CKA Practice Test 48 — 15 Questions

Question 1

A pod is stuck in 'Pending' state. 'kubectl describe pod' shows the following event: '0/4 nodes are available: 1 node(s) had taint {node-role.kubernetes.io/master: }, that the pod didn't tolerate, 3 node(s) had taint {node.kubernetes.io/disk-pressure: }, that the pod didn't tolerate.' Which action would resolve the issue?

Accepted Answer

Add tolerations to the pod spec matching the taints on the nodes. Option D is correct. The pod is not tolerating the taints on any node. To schedule the pod, you must add the corresponding tolerations to the pod spec. Option A would remove all pods from the node, not solve the taint issue. Option B tolerates only one taint. Option C describes the node, but does not change the pod's tolerations.

Answer

Run 'kubectl describe node node-name' on each node to check conditions

Answer

Run 'kubectl taint nodes node-name node-role.kubernetes.io/master:NoSchedule-' to remove the taint

Answer

Run 'kubectl cordon node-name' on the node with the master taint

Question 2

You are troubleshooting a scenario where a pod cannot communicate with another pod in the same namespace via service name. Which THREE steps would you take to diagnose the issue? (Select 3)

Accepted Answer

Run 'kubectl get endpoints' to verify the service has healthy endpoints. Options A, B, and C are correct. Testing DNS resolution with nslookup, checking connectivity with curl, and examining the service's endpoints are standard troubleshooting steps. Option D checks node status, which is less direct. Option E checks pod logs, which may not reveal network issues.

Answer

Run 'kubectl get nodes' to check node status

Answer

Run 'kubectl logs' on the target pod to check application logs

Question 3

Which command lists all events in the cluster sorted by timestamp?

Accepted Answer

kubectl get events --sort-by=.metadata.creationTimestamp. 'kubectl get events --sort-by=.metadata.creationTimestamp' shows events sorted by creation time. Alternatively, 'kubectl get events -w' watches events but does not sort.

Answer

kubectl get events --watch

Answer

kubectl logs --events

Answer

kubectl describe events

Question 4

A pod is in CrashLoopBackOff. You run 'kubectl logs pod-name' and see nothing. You suspect the app is failing due to a missing environment variable. Which command can you use to verify environment variables inside the container?

Accepted Answer

kubectl exec pod-name -- env. kubectl exec allows running commands inside a container. 'env' will list environment variables.

Answer

kubectl get pod pod-name -o yaml

Answer

kubectl logs pod-name --previous

Answer

kubectl describe pod pod-name

Question 5

A Pod is stuck in 'Pending' state. Upon inspection, you find that the PVC it references is also 'Pending'. Which of the following is NOT a common cause for a PVC to remain in Pending state?

Accepted Answer

The pod that references the PVC has a missing volume mount. Option D is correct. A pod using the PVC does not affect the PVC's binding process. The PVC is bound before the pod uses it. Common causes are A (no storage class), B (no provisioner), and C (quota exceeded).

Answer

The persistent volume claim requests more storage than the available persistent volumes

Answer

The storage class does not exist

Answer

The cluster does not have a default storage class

Question 6

A pod remains in Pending state. 'kubectl describe pod' shows '0/1 nodes are available: 1 node(s) had taint {node-role.kubernetes.io/master: }, that the pod didn't tolerate'. What is the solution?

Accepted Answer

Add a toleration to the pod spec. The pod cannot tolerate the master taint. Remove the taint or add tolerations.

Answer

Increase the pod's CPU request

Answer

Remove the pod and recreate it

Answer

Delete the taint from the node

Question 7

A pod is in Pending state. Which TWO are possible causes? (Select 2)

Accepted Answer

A PersistentVolumeClaim used by the pod is not bound. Pending means pod cannot be scheduled. Resource constraints and PVC not bound are common causes.

Answer

The pod's liveness probe is failing

Answer

The container image is invalid

Answer

The pod's readiness probe is failing

Question 8

You deploy a pod with a readiness probe that checks an HTTP endpoint. The probe fails and the pod is marked as 'NotReady'. Which command would you use to see the exact HTTP response from the probe?

