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CKATroubleshootingTwo nodesMedium

Worker NotReady: kubelet fails to start

Scenario cka-trb-002 · about 8 minutes · 7 points · 3 grader checks

The kubelet on a worker refuses to start; find the misconfiguration and fix it on the node.

  • troubleshooting
  • node
  • kubelet
  • systemd
  • configuration

What you will practise

  • Read kubelet logs with journalctl
  • Locate kubelet configuration files on a kubeadm node
  • Fix a startup error and restart the service

Start this lab

With the CLI installed and signed in, this command provisions a two nodes cluster on your Mac, applies the scenario setup and prints the task below.

goldenkube start cka-trb-002

Task

The task text exactly as the CLI shows it. Solve it on the cluster, then run goldenkube submit.

Worker node "exam-w1" is NotReady and its kubelet service is not running. Find out why the kubelet fails to start and fix it on the node. When you are done, the kubelet service on exam-w1 must be active and the node must report Ready. Do not delete or recreate the node, and do not reinstall the kubelet.

Requirements and details

Certification
CKA · Certified Kubernetes Administrator
Domain
Troubleshooting
Difficulty
Medium
Cluster topology
Two nodes
Cluster features
None beyond the base cluster
Recommended time
8 minutes
Points
7
Grader checks
3
Kubernetes version
1.37
Minimum CLI version
0.1.0
Scenario version
1
Published

Grading runs locally: 3 state checks read your cluster when you submit; the scenario passes when every check passes. Hints, the reference solution and the check definitions are available only inside the CLI, not on this page.

Install the CLICreate a free account

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Independent community project, not affiliated with or endorsed by CNCF or The Linux Foundation. Lab results are practice feedback, not an exam score.