ExternalDNS

Overview

ExternalDNS synchronizes exposed Kubernetes Services, Ingresses, and Gateway API routes with DNS providers. It watches resources via the K8s watch API and creates/updates/deletes DNS records to match.

No CRDs. Controlled via CLI flags, sources, and provider-specific config.

Latest: chart 1.21.1, app v0.21.0.

Architecture

K8s Sources (Ingress, HTTPRoute, Service...)
  → ExternalDNS watches for changes
    → Resolves to DNS endpoints
      → Creates/updates/deletes DNS records (Cloudflare, Route53, etc.)
        → Registry (TXT records) tracks ownership