Goal

Use a stable internal Service name for an external DNS target.

What Is Done

An ExternalName Service points to kubernetes.io. A client Pod can resolve the internal name docs-service.

Typical Commands

kubectl apply -f manifests/
kubectl get svc -n externalname-lab
kubectl exec -n externalname-lab deploy/dns-client -- nslookup docs-service

Validate Success

• The Service has type ExternalName.
• externalName points to kubernetes.io.
• The client can resolve docs-service through DNS.

Common Mistakes

• ExternalName is expected to behave like a ClusterIP Service.
• Applications expect IPs instead of CNAME resolution.
• Network or DNS policies block external resolution.