collect()
+    }
+
+    pub(crate) fn api_drain_gate_snapshot(&self) -> MeApiDrainGateSnapshot {
+        let reason: MeDrainGateReason = self.last_drain_gate_block_reason();
+        MeApiDrainGateSnapshot {
+            route_quorum_ok: self.last_drain_gate_route_quorum_ok(),
+            redundancy_ok: self.last_drain_gate_redundancy_ok(),
+            block_reason: reason.as_str(),
+            updated_at_epoch_secs: self.last_drain_gate_updated_at_epoch_secs(),
+        }
+    }
 }

src/transport/middle_proxy/pool_writer.rs

@@ -16,6 +16,9 @@ use crate::config::MeBindStaleMode;
 use crate::crypto::SecureRandom;
 use crate::error::{ProxyError, Result};
 use crate::protocol::constants::{RPC_CLOSE_EXT_U32, RPC_PING_U32};
+use crate::stats::{
+    MeWriterCleanupSideEffectStep, MeWriterTeardownMode, MeWriterTeardownReason,
+};
 
 use super::codec::{RpcWriter, WriterCommand};
 use super::pool::{MePool, MeWriter, WriterContour};
@@ -28,7 +31,7 @@ const ME_IDLE_KEEPALIVE_MAX_SECS: u64 = 5;
 const ME_RPC_PROXY_REQ_RESPONSE_WAIT_MS: u64 = 700;
 
 #[derive(Clone, Copy)]
-enum WriterTeardownMode {
+enum WriterRemoveGuardMode {
     Any,
     DrainingOnly,
 }
@@ -49,9 +52,16 @@ impl MePool {
 
         for writer_id in closed_writer_ids {
             if self.registry.is_writer_empty(writer_id).await {
-                let _ = self.remove_writer_only(writer_id).await;
+                let _ = self
+                    .remove_writer_only(writer_id, MeWriterTeardownReason::PruneClosedWriter)
+                    .await;
             } else {
-                let _ = self.remove_writer_and_close_clients(writer_id).await;
+                let _ = self
+                    .remove_writer_and_close_clients(
+                        writer_id,
+                        MeWriterTeardownReason::PruneClosedWriter,
+                    )
+                    .await;
             }
         }
     }
@@ -173,7 +183,11 @@ impl MePool {
                 .is_ok()
             {
                 if let Some(pool) = pool_writer_task.upgrade() {
-                    pool.remove_writer_and_close_clients(writer_id).await;
+                    pool.remove_writer_and_close_clients(
+                        writer_id,
+                        MeWriterTeardownReason::WriterTaskExit,
+                    )
+                    .await;
                 } else {
                     cancel_wr.cancel();
                 }
@@ -264,7 +278,11 @@ impl MePool {
                 .is_ok()
             {
                 if let Some(pool) = pool.upgrade() {
-                    pool.remove_writer_and_close_clients(writer_id).await;
+                    pool.remove_writer_and_close_clients(
+                        writer_id,
+                        MeWriterTeardownReason::ReaderExit,
+                    )
+                    .await;
                 } else {
                     // Fallback for shutdown races: make writer task exit quickly so stale
                     // channels are observable by periodic prune.
@@ -372,7 +390,11 @@ impl MePool {
                             .compare_exchange(false, true, Ordering::AcqRel, Ordering::Relaxed)
                             .is_ok()
                     {
-                        pool.remove_writer_and_close_clients(writer_id).await;
+                        pool.remove_writer_and_close_clients(
+                            writer_id,
+                            MeWriterTeardownReason::PingSendFail,
+                        )
+                        .await;
                     }
                     break;
                 }
@@ -465,7 +487,11 @@ impl MePool {
                         .compare_exchange(false, true, Ordering::AcqRel, Ordering::Relaxed)
                         .is_ok()
                     {
-                        pool.remove_writer_and_close_clients(writer_id).await;
+                        pool.remove_writer_and_close_clients(
+                            writer_id,
+                            MeWriterTeardownReason::SignalSendFail,
+                        )
+                        .await;
                     }
                     break;
                 }
@@ -499,7 +525,11 @@ impl MePool {
                         .compare_exchange(false, true, Ordering::AcqRel, Ordering::Relaxed)
                         .is_ok()
                     {
-                        pool.remove_writer_and_close_clients(writer_id).await;
+                        pool.remove_writer_and_close_clients(
+                            writer_id,
+                            MeWriterTeardownReason::SignalSendFail,
+                        )
+                        .await;
                     }
                     break;
                 }
@@ -512,25 +542,48 @@ impl MePool {
         Ok(())
     }
 
