Configure Istio Mutual TLS (mTLS) Authentication

Istio is installed in the cluster. Deployment target-app runs in namespace app-ns; client-pod runs in namespace client-ns.

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The task

Task

Istio is installed in the cluster. Deployment target-app runs in namespace app-ns; client-pod runs in namespace client-ns.

Requirements

Create a PeerAuthentication named target-mtls in namespace app-ns that requires STRICT mutual TLS for the target-app workload (selector app: target-app)
Add a port-level exception so port 8080 uses PERMISSIVE mode (allowing non-mTLS health/probe traffic)
Create an AuthorizationPolicy named allow-client in namespace app-ns that allows requests to target-app only from namespace client-ns

Verify that the workload requires mTLS, port 8080 is permissive, and only client-ns is authorized.

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

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