Helm charts for Kafka - Mini Project: Build & Apply

Deploy Kafka using Helm Charts

📖 Scenario: You are setting up a Kafka messaging system on Kubernetes. Using Helm charts makes it easy to install and manage Kafka clusters.

🎯 Goal: Learn how to deploy a Kafka cluster on Kubernetes using Helm charts step-by-step.

📋 What You'll Learn

Install Helm on your local machine

Have access to a Kubernetes cluster

Use the Bitnami Kafka Helm chart repository

💡 Why This Matters

🌍 Real World

Helm charts simplify deploying complex applications like Kafka on Kubernetes clusters, saving time and reducing errors.

💼 Career

Knowing how to deploy Kafka with Helm is valuable for DevOps engineers, site reliability engineers, and backend developers working with event streaming.

1

Add the Bitnami Helm repository

Run the command helm repo add bitnami https://charts.bitnami.com/bitnami to add the Bitnami Helm chart repository.

Kafka

# Run the command to add the Bitnami Helm repo
# Your code here

Hint

This command tells Helm where to find the Kafka charts.

2

Update Helm repositories

Run the command helm repo update to refresh the Helm chart information from all repositories.

Kafka

helm repo add bitnami https://charts.bitnami.com/bitnami
# Run the command to update Helm repos
# Your code here

Hint

This command downloads the latest chart info so you can install the newest Kafka version.

3

Install Kafka using Helm

Run the command helm install my-kafka bitnami/kafka to install Kafka with the release name my-kafka.

Kafka

helm repo add bitnami https://charts.bitnami.com/bitnami
helm repo update
# Run the command to install Kafka with release name my-kafka
# Your code here

Hint

This command deploys Kafka on your Kubernetes cluster using Helm.

4

Check Kafka pods status

Run the command kubectl get pods -l app.kubernetes.io/name=kafka to see the Kafka pods running in your cluster.

Kafka

helm repo add bitnami https://charts.bitnami.com/bitnami
helm repo update
helm install my-kafka bitnami/kafka
# Run the command to list Kafka pods
# Your code here

Hint

This command shows the status of Kafka pods to confirm the deployment.

Practice

1. What is the main purpose of using Helm charts for Kafka deployment on Kubernetes?

easy

A. To automate and simplify Kafka deployment and management

B. To write Kafka application code

C. To monitor Kafka topics manually

D. To replace Kafka brokers with databases

Solution

1. Step 1: Understand Helm charts role

   Helm charts package Kubernetes resources to automate deployment and management.

2. Step 2: Apply to Kafka context

   Using Helm charts for Kafka automates its deployment and configuration on Kubernetes clusters.

3. Final Answer:

   To automate and simplify Kafka deployment and management -> Option A

4. Quick Check:

   Helm automates Kafka deployment = B [OK]

Hint: Helm automates deployment tasks for Kafka on Kubernetes [OK]

Common Mistakes:

• Confusing Helm with Kafka application coding
• Thinking Helm replaces Kafka brokers
• Assuming Helm is for manual monitoring

2. Which Helm command syntax correctly sets the Kafka broker count to 3 during installation?

easy

A. helm install kafka bitnami/kafka --set brokerCount=3

B. helm install kafka bitnami/kafka --set brokers=3

C. helm install kafka bitnami/kafka --set replicaCount=3

D. helm install kafka bitnami/kafka --set kafka.broker=3

Solution

1. Step 1: Identify correct Helm parameter for replicas

   Common Helm charts use replicaCount to set number of pods/brokers.

2. Step 2: Match parameter with Kafka Helm chart

   Bitnami Kafka chart uses replicaCount to define broker count.

3. Final Answer:

   helm install kafka bitnami/kafka --set replicaCount=3 -> Option C

4. Quick Check:

   replicaCount sets broker pods = A [OK]

Hint: Use replicaCount to set broker number in Helm [OK]

Common Mistakes:

• Using incorrect parameter names like brokers or brokerCount
• Misplacing dot notation in --set
• Confusing Helm install syntax

3. Given this Helm command:

helm install kafka bitnami/kafka --set replicaCount=2,logRetentionHours=168

What will be the effect on the Kafka deployment?

medium

A. Deploy 2 Kafka brokers with logs retained for 168 hours

B. Deploy 168 Kafka brokers with 2 hours log retention

C. Deploy 2 Kafka brokers with default log retention

D. Deployment will fail due to syntax error

Solution

1. Step 1: Analyze replicaCount setting

   replicaCount=2 means 2 Kafka broker pods will be deployed.

2. Step 2: Analyze logRetentionHours setting

   logRetentionHours=168 sets log retention to 168 hours (7 days).

3. Final Answer:

   Deploy 2 Kafka brokers with logs retained for 168 hours -> Option A

4. Quick Check:

   replicaCount=2 and logRetentionHours=168 = D [OK]

Hint: Check each --set key=value carefully for effect [OK]

Common Mistakes:

• Mixing up values of replicaCount and logRetentionHours
• Assuming syntax error due to comma
• Ignoring log retention setting

4. You run this Helm upgrade command:

helm upgrade kafka bitnami/kafka --set replicaCount=3

But the Kafka deployment still has 2 brokers. What is the likely issue?

medium

A. The Helm chart version is incompatible

B. The Helm release name is incorrect

C. Kafka does not support scaling brokers via Helm

D. The replicaCount value was not applied due to missing --reuse-values flag

Solution

1. Step 1: Understand Helm upgrade behavior

   Helm upgrade requires --reuse-values to reuse previous values while applying new --set overrides.

2. Step 2: Identify why replicaCount didn't change

   Without --reuse-values, the new value may not apply correctly in combination with prior settings.

3. Final Answer:

   The replicaCount value was not applied due to missing --reuse-values flag -> Option D

4. Quick Check:

   Missing --reuse-values can block value changes = A [OK]

Hint: Use --reuse-values to keep and update Helm settings on upgrade [OK]

Common Mistakes:

• Assuming Helm release name is wrong
• Believing Kafka can't scale brokers
• Ignoring Helm chart version compatibility

5. You want to deploy Kafka with 3 brokers and customize the storage size to 50Gi using Helm. Which command correctly achieves this?

hard

A. helm install kafka bitnami/kafka --set replicaCount=3,storage.size=50Gi

B. helm install kafka bitnami/kafka --set replicaCount=3 --set persistence.size=50Gi

C. helm install kafka bitnami/kafka --set brokers=3 --set storage.size=50Gi

D. helm install kafka bitnami/kafka --set replicaCount=3 --set persistence.storage=50Gi

Solution

1. Step 1: Set broker count correctly

   replicaCount=3 sets 3 Kafka brokers.

2. Step 2: Set storage size correctly

   Bitnami Kafka chart uses persistence.size to define storage size per broker.

3. Step 3: Use correct Helm syntax

   Separate --set flags or comma-separated values are valid, but helm install kafka bitnami/kafka --set replicaCount=3 --set persistence.size=50Gi uses clear separate flags.

4. Final Answer:

   helm install kafka bitnami/kafka --set replicaCount=3 --set persistence.size=50Gi -> Option B

5. Quick Check:

   replicaCount and persistence.size set correctly = C [OK]

Hint: Use replicaCount and persistence.size keys for brokers and storage [OK]

Common Mistakes:

• Using wrong keys like brokers or storage.size
• Combining keys incorrectly in one --set
• Using persistence.storage instead of persistence.size