fix: allow DNS disconnection events to happen in k8s (#19145)

in k8s things really do come online very asynchronously,
we need to use implementation that allows this randomness.

To facilitate this move WriteAll() as part of the
websocket layer instead.

Bonus: avoid instances of dnscache usage on k8s

cmd/common-main.go

@@ -751,7 +751,12 @@ func serverHandleEnvVars() {
 		for _, endpoint := range minioEndpoints {
 			if net.ParseIP(endpoint) == nil {
 				// Checking if the IP is a DNS entry.
-				addrs, err := globalDNSCache.LookupHost(GlobalContext, endpoint)
+				lookupHost := globalDNSCache.LookupHost
+				if IsKubernetes() || IsDocker() {
+					lookupHost = net.DefaultResolver.LookupHost
+				}
+
+				addrs, err := lookupHost(GlobalContext, endpoint)
 				if err != nil {
 					logger.FatalIf(err, "Unable to initialize MinIO server with [%s] invalid entry found in MINIO_PUBLIC_IPS", endpoint)
 				}