CKA Practice Test 44 — 15 Questions

Question 1

You have a Deployment with the following resource limits for containers: memory: 256Mi. The pod is repeatedly killed with OOMKilled. You need to change the limit to 512Mi. Which field should you modify in the Deployment YAML?

Accepted Answer

spec.template.spec.containers[].resources.limits.memory. Option C is correct. Memory limit is specified under resources.limits.memory. Option A is for requests, not limits. Option B is for CPU. Option D is for CPU.

Answer

spec.template.spec.containers[].resources.requests.memory

Answer

spec.template.spec.containers[].resources.requests.cpu

Answer

spec.template.spec.containers[].resources.limits.cpu

Question 2

A pod is in the 'Pending' state for a long time. You run 'kubectl describe pod pending-pod' and see the event: '0/4 nodes are available: 1 node(s) had taint {node.kubernetes.io/not-ready: }, 3 node(s) had taint {node-role.kubernetes.io/control-plane: } that the pod didn't tolerate.' What is the MOST likely solution?

Accepted Answer

Add tolerations to the pod for the control-plane taint. Option A is correct. The pod lacks tolerations for the control-plane taint. Adding appropriate tolerations allows scheduling on those nodes. Option B is irrelevant. Option C is not recommended. Option D does not address the root cause.

Answer

Remove the taint from the control-plane nodes

Answer

Delete the pod and recreate it

Answer

Increase the pod's resource requests

Question 3

Which TWO of the following are common causes for a pod to be in the 'Pending' state?

Accepted Answer

Insufficient cluster resources (CPU/memory) to schedule the pod. Options A and C are correct. Insufficient resources and unbound PVCs are common causes for Pending pods. Option B causes ImagePullBackOff. Option D causes CrashLoopBackOff. Option E may cause Unknown state.

Answer

The container image is not found

Answer

The pod's liveness probe is failing

Answer

The node is unreachable due to network issues

Question 4

You are troubleshooting DNS resolution from a pod. You exec into the pod and run 'nslookup kubernetes.default.svc.cluster.local'. It fails with 'server can't find kubernetes.default.svc.cluster.local: NXDOMAIN'. What is the most likely cause?

Accepted Answer

The pod's /etc/resolv.conf points to an incorrect DNS server IP. The DNS server IP might be wrong or CoreDNS might not be running. The resolver file in the pod typically points to the cluster DNS service IP.

Answer

The kubernetes service does not exist

Answer

The pod does not have network connectivity

Answer

The kube-dns service is not exposed

Question 5

You are troubleshooting a node that is in 'NotReady' state. Which command should you use to check the kubelet logs for errors?

Accepted Answer

journalctl -u kubelet. Option A is correct. The kubelet logs can be viewed using 'journalctl -u kubelet'. Option B is used for system logs, not kubelet-specific. Option C checks kube-apiserver logs. Option D checks kube-controller-manager logs.

Answer

journalctl -u docker

Answer

journalctl -u kube-apiserver

Answer

journalctl -u kube-controller-manager

Question 6

You deploy a pod with the following YAML:

apiVersion: v1
kind: Pod
metadata:
  name: test-pod
spec:
  containers:
  - name: test
    image: nginx
    resources:
      requests:
        memory: "64Mi"
        cpu: "250m"
      limits:
        memory: "128Mi"
        cpu: "500m"

The pod starts, but after a few minutes it is killed with OOMKilled. What is the MOST likely reason?

Accepted Answer

The container's memory usage exceeds the configured limit. Option D is correct. OOMKilled occurs when the container exceeds its memory limit. The limit is 128Mi, so if the nginx container uses more than 128Mi of memory, it will be killed. Option A is incorrect because CPU limits cause throttling, not OOM. Option B is incorrect because swap is typically disabled in Kubernetes. Option C is incorrect because the request is lower than the limit, which is allowed.

Answer

The memory limit is lower than the memory request

Answer

The node has swap enabled

Answer

The container is using too much CPU

Question 7

A newly created Service of type ClusterIP is not accessible from within the cluster. You exec into a pod and run 'curl http://service-name:80' but get 'Connection refused'. What is the most likely cause?

