Linux Foundation CKA Online Practice Questions and Exam Preparation

Linux Foundation CKA Online Questions & Answers

• Question 61:

  SIMULATION

  Check the Image version of nginx-dev pod using jsonpath

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

  ---

  kubect1 get po nginx-dev -o jsonpath='{.spec.containers[].image}{"\n"}'

• Question 62:

  SIMULATION

  Create a persistent volume with name app-data, of capacity 2Gi and access mode ReadWriteMany. 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.

  ---

  Persistent Volume A persistent volume is a piece of storage in a Kubernetes cluster. PersistentVolumes are a cluster- level resource like nodes, which don't belong to any namespace. It is provisioned by the administrator and has a particular file size. This way, a developer deploying their app on Kubernetes need not know the underlying infrastructure. When the developer needs a certain amount of persistent storage for their application, the system administrator configures the cluster so that they consume the PersistentVolume provisioned in an easy way. Creating Persistent Volume kind: PersistentVolume apiVersion:

  v1 metadata: name:app-data spec: capacity: # defines the capacity of PV we are creating storage: 2Gi #the amount of storage we are tying to claim accessModes: # defines the rights of the volume we are creating -ReadWriteMany hostPath:

  path: "/srv/app-data" # path to which we are creating the volume Challenge

  Create a Persistent Volume named app-data, with access mode ReadWriteMany, storage classname shared, 2Gi of storage capacity and the host path /srv/app-data.

  

  2. Save the file and create the persistent volume.

  3. View the persistent volume.

  

  

  Our persistent volume status is available meaning it is available and it has not been mounted yet. This status will change when we mount the persistentVolume to a persistentVolumeClaim. PersistentVolumeClaim In a real ecosystem, a system admin will create the PersistentVolume then a developer will create a PersistentVolumeClaim which will be referenced in a pod. A PersistentVolumeClaim is created by specifying the minimum size and the access mode they require from the persistentVolume. Challenge Create a Persistent Volume Claim that requests the Persistent Volume we had created above. The claim should request 2Gi. Ensure that the Persistent Volume Claim has the same storageClassName as the persistentVolume you had previously created. kind: PersistentVolume apiVersion: v1 metadata: name:app-data spec: accessModes:

  -ReadWriteMany resources: requests: storage: 2Gi storageClassName: shared

  2. Save and create the pvc njerry191@cloudshell:~ (extreme-clone-2654111)$ kubect1 create -f app-data.yaml persistentvolumeclaim/app-data created

  3. View the pvc

  4. Let's see what has changed in the pv we had initially created.

  

  

  Our status has now changed from available to bound.

  5. Create a new pod named myapp with image nginx that will be used to Mount the Persistent Volume Claim with the path /var/app/config. Mounting a Claim apiVersion: v1 kind: Pod metadata: creationTimestamp: null name: app-data spec: volumes:

  -name:congigpvc persistenVolumeClaim: claimName: app-data containers:

  -image: nginx name: app volumeMounts:

  -mountPath: "/srv/app-data " name: configpvc

• Question 63:

  SIMULATION

  Create a pod that echo "hello world" and then exists. Have the pod deleted automatically when it's completed

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

  ---

  kubectl run busybox --image=busybox -it --rm --restart=Never -- /bin/sh -c 'echo hello world' kubectl get po # You shouldn't see pod with the name "busybox"

• Question 64:

  SIMULATION

  List the nginx pod with custom columns POD_NAME and POD_STATUS

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

  ---

  kubectl get po -o=custom-columns="POD_NAME:.metadata.name, POD_STATUS:.status.containerStatuses[].state"

• Question 65:

  SIMULATION

  Create a deployment as follows:

  1. Name: nginx-app

  2. Using container nginx with version 1.11.10-alpine

  3. The deployment should contain 3 replicas

  Next, deploy the application with new version 1.11.13-alpine, by performing a rolling update. Finally, rollback that update to the previous version 1.11.10-alpine.

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

  ---

  Solution:

  

  

  

• Question 66:

  SIMULATION

  You must connect to the correct host.

