Kubernetes DNS: The ndots:5 Latency Tax
Every DNS query in K8s makes 5 failed lookups before succeeding. ndots:5 default causes 100ms+ latency. Here's how to fix it properly.
#dns
5 posts
Kubernetes conntrack Table Exhaustion: The Silent Packet Killer
Random DNS timeouts, dropped connections, services timing out. Your nf_conntrack table is full. I show how to diagnose, monitor, and fix this Kubernetes networking issue.
CoreDNS vs NodeLocal DNS Cache: Cutting Kubernetes DNS Latency by 10x
Your pods make 100 DNS queries per request. CoreDNS is a bottleneck. I benchmark NodeLocal DNS cache and show configuration for production.
Go cgo DNS Resolution Thread Explosion: When net.LookupHost Spawns Thousands of Threads
Go application suddenly has 10,000 threads consuming all memory. The cause: cgo-based DNS resolution blocking in slow DNS environments, bypassing Go's goroutine scheduler.
Kubernetes Headless Service DNS: Stale Records After Pod Deletion
Requests go to non-existent pods. The cause: headless service DNS records persist in client DNS cache after pods are deleted, before endpoints update propagates.