Part 1 Cumulative Quiz: Application Design and Build

Time Limit: 25 minutes (simulating exam pressure)

Passing Score: 80% (8/10 questions)

This quiz tests your mastery of:

• Container images
• Jobs and CronJobs
• Multi-container pods (sidecar, init, ambassador)
• Volumes (emptyDir, ConfigMap, Secret, PVC)

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Instructions

1. Try each question without looking at answers
2. Time yourself—speed matters for CKAD
3. Use only kubectl and kubernetes.io/docs
4. Check answers after completing all questions

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Questions

Question 1: Image Pull Issue

[2 minutes]

A pod is stuck in ImagePullBackOff:

k get pods
# NAME      READY   STATUS             RESTARTS   AGE
# broken    0/1     ImagePullBackOff   0          5m

Identify the issue and fix it. The pod should run nginx version 1.21.

Answer

# Diagnose
k describe pod broken | grep -A5 Events
# Look for: failed to pull image

# Check current image
k get pod broken -o jsonpath='{.spec.containers[0].image}'
# Probably wrong tag or typo

# Fix (delete and recreate or patch)
k delete pod broken
k run broken --image=nginx:1.21

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Question 2: Create a Job

[2 minutes]

Create a Job named backup-job that:

• Uses image busybox
• Runs command echo "Backup completed at $(date)"
• Has a backoff limit of 2

Answer

# Generate and modify
k create job backup-job --image=busybox --dry-run=client -o yaml -- sh -c 'echo "Backup completed at $(date)"' > job.yaml

# Add backoffLimit: 2 to spec, then apply
# Or directly:
cat << 'EOF' | k apply -f -
apiVersion: batch/v1
kind: Job
metadata:
  name: backup-job
spec:
  backoffLimit: 2
  template:
    spec:
      containers:
      - name: backup
        image: busybox
        command: ["sh", "-c", "echo Backup completed at $(date)"]
      restartPolicy: Never
EOF

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Question 3: CronJob Schedule

[2 minutes]

Create a CronJob named cleanup that:

• Runs every 30 minutes
• Uses image busybox
• Echoes “Cleanup running”
• Has concurrencyPolicy: Forbid

Answer

# Imperative then patch
k create cronjob cleanup --image=busybox --schedule="*/30 * * * *" -- echo "Cleanup running"
k patch cronjob cleanup -p '{"spec":{"concurrencyPolicy":"Forbid"}}'

# Or YAML:
cat << 'EOF' | k apply -f -
apiVersion: batch/v1
kind: CronJob
metadata:
  name: cleanup
spec:
  schedule: "*/30 * * * *"
  concurrencyPolicy: Forbid
  jobTemplate:
    spec:
      template:
        spec:
          containers:
          - name: cleanup
            image: busybox
            command: ["echo", "Cleanup running"]
          restartPolicy: OnFailure
EOF

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Question 4: Multi-Container Pod

[3 minutes]

Create a pod named sidecar-pod with:

• Main container: nginx image
• Sidecar container: busybox image, running tail -f /var/log/nginx/access.log
• Both containers share a volume at /var/log/nginx

Answer

apiVersion: v1
kind: Pod
metadata:
  name: sidecar-pod
spec:
  containers:
  - name: nginx
    image: nginx
    volumeMounts:
    - name: logs
      mountPath: /var/log/nginx
  - name: sidecar
    image: busybox
    command: ["tail", "-f", "/var/log/nginx/access.log"]
    volumeMounts:
    - name: logs
      mountPath: /var/log/nginx
  volumes:
  - name: logs
    emptyDir: {}

k apply -f sidecar-pod.yaml

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Question 5: Init Container

[3 minutes]

Create a pod named init-pod that:

• Has an init container that creates file /work/ready.txt with content “initialized”
• Main container (nginx) mounts the same directory

Answer

apiVersion: v1
kind: Pod
metadata:
  name: init-pod
spec:
  initContainers:
  - name: init
    image: busybox
    command: ["sh", "-c", "echo initialized > /work/ready.txt"]
    volumeMounts:
    - name: workdir
      mountPath: /work
  containers:
  - name: nginx
    image: nginx
    volumeMounts:
    - name: workdir
      mountPath: /work
  volumes:
  - name: workdir
    emptyDir: {}

Verify:

k exec init-pod -- cat /work/ready.txt

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Question 6: ConfigMap as Volume

[2 minutes]

Create a ConfigMap named web-content with key index.html containing “Hello CKAD”.

