Describe the process of upgrading a Kafka cluster to a newer version with examples

Category : Apache Kafka | Sub Category : Apache Kafka | By Prasad Bonam Last updated: 2023-08-05 11:15:09 Viewed : 312

Describe the process of upgrading a Kafka cluster to a newer version with examples:

Upgrading a Kafka cluster to a newer version should be done with careful planning and consideration for backward compatibility and potential impact on the existing applications and consumers. Here is a step-by-step process to upgrade a Kafka cluster to a newer version, along with examples:

Step 1: Read the Release Notes

• Start by reading the release notes of the new Kafka version you plan to upgrade to. The release notes will provide information about new features, bug fixes, and any breaking changes that might affect your existing setup.

Step 2: Test the Upgrade in a Non-Production Environment

• Before upgrading the production cluster, perform a test upgrade in a non-production environment, such as a staging or development cluster. This step will help identify any potential issues specific to your setup.

Step 3: Backup Data and Configurations

• Take a complete backup of the data and configurations of the existing Kafka cluster. This is a precautionary step to ensure data safety during the upgrade process.

Step 4: Upgrade ZooKeeper (If Needed)

• If the new Kafka version requires a different version of Apache ZooKeeper, upgrade ZooKeeper first. Kafka relies on ZooKeeper for coordination, so make sure ZooKeeper is compatible with the new Kafka version.

Step 5: Upgrade Kafka Brokers

• Upgrade the Kafka brokers one by one. For a smooth upgrade, you can add new brokers running the new Kafka version to the cluster while keeping the old brokers running.
• Use a rolling upgrade approach to minimize downtime. Take one broker offline, upgrade it to the new version, and bring it back online before proceeding to the next broker.

Example: Rolling Upgrade Using Docker Compose Suppose you have a Docker Compose setup for your Kafka cluster. To upgrade a single Kafka broker to version 2.8.0:

1. Modify your Docker Compose file to use the new Kafka image version:

yamlCopy code
services:
  kafka1:
    image: wurstmeister/kafka:2.8.0
    container_name: kafka1
    ports:
      - "9092:9092"
    environment:
      KAFKA_ADVERTISED_LISTENERS: INSIDE://kafka1:9092,OUTSIDE://localhost:9092
      KAFKA_LISTENER_SECURITY_PROTOCOL_MAP: INSIDE:PLAINTEXT,OUTSIDE:PLAINTEXT
      KAFKA_LISTENERS: INSIDE://0.0.0.0:9092,OUTSIDE://0.0.0.0:9092
      KAFKA_INTER_BROKER_LISTENER_NAME: INSIDE
      KAFKA_BROKER_ID: 1
      KAFKA_LOG_DIRS: /kafka/kafka-logs-1
      KAFKA_AUTO_CREATE_TOPICS_ENABLE: "false"
    volumes:
      - /var/run/docker.sock:/var/run/docker.sock
      - ./data/kafka1:/kafka
    depends_on:
      - zookeeper

2. Stop the Kafka1 container:

bashCopy code
docker-compose stop kafka1

3. Remove the Kafka1 container (optional, but it is a good practice to remove the old container and ensure a clean state):

bashCopy code
docker-compose rm kafka1

4. Start the upgraded Kafka1 container:

bashCopy code
docker-compose up -d kafka1

Step 6: Validate the Upgrade

• After upgrading all Kafka brokers, validate the new Kafka version by testing the functionality and performance of your Kafka cluster in the non-production environment.

Step 7: Update Client Applications

• Update the client applications (producers and consumers) to use the new Kafka client libraries compatible with the upgraded Kafka version.

Step 8: Upgrade the Production Cluster

• Once the upgrade is thoroughly tested in the non-production environment and client applications are updated, follow a similar rolling upgrade process to upgrade the production Kafka cluster.

Step 9: Monitor and Verify

• Monitor the production Kafka cluster closely after the upgrade to ensure that everything is working as expected. Verify that consumers are able to consume messages correctly, and producers can send messages without issues.

Step 10: Complete the Upgrade

• Once you are satisfied that the production Kafka cluster is running smoothly with the new version, complete the upgrade by decommissioning the old Kafka brokers if necessary.

Remember to test and plan the upgrade carefully to minimize any potential disruption to your Kafka-based applications and data processing pipelines.