Challenges

Focused, hands-on DevOps and server-side problems with hints, feedback, and automated solution checks.

Challenge

CKA Practice: Recover a NotReady Node After a Kubelet Configuration Error

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.

Challenge

CKA Practice: Recover a Broken Static Control-Plane Pod

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.

Challenge

Migrate the Kubernetes Cluster DNS Domain from cluster.local to iximiuz.cluster

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.

Challenge

Troubleshoot Why the Calendar Todo App Pods Are Stuck in Pending

The production "Calendar Todo" web application has been deployed in the prod namespace but all pods are stuck in Pending. Investigate the cluster, identify why the application cannot run, fix the underlying node issue, and verify the app is serving traffic on NodePort 31777.