Advanced Kubernetes Part 2: Helm Basics – Packaging & Managing Apps¶

By now you've hand-written Deployments, Services, ConfigMaps, Secrets, etc.
That's great for learning, but in real projects, repeating that YAML for every app (or version) is painful and error-prone.

Helm is Kubernetes' official package manager.
It bundles YAML templates + values into charts, reusable, versioned packages.
You can install, upgrade, rollback, or delete entire apps with one command.

Pizza chain analogy:
- Hand-written YAML = writing a new recipe from scratch every time
- Helm chart = a pre-made recipe book with fill-in-the-blanks (values.yaml)
→ Change sauce type or number of ovens → run helm upgrade → done

Goal for this section¶

Install Helm locally
Deploy nginx using the official Bitnami nginx chart
Customize it (replicas, config)
Upgrade & rollback
See how much easier this is than raw kubectl

Step 1: Install Helm¶

Helm is just a client binary, no cluster-side component.

choco install kubernetes-helm

brew install helm

curl https://raw.githubusercontent.com/helm/helm/main/scripts/get-helm-3 | bash

Verify:

helm version

→ You should see something like version.BuildInfo{Version:"v3.16.x"...}

Step 2: Add a chart repository¶

Helm charts are hosted in repos (like Docker Hub for images).

Add the popular Bitnami repo (lots of high-quality charts):

helm repo add bitnami https://charts.bitnami.com/bitnami
helm repo update

Search for nginx:

helm search repo nginx

→ You'll see bitnami/nginx (official, well-maintained)

Step 3: Install nginx via Helm¶

Run:

helm install my-nginx bitnami/nginx \
  --set replicaCount=3 \
  --set service.type=NodePort

What this does:

• Installs the chart named my-nginx
• Overrides defaults: 3 replicas, NodePort service
• Helm creates Deployment, Service, ConfigMap, etc. automatically

Check:

kubectl get all
helm list

→ See the 3 Pods, Service, and Helm release.

Open in browser:

minikube service my-nginx-nginx

→ Welcome to nginx!

Step 4: Customize with values.yaml (real power)¶

Create a file custom-values.yaml:

replicaCount: 5

image:
  tag: "1.25"           # pin version

service:
  type: NodePort
  nodePorts:
    http: 30080         # fixed port (optional)

ingress:
  enabled: true
  hostname: nginx.local
  path: /

Upgrade the release:

helm upgrade my-nginx bitnami/nginx -f custom-values.yaml

→ Replicas → 5, Ingress created (if you enabled Ingress addon earlier), port fixed

Check:

kubectl get pods   # 5 replicas now
helm get values my-nginx   # see applied values

Step 5: Rollback if something breaks¶

Simulate a bad change : set wrong image tag:

helm upgrade my-nginx bitnami/nginx --set image.tag=bad-tag

Pods will fail (ImagePullBackOff).

Rollback to previous revision:

helm rollback my-nginx 1   # or 2, 3... (check with helm history my-nginx)

→ Back to working state instantly.

Step 6: Cleanup¶

Uninstall the chart:

helm uninstall my-nginx

→ Deletes all resources created by the chart (Deployment, Service, etc.)

Key Takeaways¶

• Helm = templated, reusable YAML + one-command install/upgrade/rollback
• Charts = pre-packaged apps (bitnami/nginx, bitnami/postgresql, wordpress, etc.)
• values.yaml = your customizations (replicas, images, config, ingress…)
• helm repo + search → discover charts
• Production: Use Helmfile, Helmfile + GitOps, or ChartMuseum for private charts

This is a game-changer for managing complexity, most advanced Kubernetes users rely on Helm daily.

→ Next: Part 3 – Resource Limits, Requests & Horizontal Pod Autoscaler (HPA)