-    pub(crate) async fn remove_writer_and_close_clients(self: &Arc<Self>, writer_id: u64) {
+    pub(crate) async fn remove_writer_and_close_clients(
+        self: &Arc<Self>,
+        writer_id: u64,
+        reason: MeWriterTeardownReason,
+    ) -> bool {
         // Full client cleanup now happens inside `registry.writer_lost` to keep
         // writer reap/remove paths strictly non-blocking per connection.
-        let _ = self
-            .remove_writer_with_mode(writer_id, WriterTeardownMode::Any)
-            .await;
+        self.remove_writer_with_mode(
+            writer_id,
+            reason,
+            MeWriterTeardownMode::Normal,
+            WriterRemoveGuardMode::Any,
+        )
+        .await
     }
 
     pub(super) async fn remove_draining_writer_hard_detach(
         self: &Arc<Self>,
         writer_id: u64,
+        reason: MeWriterTeardownReason,
     ) -> bool {
-        self.remove_writer_with_mode(writer_id, WriterTeardownMode::DrainingOnly)
-            .await
+        self.remove_writer_with_mode(
+            writer_id,
+            reason,
+            MeWriterTeardownMode::HardDetach,
+            WriterRemoveGuardMode::DrainingOnly,
+        )
+        .await
     }
 
-    async fn remove_writer_only(self: &Arc<Self>, writer_id: u64) -> bool {
-        self.remove_writer_with_mode(writer_id, WriterTeardownMode::Any)
-            .await
+    async fn remove_writer_only(
+        self: &Arc<Self>,
+        writer_id: u64,
+        reason: MeWriterTeardownReason,
+    ) -> bool {
+        self.remove_writer_with_mode(
+            writer_id,
+            reason,
+            MeWriterTeardownMode::Normal,
+            WriterRemoveGuardMode::Any,
+        )
+        .await
     }
 
     // Authoritative teardown primitive shared by normal cleanup and watchdog path.
@@ -542,8 +595,13 @@ impl MePool {
     async fn remove_writer_with_mode(
         self: &Arc<Self>,
         writer_id: u64,
-        mode: WriterTeardownMode,
+        reason: MeWriterTeardownReason,
+        mode: MeWriterTeardownMode,
+        guard_mode: WriterRemoveGuardMode,
     ) -> bool {
+        let started_at = Instant::now();
+        self.stats
+            .increment_me_writer_teardown_attempt_total(reason, mode);
         let mut close_tx: Option<mpsc::Sender<WriterCommand>> = None;
         let mut removed_addr: Option<SocketAddr> = None;
         let mut removed_dc: Option<i32> = None;
@@ -553,9 +611,12 @@ impl MePool {
         {
             let mut ws = self.writers.write().await;
             if let Some(pos) = ws.iter().position(|w| w.id == writer_id) {
-                if matches!(mode, WriterTeardownMode::DrainingOnly)
+                if matches!(guard_mode, WriterRemoveGuardMode::DrainingOnly)
                     && !ws[pos].draining.load(Ordering::Relaxed)
                 {
+                    self.stats.increment_me_writer_teardown_noop_total();
+                    self.stats
+                        .observe_me_writer_teardown_duration(mode, started_at.elapsed());
                     return false;
                 }
                 let w = ws.remove(pos);
@@ -595,6 +656,9 @@ impl MePool {
                     self.stats.increment_me_writer_close_signal_drop_total();
                     self.stats
                         .increment_me_writer_close_signal_channel_full_total();
+                    self.stats.increment_me_writer_cleanup_side_effect_failures_total(
+                        MeWriterCleanupSideEffectStep::CloseSignalChannelFull,
+                    );
                     debug!(
                         writer_id,
                         "Skipping close signal for removed writer: command channel is full"
@@ -602,6 +666,9 @@ impl MePool {
                 }
                 Err(TrySendError::Closed(_)) => {
                     self.stats.increment_me_writer_close_signal_drop_total();
+                    self.stats.increment_me_writer_cleanup_side_effect_failures_total(
+                        MeWriterCleanupSideEffectStep::CloseSignalChannelClosed,
+                    );
                     debug!(
                         writer_id,
                         "Skipping close signal for removed writer: command channel is closed"
@@ -619,6 +686,13 @@ impl MePool {
                 self.trigger_immediate_refill_for_dc(addr, writer_dc);
             }
         }
+        if removed {
+            self.stats.increment_me_writer_teardown_success_total(mode);
+        } else {
+            self.stats.increment_me_writer_teardown_noop_total();
+        }
+        self.stats
+            .observe_me_writer_teardown_duration(mode, started_at.elapsed());
         removed
     }
 

