Create a Restrictive NetworkPolicy

Namespace secure-ns currently allows unrestricted ingress traffic.

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The task

Task

Namespace secure-ns currently allows unrestricted ingress traffic.

Requirements

Create a NetworkPolicy that denies all ingress traffic by default in namespace secure-ns
Create a NetworkPolicy that allows ingress traffic only from Pods inside namespace allowed-ns (labeled access=granted)

Use namespace selectors and pod selectors where required.

Verify that traffic from unauthorized namespaces is blocked.

Exam

CKS

Domain

Cluster Hardening

Grading

Programmatic · partial credit

Reference

Kubernetes docs ↗

What this tests

Restrict RBAC and service accounts, tighten API server flags, and keep the cluster patched. On the CKS exam, Cluster Hardening tasks are graded purely on what you build in the cluster — not multiple choice — so the only way to get faster is to do them on a real cluster against a clock.

Practice it for real

prepium.sh drops you into your own isolated Kubernetes cluster in the browser — no install, no credit card. You solve the task in a real terminal, hit validate, and a programmatic checker scores exactly what you got right and wrong (with partial credit). The canonical solution unlocks after you attempt it, so you learn the fast, exam-ready way to do it.

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