  Failure to do so may result in a zero score.

  [candidate@base] $ ssh Cka000047

  Task

  A MariaDB Deployment in the mariadb namespace has been deleted by mistake. Your task is to restore the Deployment ensuring data persistence. Follow these steps:

  Create a PersistentVolumeClaim (PVC ) named mariadb in the mariadb namespace with the following specifications:

  Access mode ReadWriteOnce

  Storage 250Mi

  You must use the existing retained PersistentVolume (PV ).

  Failure to do so will result in a reduced score.

  There is only one existing PersistentVolume .

  Edit the MariaDB Deployment file located at ~/mariadb-deployment.yaml to use PVC you created in the previous step.

  Apply the updated Deployment file to the cluster.

  Ensure the MariaDB Deployment is running and stable.

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

  ---

  Explanation Step 1: SSH into the correct host

  ssh cka000047

  Step 2: Create the PersistentVolumeClaim (PVC)

  Use the specs provided:

  Name: mariadb

  Namespace: mariadb

  Access mode: ReadWriteOnce

  Storage: 250Mi

  # pvc-mariadb.yaml apiVersion: v1 kind: PersistentVolumeClaim metadata:

  name: mariadb namespace: mariadb spec: accessModes:

  -ReadWriteOnce

  resources:

  requests:

  storage: 250Mi

  Apply it:

  kubectl apply -f pvc-mariadb.yaml

  Step 3: Confirm the PVC is bound to the existing retained PV

  kubectl get pv kubectl get pvc -n mariadb

  Ensure the PVC named mariadb is Bound to the only existing Retained PV.

  Step 4: Edit the Deployment YAML file

  Edit ~/mariadb-deployment.yaml and update the volume section to mount the PVC.

  Add inside the spec:

  spec:

  containers:

  -

  name: mariadb

  image: mariadb

  volumeMounts:

  -

  name: mariadb-storage

  mountPath: /var/lib/mysql

  volumes:

  -name: mariadb-storage

  persistentVolumeClaim:

  claimName: mariadb

  Ensure this is placed under spec.template.spec in the deployment file.

  Step 5: Apply the updated Deployment

  kubectl apply -f ~/mariadb-deployment.yaml Step 6: Confirm the Deployment is running and stable kubectl get pods -n mariadb

  kubectl describe pod -n mariadb kubectl get deployment mariadb -n mariadb All pods should be in Running state, and the PVC should remain Bound.

• Question 67:

  SIMULATION Create a Kubernetes secret as follows:

  Name: super-secret

  password: bob

  Create a pod named pod-secrets-via-file, using the redis Image, which mounts a secret named super- secret at /secrets. Create a second pod named pod-secrets-via-env, using the redis Image, which exports password as CONFIDENTIAL

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

  ---

  Solution:

  

  

  

• Question 68:

  SIMULATION

  Create a nginx pod with label env=test in engineering namespace .

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

  ---

  kubectl run nginx --image=nginx --restart=Never --labels=env=test --namespace=engineering --dry- run -o yaml > nginx-pod.yaml kubectl run nginx --image=nginx --restart=Never --labels=env=test --namespace=engineering --dry- run -o yaml | kubectl create -n engineering -f YAML File:

  apiVersion: v1 kind: Pod metadata: name: nginx namespace: engineering labels: env: test spec: containers:

  -name: nginx image: nginx imagePullPolicy: IfNotPresent restartPolicy: Never

  kubectl create -f nginx-pod.yaml

• Question 69:

  SIMULATION

  

  Task

  Reconfigure the existing deployment front-end and add a port specification named http exposing port 80/tcp of the existing container nginx. Create a new service named front-end-svc exposing the container port http.

  Configure the new service to also expose the individual Pods via a NodePort on the nodes on which they are scheduled.

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

  ---

  Solution:

  

  

• Question 70:

  SIMULATION

  List all the pods sorted by name

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

  ---

  kubect1 get pods --sort-by=.metadata.name