Accepted Answer

kubectl describe pod mypod. 'kubectl describe pod' shows the probe details including the specific failure message (e.g., HTTP response code).

Answer

kubectl logs mypod -c mycontainer

Answer

kubectl exec mypod -- curl http://localhost:8080/healthz

Answer

kubectl get pod mypod -o yaml

Question 9

A pod is in CrashLoopBackOff. The YAML for the initContainer is:

apiVersion: v1
kind: Pod
metadata:
  name: myapp
spec:
  initContainers:
  - name: init
    image: busybox
    command: ['sh', '-c', 'sleep 5 && exit 1']
  containers:
  - name: app
    image: nginx

What is the most likely reason for the CrashLoopBackOff?

Accepted Answer

The init container exits with non-zero exit code. Init containers must complete successfully (exit 0) before the main container starts. An exit code 1 causes the pod to fail and restart.

Answer

The main container image nginx is not pulled successfully

Answer

The init container command is misspelled

Answer

The pod has insufficient memory

Question 10

Which command shows all recent events in the cluster, sorted by timestamp?

Accepted Answer

kubectl get events --sort-by='.lastTimestamp'. kubectl get events shows cluster events with timestamps.

Answer

kubectl describe events

Answer

kubectl get pods --show-events

Answer

kubectl logs --tail=100

Question 11

You run 'kubectl top nodes' and get an error: 'error: metrics not available yet'. Which of the following is the MOST likely cause?

Accepted Answer

The Metrics Server is not deployed in the cluster. Option D is correct. The 'metrics not available yet' error indicates that the Metrics Server is not installed or not functioning. Option A (node not ready) would show a different error. Option B (kubelet not running) would cause node NotReady. Option C (API server down) would cause connection refused.

Answer

The Kubernetes API server is down

Answer

The kubelet is not running on all nodes

Answer

One or more nodes are in NotReady state

Question 12

You suspect the kubelet on a worker node has stopped. Which two commands should you run to confirm the kubelet status and check its logs?

Accepted Answer

systemctl status kubelet and journalctl -u kubelet. To check if the kubelet is running, use 'systemctl status kubelet'. To view logs, use 'journalctl -u kubelet'. The other options target the wrong service or are not applicable.

Answer

systemctl status docker and tail -f /var/log/syslog

Answer

kubectl get nodes and kubectl describe node <node>

Answer

systemctl restart kubelet and journalctl -u containerd

Question 13

You want to see the last 50 lines of logs from a pod named 'api-pod' for the container 'api-container'. Which command accomplishes this?

Accepted Answer

kubectl logs api-pod -c api-container --tail=50. 'kubectl logs api-pod -c api-container --tail=50' shows the last 50 lines for the specified container.

Answer

kubectl logs -l app=api --tail=50

Answer

kubectl logs api-pod --tail=50

Answer

kubectl logs api-container -p api-pod --tail 50

Question 14

You cannot reach a service by its DNS name from within a pod. Running 'kubectl exec -it dnsutils -- nslookup myservice' returns 'server can't find myservice: NXDOMAIN'. Which of the following is the MOST probable cause?

Accepted Answer

The service is in a different namespace and you are not using the fully qualified name. The service exists but DNS resolution fails, often because the service is in a different namespace and the DNS query uses only the bare name.

Answer

The pod's resolv.conf is missing the cluster domain

Answer

CoreDNS is configured with a custom upstream DNS server

Answer

The kube-dns pod is not running

Question 15

A pod is stuck in 'Pending' state. Which THREE are common causes for this?

Accepted Answer

Insufficient CPU or memory resources on any node. Pending pods often indicate resource constraints (A), taint/toleration mismatch (B), or PVC not bound (C). Node not registered (D) would prevent scheduling but is less common. Image pull error (E) leads to ImagePullBackOff, not Pending.

Answer

Node not registered with the cluster

Answer

Container image name is incorrect