Pick and Deploy the Least Permissive NetworkPolicy
The security team left five NetworkPolicy files on the workstation. Only one of them lets the frontend reach the backend while granting nothing more. Identify it and deploy it, unchanged.
Focused, hands-on problems for sharpening your DevOps and server-side skills. Some teach specific concepts while others mirror real-world scenarios. Every challenge includes hints, feedback, and automated solution checks.
Challenges contributed by the community members sharing their knowledge and expertise.
The security team left five NetworkPolicy files on the workstation. Only one of them lets the frontend reach the backend while granting nothing more. Identify it and deploy it, unchanged.
kubectl is dead: the kube-apiserver certificate expired and the control plane is down, while the workload quietly keeps serving. Diagnose the expiry offline, renew the certificates, bring the control plane back, and prove the cluster recovered.
A Snake game Deployment and ClusterIP Service are already running in the snake namespace. Create a Traefik Ingress that serves the game over HTTPS using an existing cert-manager-issued TLS Secret.
Update a production NGINX ConfigMap to restrict TLS to v1.3 only, then verify the change enforces the security policy.
Configure the kube-scheduler static pod with CPU resource requests based on node allocatable, and disable the NodePort access to the Kubernetes API server so it is only reachable via ClusterIP.
A deployment is failing because the application cannot load its TLS certificate. Create the missing secret and mount it into the deployment so the Flask app can serve TLS traffic.
Learn how to taint a node, schedule a Pod using nodeSelector and tolerations, and share the host network, PID, and IPC namespaces with the Pod.
A multi-tier application runs across two namespaces. Learn how to isolate the application tier and restrict database access to only the application namespace.