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CKATroubleshootingTwo nodesMedium

Pods Pending on a cordoned node

Scenario cka-trb-007 · about 5 minutes · 6 points · 6 grader checks

A Deployment pinned to one node cannot schedule; find the node-level cause and fix it.

  • troubleshooting
  • scheduling
  • cordon
  • pending
  • nodeselector

What you will practise

  • Read scheduler events with kubectl describe pod
  • Recognise SchedulingDisabled on a node
  • Uncordon a node

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-007

Task

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

Deployment "pending-app" (namespace "default", 3 replicas) has pods stuck in Pending. Its pods are pinned to node "exam-w1". Find out why they cannot be scheduled and fix the cause on the node, so that all 3 replicas become Ready. Do not delete the Deployment and do not remove its nodeSelector.

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
5 minutes
Points
6
Grader checks
6
Kubernetes version
1.37
Minimum CLI version
0.1.0
Scenario version
1
Published

Grading runs locally: 6 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.