Homework

Task 1: Raw Manifests vs Helm — Side-by-Side Comparison

Goal: Experience the difference between deploying with raw kubectl apply and deploying with Helm.

Instructions

1. Create a directory called raw-nginx/ and write three YAML manifests by hand:
   • deployment.yaml — an NGINX Deployment with 1 replica
   • service.yaml — a ClusterIP Service targeting port 80
   • configmap.yaml — a ConfigMap with a custom index.html containing "Hello from raw kubectl!"
2. Deploy with: kubectl apply -f raw-nginx/
3. Verify it works: kubectl port-forward svc/raw-nginx 8081:80 and open http://localhost:8081
4. Now deploy the same NGINX via Helm: helm install helm-nginx bitnami/nginx --set service.type=ClusterIP
5. Write a short comparison (100–200 words) covering:
   • How many commands and files each approach required
   • What happens if you need to change the replica count in each approach
   • How you would roll back each approach
6. Clean up both deployments:

   kubectl delete -f raw-nginx/
   helm uninstall helm-nginx

Self-check

• ✓ You created and deployed three raw YAML manifests successfully.
• ✓ You deployed the same app via Helm with a single command.
• ✓ Your comparison addresses all three points (files/commands, updates, rollbacks).

Task 2: Explore Artifact Hub

Goal: Learn to evaluate and discover community charts on Artifact Hub.

Instructions

Visit artifacthub.io and find 5 Helm charts for different use cases. For each chart, document:

1. Chart name and publisher
2. What the chart deploys (one sentence)
3. Current chart version and app version
4. Whether the publisher is verified
5. Number of stars (approximate)

Deliverable

A table in this format:

Chart	Publisher	Purpose	Chart Version	Verified?
nginx	Bitnami	NGINX web server	18.x.x	Yes
...	...	...	...	...

Self-check

• ✓ You have 5 distinct charts from at least 3 different categories.
• ✓ Each entry includes all five requested fields.
• ✓ At least one chart is from a non-Bitnami publisher.

Task 3: Upgrade and Rollback Cycle

Goal: Practice the Helm release lifecycle — install, upgrade, rollback, and history inspection.

Instructions

1. Install NGINX with 1 replica:

   helm install cycle-nginx bitnami/nginx \
     --set service.type=ClusterIP \
     --set replicaCount=1

2. Verify the deployment has 1 pod:

   kubectl get pods -l app.kubernetes.io/instance=cycle-nginx

3. Upgrade to 3 replicas:

   helm upgrade cycle-nginx bitnami/nginx \
     --set service.type=ClusterIP \
     --set replicaCount=3

4. Verify 3 pods are running:

   kubectl get pods -l app.kubernetes.io/instance=cycle-nginx

5. View the release history:

   helm history cycle-nginx

6. Roll back to revision 1 (1 replica):

   helm rollback cycle-nginx 1

7. Verify the rollback — should be back to 1 pod:

   kubectl get pods -l app.kubernetes.io/instance=cycle-nginx
   helm history cycle-nginx

8. Clean up:

   helm uninstall cycle-nginx

Questions to Answer

1. After the rollback, how many revisions does helm history show? Why?
2. What is the status of revision 2 after the rollback?
3. If you ran helm rollback cycle-nginx 2 after step 7, what would happen?

Self-check

• ✓ You completed the full install → upgrade → rollback cycle.
• ✓ helm history shows 3 revisions after the rollback (install, upgrade, rollback).
• ✓ You can explain that a rollback creates a new revision rather than deleting old ones.