Kubelet Troubleshooting and Configuration

A node goes NotReady. You SSH in, run systemctl status kubelet, and see the service in a failed state. The kubelet is the only Kubernetes component that runs as a native Linux process on every node, not as a Pod. When it stops, the node stops reporting. No heartbeats, no pod status updates, no container lifecycle management. The node controller eventually taints it Unreachable and begins evicting workloads.

Fixing a broken kubelet starts with understanding how it is configured. kubeadm-provisioned clusters layer configuration across multiple files and systemd units. Knowing where each setting lives, what takes precedence, and which misconfigurations produce which symptoms turns a frustrating debug session into a methodical fix. The CKA Troubleshooting domain carries 30% of the exam weight, and kubelet failures are a staple scenario.