Kubernetes Practical By Samson Tanimawo, PhD Published Feb 24, 2026 4 min read

CoreDNS Tuning at Scale

Default CoreDNS struggles at scale. The tuning.

Cache

Increase cache TTL. Reduces query load.

Trade-off: stale records.

Scale CoreDNS replicas with cluster size.

Default 2 is too few for large clusters.

ndots=2 default causes search-domain queries.

Tune lower if your apps don't use search domains.