Quiz 5 of 5: Networking and storage
13
A Service gets no traffic, and kubectl get endpointslices for it is empty. What is the most likely cause?
Why: A Service finds backends only through its label selector and readiness. Empty endpoints mean nothing matched or nothing is Ready. This is far more common than a network fault.
14
You applied a default-deny NetworkPolicy, but traffic between Pods is unchanged. What is the most likely reason?
Why: NetworkPolicy is an API object enforced by the CNI. A CNI without enforcement accepts the YAML and does nothing. Verify enforcement with a test connection.
15
You scale a Deployment that mounts one ReadWriteOnce PVC from 1 to 3 replicas and the new Pods stay Pending. What are the fixes?
Why: A RWO block disk attaches to one node at a time, so Pods on other nodes cannot mount it. Give each replica its own claim with a StatefulSet, or use a shared filesystem class that supports ReadWriteMany.