Topic 2: Services

Official baseline: (The Kubernetes Authors, 2026). My working version: A Service is a stable contract over unstable Pods: name, virtual IP, and selection rules.

Mental Model

A Service is a stable contract over unstable Pods: name, virtual IP, and selection rules.

Notes

• ClusterIP is internal service discovery.
• NodePort and LoadBalancer expose traffic through node or provider plumbing.
• Selectors decide which Pods receive traffic; labels are production routing.

Homelab Angle

Map the path from laptop to Service to Pod before adding ingress or tunnels.

Verify It

• Read the object status before changing the manifest.
• Check events for the controller or node that is actually complaining.
• Confirm the official source linked below still matches the cluster version you run.

Common Failure Modes

• Treating the YAML object as the system, instead of one input to a reconciliation loop.
• Debugging from outside the cluster when the failure only exists inside cluster networking or node state.
• Forgetting that Kubernetes version, addon version, and runtime behavior are linked.

Sources

• Service - source path: content/en/docs/concepts/services-networking/service.md, commit 8cc9e19b8eec8d5cf49eacd66f86a81648edb1a0.
• Kubernetes documentation is licensed under CC BY 4.0; these notes are original commentary and link back to the official source.

The Kubernetes Authors. (2026). Service. https://kubernetes.io/docs/concepts/services-networking/service/