Then create a pod named web-server that:

• Uses nginx image
• Mounts the ConfigMap at /usr/share/nginx/html

Answer

# Create ConfigMap
k create cm web-content --from-literal=index.html="Hello CKAD"

# Create pod
cat << 'EOF' | k apply -f -
apiVersion: v1
kind: Pod
metadata:
  name: web-server
spec:
  containers:
  - name: nginx
    image: nginx
    volumeMounts:
    - name: html
      mountPath: /usr/share/nginx/html
  volumes:
  - name: html
    configMap:
      name: web-content
EOF

# Verify
k exec web-server -- curl localhost

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Question 7: Secret Volume

[2 minutes]

Create a Secret named db-creds with:

• username=admin
• password=secret123

Mount it read-only in a pod named secret-pod at /etc/db

Answer

# Create secret
k create secret generic db-creds \
  --from-literal=username=admin \
  --from-literal=password=secret123

# Create pod
cat << 'EOF' | k apply -f -
apiVersion: v1
kind: Pod
metadata:
  name: secret-pod
spec:
  containers:
  - name: app
    image: busybox
    command: ["sleep", "3600"]
    volumeMounts:
    - name: secrets
      mountPath: /etc/db
      readOnly: true
  volumes:
  - name: secrets
    secret:
      secretName: db-creds
EOF

# Verify
k exec secret-pod -- cat /etc/db/password

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Question 8: Parallel Job

[3 minutes]

Create a Job named parallel-job that:

• Runs 6 completions
• With parallelism of 2
• Uses busybox to echo “Processing”

Answer

apiVersion: batch/v1
kind: Job
metadata:
  name: parallel-job
spec:
  completions: 6
  parallelism: 2
  template:
    spec:
      containers:
      - name: worker
        image: busybox
        command: ["echo", "Processing"]
      restartPolicy: Never

Verify:

k get pods -l job-name=parallel-job -w
# Should see 2 pods at a time, 6 total

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Question 9: Fix Multi-Container Pod

[3 minutes]

The following pod won’t start. Identify and fix the issue:

apiVersion: v1
kind: Pod
metadata:
  name: broken-multi
spec:
  initContainers:
  - name: init
    image: busybox
    command: ["sleep", "infinity"]  # Problem!
  containers:
  - name: main
    image: nginx

Answer

Issue: The init container runs sleep infinity and never exits. Init containers must complete (exit 0) for main containers to start.

Fix: Change the init container command to something that completes:

initContainers:
- name: init
  image: busybox
  command: ["echo", "Init done"]

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Question 10: PVC and Pod

[3 minutes]

Create a PVC named data-pvc requesting 100Mi storage.

Then create a pod named storage-pod that:

• Uses nginx image
• Mounts the PVC at /data

Write a file to /data/test.txt to verify persistence.

Answer

# Create PVC
cat << 'EOF' | k apply -f -
apiVersion: v1
kind: PersistentVolumeClaim
metadata:
  name: data-pvc
spec:
  accessModes: ["ReadWriteOnce"]
  resources:
    requests:
      storage: 100Mi
EOF

# Create pod
cat << 'EOF' | k apply -f -
apiVersion: v1
kind: Pod
metadata:
  name: storage-pod
spec:
  containers:
  - name: nginx
    image: nginx
    volumeMounts:
    - name: storage
      mountPath: /data
  volumes:
  - name: storage
    persistentVolumeClaim:
      claimName: data-pvc
EOF

# Verify
k exec storage-pod -- sh -c "echo 'persistent' > /data/test.txt"
k exec storage-pod -- cat /data/test.txt

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Scoring

Questions Correct	Score	Status
10/10	100%	Excellent - Ready for exam
8-9/10	80-90%	Good - Minor review needed
6-7/10	60-70%	Review weak areas
<6/10	<60%	Revisit Part 1 modules

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Cleanup

k delete pod broken sidecar-pod init-pod web-server secret-pod storage-pod broken-multi 2>/dev/null
k delete job backup-job parallel-job 2>/dev/null
k delete cronjob cleanup 2>/dev/null
k delete cm web-content 2>/dev/null
k delete secret db-creds 2>/dev/null
k delete pvc data-pvc 2>/dev/null

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Next Part

Part 2: Application Deployment - Deployments, Helm, Kustomize, and deployment strategies.