Accepted Answer

The application inside the pod is not listening on the targetPort. Connection refused indicates the application in the backend pods is not listening on the expected port, or the service's targetPort is wrong.

Answer

The service selector does not match pod labels

Answer

The backend pods are not ready

Answer

The service is not in the same namespace

Question 8

You deploy a pod with the following YAML and it remains in 'Pending' state. What is the most likely cause?

```yaml
apiVersion: v1
kind: Pod
metadata:
  name: myapp
spec:
  containers:
  - name: myapp
    image: nginx
  resources:
    requests:
      memory: "64Gi"
```

Accepted Answer

The pod requests more memory than any node can allocate.. The pod requests 64Gi of memory, which is likely not available on any node in the cluster. The pod remains Pending because no node can satisfy the resource request.

Answer

The pod is missing a required label.

Answer

The pod has a taint that no toleration matches.

Answer

The image 'nginx' does not exist.

Question 9

You try to run 'kubectl logs mypod' and get the error: 'Error from server (BadRequest): container "myapp" in pod "mypod" is waiting to start: PodInitializing'. What does this mean?

Accepted Answer

The pod is still being initialized and the container has not started yet.. The pod is still initializing (e.g., pulling images, running init containers). Logs are not available until the main container starts.

Answer

The pod has crashed and is restarting.

Answer

The kubelet is not running on the node.

Answer

The container has a different name than specified.

Question 10

Which TWO commands can be used to view logs for a pod?

Accepted Answer

kubectl describe pod my-pod. kubectl logs and kubectl describe pod (which shows events and last state) are both useful for viewing log-related information.

Answer

kubectl exec my-pod -- cat /var/log/app.log

Answer

kubectl top pod my-pod

Answer

kubectl get pod my-pod -o yaml

Question 11

You run 'kubectl get pods' and see that a pod is in 'CrashLoopBackOff'. You want to examine the container's previous exit code. Which command provides this information?

Accepted Answer

kubectl describe pod pod-name. Option B is correct. 'kubectl describe pod' shows the container state, including the last state's exit code. Option A shows current logs. Option C shows previous logs but not the exit code. Option D shows events but not exit codes.

Answer

kubectl get events

Answer

kubectl logs pod-name --previous

Answer

kubectl logs pod-name

Question 12

Which command shows resource usage for pods and nodes in the cluster?

Accepted Answer

kubectl top pods and kubectl top nodes. The metrics server must be installed. 'kubectl top pods' shows pod CPU/memory usage, and 'kubectl top nodes' shows node usage.

Answer

kubectl cluster-info

Answer

kubectl get --sort-by=.status.capacity

Answer

kubectl describe pods and kubectl describe nodes

Question 13

Which TWO of the following could cause a Node to be in NotReady state?

Accepted Answer

The kubelet process has stopped. A Node is NotReady if the kubelet is not reporting healthy. Common causes include kubelet failure and network plugin issues.

Answer

The node has a taint that prevents scheduling

Answer

The node has insufficient disk space

Answer

The node's IP address has changed

Question 14

Which of the following is a valid command to check the status of the kubelet service on a node running systemd?

Accepted Answer

systemctl status kubelet. Option A is correct. 'systemctl status kubelet' is the appropriate command for systemd-managed services. Option B is for systemd units that are not services. Option C is for init.d. Option D is a deprecated command.

Answer

initctl status kubelet

Answer

systemctl list-units kubelet

Answer

service kubelet status

Question 15

You run 'kubectl get pods' and see a pod with status 'ImagePullBackOff'. Which of the following is a possible cause?

Accepted Answer

The container image name is misspelled. Option A is correct. ImagePullBackOff occurs when the kubelet cannot pull the container image, often due to a wrong image name, tag, or authentication issue. Options B, C, and D cause other pod states.

Answer

The node has a disk pressure condition

Answer

The pod's resource limits are too low

Answer

The pod's liveness probe is failing