Linux Foundation CKA Online Practice Questions and Exam Preparation

Linux Foundation CKA Online Questions & Answers

• Question 31:

  SIMULATION

  Create 2 nginx image pods in which one of them is labelled with env=prod and another one labelled with env=dev and verify the same.

  Correct Answer. Check the answer in explanation.
  Check the answer in explanation.

  ---

  kubectl run --generator=run-pod/v1 --image=nginx -- labels=env=prod nginx-prod --dry-run -o yaml > nginx-prodpod.yaml Now, edit nginx-prod-pod.yaml file and remove entries like "creationTimestamp:

  null" "dnsPolicy: ClusterFirst"

  vim nginx-prod-pod.yaml

  apiVersion: v1

  kind: Pod

  metadata:

  labels:

  env: prod

  name: nginx-prod

  spec:

  containers:

  image: nginx name: nginx-prod restartPolicy: Always # kubectl create -f nginx-prod-pod.yaml kubectl run --generator=run-pod/v1 --image=nginx -labels=env=dev nginx-dev --dry-run -o yaml > nginx-dev-pod.yaml apiVersion: v1 kind: Pod metadata: labels: env: dev name: nginx-dev spec: containers:

  image: nginx name: nginx-dev restartPolicy: Always # kubectl create -f nginx-prod-dev.yaml Verify : kubectl get po --show-labels kubectl get po -l env=prod kubectl get po -l env=dev

• Question 32:

  SIMULATION List all the pods showing name and namespace with a json path expression

  Correct Answer. Check the answer in explanation.
  Check the answer in explanation.

  ---

  kubectl get pods -o=jsonpath="{.items[*]['metadata.name', 'metadata.namespace']}"

• Question 33:

  SIMULATION

  

  Task

  Scale the deployment presentation to 6 pods.

  Correct Answer. Check the answer in explanation.
  Check the answer in explanation.

  ---

  Solution:

  

• Question 34:

  SIMULATION

  You must connect to the correct host.

  Failure to do so may result in a zero score.

  [candidate@base] $ ssh cka000037

  Context

  A legacy app needs to be integrated into the Kubernetes built-in logging architecture (i.e., kubectl logs). Adding a streaming co-located container is a good and common way to accomplish this requirement.

  Task

  Update the existing Deployment synergy-leverager, adding a co-located container named sidecar using the busybox:stable image to the existing Pod.

  The new co-located container has to run the following command:

  /bin/sh -c "tail -n+1 -f /var/log/synergy-leverager.log"

  Use a volume mounted at /var/log to make the log file synergy-leverager.log available to the co-located container.

  Do not modify the specification of the existing container other than adding the required volume mount.

  Failure to do so may result in a reduced score.

  Correct Answer. Check the answer in explanation.
  Check the answer in explanation.

  ---

  Explanation Task Summary

  SSH into the correct node: cka000037

  Modify existing deployment synergy-leverager

  Add a sidecar container:

  Name: sidecar

  Image: busybox:stable

  Command:

  /bin/sh -c "tail -n+1 -f /var/log/synergy-leverager.log"

  Use a shared volume mounted at /var/log

  Don't touch existing container config except adding volume mount

  Step-by-Step Solution:

  1. SSH into the correct node

  ssh cka000037

  Skipping this will result in a zero score.

  2. Edit the deployment

  kubectl edit deployment synergy-leverager

  This opens the deployment YAML in your default editor (vi or similar).

  3. Modify the spec as follows

  Inside the spec.template.spec, do these 3 things:

  #A. Define a shared volume

  Add under volumes: (at the same level as containers:): volumes:

  -name: log-volume

  emptyDir: {}

  #B. Add volume mount to the existing container

  Locate the existing container under containers: and add this: volumeMounts:

  -name: log-volume

  mountPath: /var/log

  Do not change any other configuration for this container.

