With tens of thousands of services, DNS lookups start timing out for five seconds at a stretch. Diagnose and fix Kubernetes DNS at scale.

The classic five-second stall is rarely CoreDNS being slow; it is UDP, conntrack races and ndots expansion. The diagnosis ladder and the NodeLocal DNSCache fix separate operators from readers of architecture blogs.

Grounded in researched DevOps, SRE and platform engineering interview loops, written to a senior-engineer editorial bar, and never padded to hit a word count.