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Aisalkyn Aidarova
Aisalkyn Aidarova

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CKA DEPLOYMENT & SERVICE LAB #2

#devops #kubernetes #cli #tutorial

GLOBAL RULES

  • Do NOT use kubectl edit
  • Do NOT recreate resources unless asked
  • Fix issues using kubectl patch / set / scale / rollout
  • Namespace must be used
  • Treat this like a real CKA exam

🟢 BASELINE (RUN ON EVERY MACHINE)

Step 0 — Start cluster 

minikube start --driver=docker
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Step 1 — Namespace 

kubectl create namespace cka-lab
kubectl config set-context --current --namespace=cka-lab
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Step 2 — Apply BASE WORKLOAD (DO NOT MODIFY) 

kubectl apply -f - <<EOF
apiVersion: apps/v1
kind: Deployment
metadata:
  name: web-app
spec:
  replicas: 4
  selector:
    matchLabels:
      app: web
  template:
    metadata:
      labels:
        app: web
    spec:
      containers:
      - name: nginx
        image: nginx:1.25
        ports:
        - containerPort: 80
EOF
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Step 3 — Apply BASE SERVICE (DO NOT MODIFY) 

kubectl apply -f - <<EOF
apiVersion: v1
kind: Service
metadata:
  name: web-svc
spec:
  selector:
    app: web
  ports:
  - port: 80
    targetPort: 80
  type: ClusterIP
EOF
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Step 4 — Traffic test pod (keep running) 

kubectl run traffic --image=busybox -it --rm -- sh
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Inside:

while true; do
  wget -qO- web-svc
  echo "-----"
  sleep 1
done
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🧪 TASK 1 — ROLLING UPDATE MISCONFIGURATION

PROBLEM SETUP 

kubectl patch deployment web-app -p '
{
  "spec": {
    "strategy": {
      "type": "RollingUpdate",
      "rollingUpdate": {
        "maxUnavailable": 4,
        "maxSurge": 0
      }
    }
  }
}'
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TASK

  • Fix the deployment strategy
  • Ensure no downtime during image updates

SUCCESS CRITERIA

  • Traffic loop never stops
  • At least one pod always available

🧪 TASK 2 — BROKEN IMAGE DEPLOYMENT

PROBLEM SETUP 

kubectl set image deployment/web-app nginx=nginx:doesnotexist
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TASK

  • Restore the deployment to a healthy state
  • Do NOT delete the deployment

SUCCESS CRITERIA

  • All pods Running
  • No CrashLoopBackOff
  • Traffic loop stable

🧪 TASK 3 — MISSING READINESS PROBE

PROBLEM SETUP 

kubectl patch deployment web-app --type=json -p='[
  {
    "op": "remove",
    "path": "/spec/template/spec/containers/0/readinessProbe"
  }
]'
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TASK

  • Ensure traffic is only sent to ready pods
  • Do NOT restart the cluster

SUCCESS CRITERIA

  • During rollout, traffic never hits unready pods

🧪 TASK 4 — SERVICE TRAFFIC FAILURE

PROBLEM SETUP 

kubectl patch svc web-svc -p '
{
  "spec": {
    "selector": {
      "app": "wrong"
    }
  }
}'
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TASK

  • Restore service traffic
  • Do NOT recreate the service

SUCCESS CRITERIA

  • Endpoints populated
  • Traffic loop resumes

🧪 TASK 5 — CANARY DEPLOYMENT (TRAFFIC LEAK)

PROBLEM SETUP 

kubectl create deployment web-app-canary --image=nginx:1.27 --replicas=1
kubectl label deployment web-app-canary track=canary
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TASK

  • Canary must receive traffic
  • Stable workload must remain untouched

SUCCESS CRITERIA

  • Service routes traffic to both versions
  • No service recreation

🧪 TASK 6 — CANARY ROLLBACK

PROBLEM SETUP

(canary from previous task is faulty)

TASK

  • Remove canary from traffic immediately
  • Stable version must continue serving traffic

SUCCESS CRITERIA

  • Traffic uninterrupted
  • Only stable pods receive traffic

🧪 TASK 7 — PAUSED ROLLOUT INCIDENT

PROBLEM SETUP 

kubectl rollout pause deployment web-app
kubectl set image deployment/web-app nginx=nginx:1.26
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TASK

  • Identify why rollout is stuck
  • Complete the deployment

SUCCESS CRITERIA

  • New image fully deployed
  • Deployment not paused

🧪 TASK 8 — NODEPORT ACCESS FAILURE

PROBLEM SETUP 

kubectl patch svc web-svc -p '
{
  "spec": {
    "type": "NodePort"
  }
}'
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Traffic still unreachable.

TASK

  • Make application reachable from browser
  • Do NOT recreate Service or Deployment

SUCCESS CRITERIA

  • Browser access works
  • NodePort correctly assigned

🧪 TASK 9 — SCALING INCIDENT

PROBLEM SETUP 

kubectl scale deployment web-app --replicas=0
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TASK

  • Restore service availability
  • Do NOT recreate pods manually

SUCCESS CRITERIA

  • Pods running
  • Traffic restored

🧪 TASK 10 — FINAL CLEANUP

TASK

  • Remove all resources created in this lab
  • Namespace must be empty

SUCCESS CRITERIA 

kubectl get all
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