  #C. Add the sidecar container

  Still inside containers:, add the new container definition after the first one:

  -name: sidecar image: busybox:stable command:

  -/bin/sh

  - -c

  -"tail -n+1 -f /var/log/synergy-leverager.log"

  volumeMounts:

  -name: log-volume

  mountPath: /var/log

  Final YAML Structure Example

  spec: containers:

  -

  name: main-container

  image: your-existing-image

  volumeMounts:

  -

  name: log-volume

  mountPath: /var/log

  -

  name: sidecar

  image: busybox:stable

  command:

  -/bin/sh

  - -c

  -"tail -n+1 -f /var/log/synergy-leverager.log"

  volumeMounts:

  -name: log-volume

  mountPath: /var/log

  volumes:

  -name: log-volume

  emptyDir: {}

  Save and exit

  If using vi or vim, type:

  :wq

  5. Verify

  Check the updated pods:

  kubectl get pods -l app=synergy-leverager

  Pick a pod name and describe it:

  kubectl describe pod

  Confirm:

  2 containers running (main-container + sidecar)

  Volume mounted at /var/log

  Summary Commands

  ssh cka000037 kubectl edit deployment synergy-leverager # Modify as explained above kubectl get pods -l app=synergy-leverager kubectl describe pod

• Question 35:

  SIMULATION

  

  Task

  Scale the deployment webserver to 3 pods.

  Correct Answer. Check the answer in explanation.
  Check the answer in explanation.

  ---

  Solution:

  

• Question 36:

  SIMULATION

  You must connect to the correct host. Failure to do so may result in a zero score. [candidate@base] $ ssh Cka000046

  Task

  First, create a new StorageClass named local-path for an existing provisioner named rancher.io/local-path .

  Set the volume binding mode to WaitForFirstConsumer .

  Not setting the volume binding mode or setting it to anything other than WaitForFirstConsumer may result in a reduced score.

  Next, configure the StorageClass local-path as the default StorageClass .

  Correct Answer. Check the answer in explanation.
  Check the answer in explanation.

  ---

  Solution:

  

  

• Question 37:

  SIMULATION

  

  Task

  Create a persistent volume with name app-data , of capacity 1Gi and access mode ReadOnlyMany. The type of volume is hostPath and its location is /srv/app-data .

  Correct Answer. Check the answer in explanation.
  Check the answer in explanation.

  ---

  #vi pv.yaml apiVersion: v1 kind: PersistentVolume metadata: name: app-config spec: capacity: storage: 1Gi accessModes:

  -ReadOnlyMany hostPath: path: /srv/app-config # kubectl create -f pv.yaml

• Question 38:

  SIMULATION

  You must connect to the correct host.

  Failure to do so may result in a zero score.

  [candidate@base] $ ssh Cka000022

  Task

  Reconfigure the existing Deployment front-end in namespace spline-reticulator to expose port 80/tcp of the existing container nginx .

  Create a new Service named front-end-svc exposing the container port 80/tcp .

  Configure the new Service to also expose the individual Pods via a NodePort .

  Correct Answer. Check the answer in explanation.
  Check the answer in explanation.

  ---

  Step-by-step solution:

  1. SSH into the node:

  ssh cka000022

  2. Edit the deployment to expose port 80 of the existing container nginx:

  kubectl edit deployment front-end -n spline-reticulator Inside the container spec, ensure the following is present: containers:

  -name: nginx image: nginx ports:

  -containerPort: 80

  Do not change anything else. Just add the ports section if it's missing.

  3. Create a NodePort Service named front-end-svc to expose port 80 of the Pods:

  kubectl expose deployment front-end \ --port=80 \ --target-port=80 \ --type=NodePort \ --name=front-end-svc \ -n spline-reticulator

  4. Verify:

  kubectl get svc front-end-svc -n spline-reticulator kubectl describe svc front-end-svc -n spline-reticulator You should see: Type: NodePort Port: 80/TCP TargetPort: 80 Selector: Matches the front-end Pods

• Question 39:

  SIMULATION

  List "nginx-dev" and "nginx-prod" pod and delete those pods

  Correct Answer. Check the answer in explanation.
  Check the answer in explanation.

  ---

  kubect1 get pods -o wide

  kubectl delete po "nginx-dev"kubectl delete po "nginx-prod"

• Question 40:

  SIMULATION

  Create a pod as follows:

  Name: mongo Using Image: mongo In a new Kubernetes namespace named: my-website

  Correct Answer. Check the answer in explanation.
  Check the answer in explanation.

  ---

  Solution: