What is Kubernetes ClusterIP vs NodePort vs LoadBalancer?

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**Service Types** — different ways to expose Kubernetes services. ```yaml # ClusterIP (internal only) apiVersion: v1 kind: Service metadata: name: api-cluster spec: type: ClusterIP selector: app: api ports: - port: 80 targetPort: 3000 --- # NodePort (accessible via node IP:port) apiVersion: v1 kind: Service metadata: name: api-nodeport spec: type: NodePort selector: app: api ports: - port: 80 targetPort: 3000 nodePort: 30080 # 30000-32767 --- # LoadBalancer (cloud external LB) apiVersion: v1 kind: Service metadata: name: api-lb spec: type: LoadBalancer selector: app: api ports: - port: 80 targetPort: 3000 --- # ExternalName (DNS CNAME) apiVersion: v1 kind: Service metadata: name: external-db spec: type: ExternalName externalName: db.example.com ``` ```bash # Access services # ClusterIP: kubectl port-forward svc/api-cluster 8080:80 # NodePort: curl http://:30080 # LoadBalancer: curl http:// kubectl get svc -A kubectl describe svc api-cluster kubectl get endpoints api-cluster # Port forwarding kubectl port-forward svc/api-cluster 8080:80 kubectl port-forward pod/my-pod 8080:3000 ``` **Comparison:** - ClusterIP: internal, cluster IP only. - NodePort: node IP + static port (30000-32767). - LoadBalancer: external cloud LB. - ExternalName: DNS alias to external service.

DevOps: What is Kubernetes ClusterIP vs NodePort vs LoadBalancer?