src/transport/middle_proxy/send.rs

@@ -14,6 +14,7 @@ use crate::config::{MeRouteNoWriterMode, MeWriterPickMode};
 use crate::error::{ProxyError, Result};
 use crate::network::IpFamily;
 use crate::protocol::constants::{RPC_CLOSE_CONN_U32, RPC_CLOSE_EXT_U32};
+use crate::stats::MeWriterTeardownReason;
 
 use super::MePool;
 use super::codec::WriterCommand;
@@ -134,7 +135,11 @@ impl MePool {
                             Ok(()) => return Ok(()),
                             Err(TimedSendError::Closed(_)) => {
                                 warn!(writer_id = current.writer_id, "ME writer channel closed");
-                                self.remove_writer_and_close_clients(current.writer_id).await;
+                                self.remove_writer_and_close_clients(
+                                    current.writer_id,
+                                    MeWriterTeardownReason::RouteChannelClosed,
+                                )
+                                .await;
                                 continue;
                             }
                             Err(TimedSendError::Timeout(_)) => {
@@ -151,7 +156,11 @@ impl MePool {
                     }
                     Err(TrySendError::Closed(_)) => {
                         warn!(writer_id = current.writer_id, "ME writer channel closed");
-                        self.remove_writer_and_close_clients(current.writer_id).await;
+                        self.remove_writer_and_close_clients(
+                            current.writer_id,
+                            MeWriterTeardownReason::RouteChannelClosed,
+                        )
+                        .await;
                         continue;
                     }
                 }
@@ -458,7 +467,11 @@ impl MePool {
                     Err(TrySendError::Closed(_)) => {
                         self.stats.increment_me_writer_pick_closed_total(pick_mode);
                         warn!(writer_id = w.id, "ME writer channel closed");
-                        self.remove_writer_and_close_clients(w.id).await;
+                        self.remove_writer_and_close_clients(
+                            w.id,
+                            MeWriterTeardownReason::RouteChannelClosed,
+                        )
+                        .await;
                         continue;
                     }
                 }
@@ -503,7 +516,11 @@ impl MePool {
                 Err(TimedSendError::Closed(_)) => {
                     self.stats.increment_me_writer_pick_closed_total(pick_mode);
                     warn!(writer_id = w.id, "ME writer channel closed (blocking)");
-                    self.remove_writer_and_close_clients(w.id).await;
+                    self.remove_writer_and_close_clients(
+                        w.id,
+                        MeWriterTeardownReason::RouteChannelClosed,
+                    )
+                    .await;
                 }
                 Err(TimedSendError::Timeout(_)) => {
                     self.stats.increment_me_writer_pick_full_total(pick_mode);
@@ -654,7 +671,11 @@ impl MePool {
                 }
                 Err(TrySendError::Closed(_)) => {
                     debug!("ME close write failed");
-                    self.remove_writer_and_close_clients(w.writer_id).await;
+                    self.remove_writer_and_close_clients(
+                        w.writer_id,
+                        MeWriterTeardownReason::CloseRpcChannelClosed,
+                    )
+                    .await;
                 }
             }
         } else {