Helm charts concept in Kubernetes - Mini Project: Build & Apply

Deploy a Simple Web App Using Helm Charts

📖 Scenario: You are working as a DevOps engineer. Your team wants to deploy a simple web application on Kubernetes. To make deployment easier and reusable, you will use Helm charts. Helm helps package Kubernetes resources together.

🎯 Goal: Build a Helm chart for a simple web app that runs an NGINX server. You will create the chart, configure values, write templates, and deploy using Helm commands.

📋 What You'll Learn

Create a Helm chart using the helm create command

Configure values.yaml with app name, image, and replica count

Understand the generated deployment and service templates

Deploy the Helm chart and verify the app is running

💡 Why This Matters

🌍 Real World

Helm charts are widely used to package and deploy applications on Kubernetes clusters. They simplify managing complex Kubernetes manifests and enable easy upgrades and rollbacks.

💼 Career

Knowing Helm is essential for DevOps engineers working with Kubernetes. It helps automate deployments, manage configurations, and maintain consistency across environments.

1

Create a Helm chart using helm create

Use the helm create command to scaffold a new Helm chart named mywebapp. This generates the standard chart directory structure with Chart.yaml, values.yaml, and templates.

Kubernetes

# Create a new Helm chart
# Your code here

Hint

Use helm create mywebapp to generate the full chart structure automatically.

2

Configure values.yaml with app settings

Edit the values.yaml file inside the mywebapp chart. Set the image repository to nginx, image tag to stable, and replica count to 2.

Kubernetes

helm create mywebapp

# Edit mywebapp/values.yaml with image and replica settings
# Your code here

Hint

Use cat < mywebapp/values.yaml to write the values file with replicaCount, image repository, and tag.

3

Install the Helm chart to deploy the app

Use helm install to deploy the chart. Name the release mywebapp-release and point to the mywebapp chart directory.

Kubernetes

helm create mywebapp

cat  mywebapp/values.yaml
replicaCount: 2

image:
  repository: nginx
  tag: stable
  pullPolicy: IfNotPresent

service:
  type: ClusterIP
  port: 80
EOF

# Deploy the chart using helm install
# Your code here

Hint

Use helm install mywebapp-release ./mywebapp to deploy the chart from the local directory.

4

Verify the deployment is running

Use kubectl get pods and kubectl get svc to verify the pods and service are created. Then print Helm deployment successful to confirm.

Kubernetes

helm create mywebapp

cat  mywebapp/values.yaml
replicaCount: 2

image:
  repository: nginx
  tag: stable
  pullPolicy: IfNotPresent

service:
  type: ClusterIP
  port: 80
EOF

helm install mywebapp-release ./mywebapp

# Verify deployment and print confirmation
# Your code here

Hint

Use kubectl get pods and kubectl get svc to check, then echo 'Helm deployment successful'.

Practice

1. What is the primary purpose of a Helm chart in Kubernetes?

easy

A. To replace kubectl commands

B. To monitor Kubernetes cluster health

C. To package and deploy Kubernetes applications easily

D. To create Docker images

Solution

1. Step 1: Understand Helm chart role

   A Helm chart bundles Kubernetes app resources for easy deployment and sharing.

2. Step 2: Compare options

   Options B, C, and D describe other tools or tasks unrelated to Helm charts.

3. Final Answer:

   To package and deploy Kubernetes applications easily -> Option C

4. Quick Check:

   Helm chart = package & deploy app [OK]

Hint: Helm charts bundle apps for easy deployment [OK]

Common Mistakes:

• Confusing Helm with monitoring tools
• Thinking Helm replaces kubectl entirely
• Assuming Helm builds Docker images

2. Which Helm command is used to create a new chart skeleton?

easy

A. helm rollback

B. helm install

C. helm upgrade

D. helm create

Solution

1. Step 1: Identify command purpose

   helm create generates a new chart directory with default files.

2. Step 2: Eliminate other commands

   helm install deploys charts, helm upgrade updates releases, helm rollback reverts upgrades.

3. Final Answer:

   helm create -> Option D

4. Quick Check:

   New chart skeleton = helm create [OK]

Hint: Use helm create to start a chart [OK]

Common Mistakes:

• Using helm install to create charts
• Confusing upgrade with create
• Trying rollback to create charts

3. Given the command helm install myapp ./mychart, what happens?

medium

A. Installs the release 'myapp' using the chart from the local directory './mychart'

B. Creates a new chart named 'myapp' in './mychart'

C. Upgrades the release 'myapp' with './mychart'

D. Rolls back the release 'myapp' to './mychart'

Solution

1. Step 1: Understand helm install syntax

   helm install [release-name] [chart-path] deploys the chart as a release.

2. Step 2: Analyze given command

   Here, 'myapp' is the release name, './mychart' is the chart directory to deploy.

3. Final Answer:

   Installs the release 'myapp' using the chart from the local directory './mychart' -> Option A

4. Quick Check:

   helm install = deploy chart [OK]

Hint: helm install deploys chart as release [OK]

Common Mistakes:

• Thinking install creates charts
• Confusing install with upgrade or rollback
• Misunderstanding release name vs chart path

4. You run helm upgrade myapp ./mychart but get an error: "release: not found". What is the likely cause?

medium

A. The release 'myapp' does not exist yet

B. The chart path './mychart' is invalid

C. You need to use helm install instead of upgrade

D. The Kubernetes cluster is down

Solution

1. Step 1: Understand helm upgrade error

   The error "release: not found" means the named release does not exist in the cluster.

2. Step 2: Identify correct cause

   Since upgrade updates existing releases, trying to upgrade a non-existent release causes this error.

3. Final Answer:

   The release 'myapp' does not exist yet -> Option A

4. Quick Check:

   Upgrade needs existing release [OK]

Hint: Upgrade fails if release not installed yet [OK]

Common Mistakes:

• Assuming chart path error causes this message
• Using upgrade instead of install for new release
• Blaming cluster status without checking release

5. You want to deploy a Helm chart and be able to easily revert to the previous version if needed. Which Helm commands should you use in order?

hard

A. helm create, helm install, helm rollback

B. helm install, helm upgrade, helm rollback

C. helm create, helm upgrade, helm rollback

D. helm install, helm create, helm rollback

Solution

1. Step 1: Understand deployment and version control

   First, use helm install to deploy the initial release.

2. Step 2: Manage updates and rollback

   Use helm upgrade to update the release, and helm rollback to revert if needed.

3. Step 3: Eliminate incorrect sequences

   helm create is for making charts, not deployment steps. It should not be in the deploy/rollback sequence.

4. Final Answer:

   helm install, helm upgrade, helm rollback -> Option B

5. Quick Check:

   Install -> Upgrade -> Rollback = C [OK]

Hint: Install first, then upgrade, rollback if needed [OK]

Common Mistakes:

• Using helm create in deployment sequence
• Skipping install before upgrade
• Confusing rollback with create