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.
A new intern learning about probes wrote a small Pod manifest. The exec command and the application are both correct, but the Pod never becomes Ready because one probe parameter is missing. Find it and add it.
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.
A worker node dropped to NotReady and part of the workload went with it. The container runtime is fine and the control plane is healthy; the trail leads from kubectl symptoms down into systemd and the kubelet configuration. Diagnose the node and bring it back.
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.
Every kubectl command against a kubeadm cluster fails, and the workload is still serving. With no API to query, the usual tools tell you nothing. Work from the node itself to find what broke and bring the control plane back.
A Deployment is running in the platform namespace with 3 replicas. Each pod has configuration files at /app/config/. Copy those files to /home/laborant/config/ on the local machine.
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.
Learn how to configure a Kubernetes CronJob to automatically take etcd snapshot backups every 6 hours — a critical skill for cluster disaster recovery and operational health.
Learn how to reconfigure the Kubernetes cluster DNS domain by updating CoreDNS ConfigMap and kubelet configuration on all nodes, a critical skill for custom cluster networking and CKA exam preparation.
A Deployment running a distroless Chainguard nginx image (cgr.dev/chainguard/nginx) is deployed in the namespace webapps, fronted by a ClusterIP Service. Port-forward that Service to localhost port 3333 on cplane-01, use curl to save the response body to /home/laborant/index.html, and verify the file is accessible and contains the expected content.
