CKAD -Exam questions pattern.

Recently I had appeared for CKAD exam and here I am sharing some questions those I remembered plus some tips .

CKAD exam based on the curriculum

• Core Concepts (13%)
• Multi-Container Pods (10%)
• Pod Design (20%)
• State Persistence (8%)
• Configuration (18%)
• Observability (18%)
• Services and Networking (13%)

Tips for exam

• Skip the questions with weightage 2%-3% if it takes a long time , as you will waste you time to understand these kinds of questions .
• There will be total 19 questions in the exam and you can solve any question at any time .
• Notepad or any other software is not allowed to open apart from 2 google chrome tabs .
• If you want to copy aliases or any other steps then copy it before hand and once you get access then paste it internal notepad of exam screen .
• Try to solve questions using imperative commands .
• If you want to copy aliases then , make sure you copy it first and when you get exam screen you can paste in internal notepad.
• Useful allowed Documentation links During exam
  https://kubernetes.io/docs/
  https://kubernetes.io/docs/reference/generated/kubectl/kubectl-commands#-em-deployment-em-
• Most useful commands :(apart below you can make aliases of commands )

— dry-run=client -o yaml
kubectl run busybox — image=busybox — restart=Never — /bin/sh -c ‘i=0; while true; do echo “$i: $(date)”; i=$((i+1)); sleep 1; done’
Kubectl create -f somefile.yaml
kubectl set image …
kubectl expose deployment …

set number relativenumber expandtab ts=2 sts=2 sw2

Sample questions from exam , there will be similar types of questions in the exam .

1. Create pod to run command using busybox image .Command — “sleep 3600; ls“

kubectl run busybox --image=busybox --restart=Never --dry-run -o yaml -- bin/sh -c "sleep 3600; ls"

2. Fix image issue of deployment

 kubectl set image deploy/webapp image1=image2

3. Expose Node port service of deployment

apiVersion: v1
kind: Service
metadata:
  name: my-service
spec:
  type: NodePort
  selector:
    app: MyApp
  ports:
      # By default and for convenience, the `targetPort` is set to the same value as the `port` field.
    - port: 80
      targetPort: 80
      # Optional field
      # By default and for convenience, the Kubernetes control plane will allocate a port from a range (default: 30000-32767)
      nodePort: 300074. Create pod and store the logs of pod to somefile

4. Create pod and store the logs of pod to somefile

kubectl run logWriter --image=logWriter
kubectl logs logWriter > \path\somefile.log

5. Find out the pod which is failing in random namespace , here you need to find out pod name and namespace which is failing and save it into given file.

Find failing pod from all namespaces 
kubectl get pod -A |grep CrashLoopBackOff
Get the namespace and pod name in given file name

6. Update Deployment to add ServiceAccount which is already created for you .

kubectl edit deployment/mydeployment 
add service account field under pod-> spec
 spec:
      containers:
      - name: nginx
        image: nginx:1.14.2
        ports: 
      serviceAccountName: build-robot

7. Create ConfigMap — from-literals =key=value and use it as ENV varible in POD.

kubectl create configmap special-config --from-literal=special.how=very
apiVersion: v1
kind: Pod
metadata:
  name: dapi-test-pod
spec:
  containers:
    - name: test-container
      image: k8s.gcr.io/busybox
      command: [ "/bin/sh", "-c", "env" ]
      env:
        # Define the environment variable
        - name: SPECIAL_LEVEL_KEY
          valueFrom:
            configMapKeyRef:
              # The ConfigMap containing the value you want to assign to SPECIAL_LEVEL_KEY
              name: special-config
              # Specify the key associated with the value
              key: special.how
  restartPolicy: Never

8. Create secret — from-literals=key=value and use it in pod .

kubectl create secret generic my-secret --from-literal=key1=supersecret --from-literal=key2=topsecret
Create Pod
apiVersion: v1
kind: Pod
metadata:
  name: mypod
spec:
  containers:
  - name: mypod
    image: redis
    volumeMounts:
    - name: foo
      mountPath: "/etc/foo"
      readOnly: true
  volumes:
  - name: foo
    secret:
      secretName: my-secret

9. From Given namespace find out the pod name which is consuming top cpu

kubectl top pod -n <namespaceName>

10. Create pod which request minimum cpu of 300Mi and minimum memory of 2Gi

// add the resources section and create
apiVersion: v1
kind: Pod
metadata:
  creationTimestamp: null
  labels:
    run: nginx
  name: nginx
spec:
  containers:
  - image: nginx
    name: nginx
    resources:
      requests:
        memory: "2Gi"
        cpu: "300Mi"
  dnsPolicy: ClusterFirst
  restartPolicy: Never
status: {}

11. Create readiness probe for running pod

kubectl edit pod podname
Add below configaration in yaml and save
 readinessProbe:
      initialDelaySeconds: 20
      periodSeconds: 25
      httpGet:
        path: /
        port: 80

12. Create Storage with host path , then create claim for same and also create pod to use it

Create PV using below definition 
apiVersion: v1
kind: PersistentVolume
metadata:
  name: pv-hostPath
  labels:
    type: local
spec:
  storageClassName: manual
  capacity:
    storage: 1Gi
  accessModes:
    - ReadWriteOnce
  hostPath:
    path: "/mnt/data"
    
kubectl create -f task-pv-volume.yaml
---------------------------------------------------------
// task-pv-claim.yaml
apiVersion: v1
kind: PersistentVolumeClaim
metadata:
  name: pv-claim-hostPath
spec:
  storageClassName: manual
  accessModes:
    - ReadWriteOnce
  resources:
    requests:
      storage: 300Mi
      
kubectl create -f task-pv-claim.yaml
---------------------------------------------------------
apiVersion: v1
kind: Pod
metadata:
  name: redis
spec:
  containers:
  - name: redis
    image: redis
    volumeMounts:
      - mountPath: "/usr/share/path/html"
        name: pv-claim-hostPath
  volumes:
  - name: pv-claim-hostPath
    persistentVolumeClaim:
        claimName: task-pv-claim
    
kubectl create -f redis-storage.yaml

13. Create Job which will run every 10 second using busybox and it should complete in 10 seconds .

apiVersion: batch/v1beta1
kind: CronJob
metadata:
  name: task-cronjob
spec:
  schedule: "*/1 * * * *"
  jobTemplate:
    spec:
      template:
        spec:
        activeDeadlineSeconds: 10  
        containers:
          - name: hello
            image: busybox
            imagePullPolicy: IfNotPresent
            args:
            - /bin/sh
            - -c
            - date; Hellow from Cronjob
          restartPolicy: OnFailure
    
kubectl create -f cronjob.yaml

14. Create NP to allowed frontend and backend pod to communicate eachother

apiVersion: networking.k8s.io/v1
kind: NetworkPolicy
metadata:
  name: simple-policy
  namespace: default
spec:
  podSelector:
    matchLabels:
      app: frontend
  policyTypes:
  - Ingress
  - Egress
  ingress:
  - from:
    - namespaceSelector:
        matchLabels:
          name: backend-namespace
    - podSelector:
        matchLabels:
          app: backend
    ports:
    - protocol: TCP
      port: 6379
  egress:
  - to:
    - namespaceSelector:
        matchLabels:
          name: frontend-namespace
    - podSelector:
        matchLabels:
          app: frontend
    ports:
    - protocol: TCP
      port: 5978