Architecture Template: CoreDNS Debug ConfigMap

A production-ready CoreDNS configuration with logging, caching, and health checks for debugging DNS issues.

When to use this template:

• Setting up CoreDNS for a new cluster

• Debugging intermittent DNS failures

• Enabling DNS query logging temporarily

• Optimizing DNS performance with caching

---

Template 1: Production CoreDNS ConfigMap

This replaces the default CoreDNS Corefile with production-ready settings.

apiVersion: v1
kind: ConfigMap
metadata:
  name: coredns
  namespace: kube-system
data:
  Corefile: |
    .:53 {
        errors
        health {
            lameduck 5s
        }
        ready
        kubernetes cluster.local in-addr.arpa ip6.arpa {
            pods insecure
            fallthrough in-addr.arpa ip6.arpa
            ttl 30
        }
        prometheus :9153
        forward . /etc/resolv.conf {
            max_concurrent 1000
        }
        cache 30 {
            success 9984 30
            denial 9984 5
        }
        loop
        reload
        loadbalance
    }