Network Policies Interview Questions

Why Network Policies Matter in Interviews

Network Policies are a core security primitive in Kubernetes. Interviewers use them to assess whether you can move beyond basic cluster operation and implement defense-in-depth strategies that restrict pod-to-pod traffic.

Expect questions that ask you to write a default-deny policy for a namespace, allow traffic only from a specific set of Pods or namespaces, and explain what happens if the CNI plugin does not support Network Policies. You should also be ready to discuss the difference between ingress and egress rules, how to allow DNS resolution (typically port 53 to kube-dns) when egress is restricted, and how policies interact when multiple rules apply to the same Pod. Candidates who can whiteboard a policy that locks down a multi-tier application — allowing only the frontend to reach the backend, and only the backend to reach the database — demonstrate the kind of security awareness that production teams value.