CKAD — Helm & Kustomize Lab

Lab 1: Helm Install, Upgrade, Rollback

Practice the full Helm lifecycle — install, inspect, upgrade, view history, roll back, and uninstall.

# Add the bitnami repo
helm repo add bitnami https://charts.bitnami.com/bitnami
helm repo update

# Install Redis with custom values
helm install my-redis bitnami/redis \
  --set architecture=standalone \
  --set auth.password=mypassword

# Check the release
helm list
helm status my-redis

# Upgrade to a specific chart version
helm upgrade my-redis bitnami/redis \
  --set architecture=standalone \
  --set auth.password=mypassword \
  --set replica.replicaCount=0

# Check history
helm history my-redis

# Roll back to revision 1
helm rollback my-redis 1

# Clean up
helm uninstall my-redis

What to observe:

• helm list shows the release with its revision number
• helm history shows all revisions and their status
• After helm rollback, the revision number increments (it creates a new revision)

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Lab 2: Kustomize Base and Overlay

Build a Kustomize project from scratch with a base and two overlays (dev and prod).

# Create the directory structure
mkdir -p kustomize-lab/base kustomize-lab/overlays/{dev,prod}

# Create base deployment
cat <<EOF > kustomize-lab/base/deployment.yaml
apiVersion: apps/v1
kind: Deployment
metadata:
  name: web
spec:
  replicas: 1
  selector:
    matchLabels:
      app: web
  template:
    metadata:
      labels:
        app: web
    spec:
      containers:
      - name: web
        image: nginx:1.26
        ports:
        - containerPort: 80
EOF

# Create base kustomization
cat <<EOF > kustomize-lab/base/kustomization.yaml
apiVersion: kustomize.config.k8s.io/v1beta1
kind: Kustomization
resources:
- deployment.yaml
EOF

# Create dev overlay
cat <<EOF > kustomize-lab/overlays/dev/kustomization.yaml
apiVersion: kustomize.config.k8s.io/v1beta1
kind: Kustomization
resources:
- ../../base
namePrefix: dev-
namespace: dev
images:
- name: nginx
  newTag: "1.27"
EOF

# Create prod overlay (3 replicas)
cat <<EOF > kustomize-lab/overlays/prod/kustomization.yaml
apiVersion: kustomize.config.k8s.io/v1beta1
kind: Kustomization
resources:
- ../../base
namePrefix: prod-
namespace: production
patches:
- target:
    kind: Deployment
    name: web
  patch: |
    - op: replace
      path: /spec/replicas
      value: 3
images:
- name: nginx
  newTag: "1.27"
EOF

# Preview dev
kubectl kustomize kustomize-lab/overlays/dev/
# Expected: Deployment named "dev-web" in namespace "dev" with nginx:1.27

# Preview prod
kubectl kustomize kustomize-lab/overlays/prod/
# Expected: Deployment named "prod-web" in namespace "production" with 3 replicas

# Apply dev
kubectl create namespace dev
kubectl apply -k kustomize-lab/overlays/dev/
kubectl get deployment -n dev

---

Practice Questions

Q1: Install a Helm chart named bitnami/nginx as release web-server with 3 replicas.

Show Answer

```bash helm repo add bitnami https://charts.bitnami.com/bitnami helm install web-server bitnami/nginx --set replicaCount=3 ``` Verify: ```bash helm list helm status web-server ```

Q2: You upgraded a Helm release and it broke. How do you roll back to revision 2?

Show Answer

```bash # Check history helm history my-release # Roll back to revision 2 helm rollback my-release 2 # Verify helm status my-release ```

Q3: What does kubectl apply -k overlays/prod/ do?

Show Answer

It applies all Kubernetes resources defined in the Kustomize overlay at `overlays/prod/`. Kustomize reads the `kustomization.yaml` file in that directory, resolves the base resources, applies all patches, transformations (namePrefix, namespace, labels, image overrides), and then creates/updates the resources in the cluster.

Q4: Write a kustomization.yaml that takes a base from ../../base, adds the namespace staging, and changes the image tag to v2.5.

Show Answer

```yaml apiVersion: kustomize.config.k8s.io/v1beta1 kind: Kustomization resources: - ../../base namespace: staging images: - name: myapp newTag: "v2.5" ```

Q5: What is the command to see the default values of a Helm chart before installing it?

Show Answer

```bash helm show values bitnami/nginx ``` You can also redirect to a file and edit it: ```bash helm show values bitnami/nginx > values.yaml # Edit values.yaml as needed helm install my-release bitnami/nginx -f values.yaml ```

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