An open-source project by

This project is sponsored by Conduktor.io, a graphical desktop user interface for Apache Kafka.

Once you have started your cluster, you can use Conduktor to easily manage it. Just connect against localhost:9092. If you are on Mac or Windows and want to connect from another container, use host.docker.internal:29092

kafka-stack-docker-compose

This replicates as well as possible real deployment configurations, where you have your zookeeper servers and kafka servers actually all distinct from each other. This solves all the networking hurdles that comes with Docker and docker compose, and is compatible cross platform.

UPDATE: No /etc/hosts file changes are necessary anymore. Explanations at: https://rmoff.net/2018/08/02/kafka-listeners-explained/

Stack version

• Conduktor Platform: latest
• Zookeeper version: 3.6.3 (Confluent 7.3.2)
• Kafka version: 3.3.0 (Confluent 7.3.2)
• Kafka Schema Registry: Confluent 7.3.2
• Kafka Rest Proxy: Confluent 7.3.2
• Kafka Connect: Confluent 7.3.2
• ksqlDB Server: Confluent 7.3.2
• Zoonavigator: 1.1.1

For a UI tool to access your local Kafka cluster, use the free version of Conduktor

Requirements

Kafka will be exposed on 127.0.0.1 or DOCKER_HOST_IP if set in the environment. (You probably don't need to set it if you're not using Docker-Toolbox)

Docker-Toolbox

Docker toolbox is deprecated and not maintained anymore for several years. We can't guarantee this stack will work with Docker Toolbox, but if you want to try anyway, please export your environment before starting the stack:

export DOCKER_HOST_IP=192.168.99.100

(your docker machine IP is usually 192.168.99.100)

Apple M1 support

Confluent platform supports Apple M1 (ARM64) since version 7.2.0! Basically, this stack will work out of the box.

If you want to downgrade confluent platform version, there are two ways:

1. Add platform: linux/amd64. It will work as docker is able to emulate AMD64 instructions.
2. Previous versions have been built for ARM64 by the community. If you want to use it, just change the image in the corresponding yml. Since it is a not an official image, use it at your own risks.

Full stack

To ease you journey with kafka just connect to localhost:8080

login: [email protected] password: admin

• Conduktor-platform: $DOCKER_HOST_IP:8080
• Single Zookeeper: $DOCKER_HOST_IP:2181
• Single Kafka: $DOCKER_HOST_IP:9092
• Kafka Schema Registry: $DOCKER_HOST_IP:8081
• Kafka Rest Proxy: $DOCKER_HOST_IP:8082
• Kafka Connect: $DOCKER_HOST_IP:8083
• KSQL Server: $DOCKER_HOST_IP:8088
• (experimental) JMX port at $DOCKER_HOST_IP:9001

Run with:

docker compose -f full-stack.yml up
docker compose -f full-stack.yml down

** Note: if you find that you can not connect to localhost:8080 please run docker compose -f full-stack.yml build to rebuild the port mappings.

Single Zookeeper / Single Kafka

This configuration fits most development requirements.

• Zookeeper will be available at $DOCKER_HOST_IP:2181
• Kafka will be available at $DOCKER_HOST_IP:9092
• (experimental) JMX port at $DOCKER_HOST_IP:9999

Run with:

docker compose -f zk-single-kafka-single.yml up
docker compose -f zk-single-kafka-single.yml down

Single Zookeeper / Multiple Kafka

If you want to have three brokers and experiment with kafka replication / fault-tolerance.

• Zookeeper will be available at $DOCKER_HOST_IP:2181
• Kafka will be available at $DOCKER_HOST_IP:9092,$DOCKER_HOST_IP:9093,$DOCKER_HOST_IP:9094

Run with:

docker compose -f zk-single-kafka-multiple.yml up
docker compose -f zk-single-kafka-multiple.yml down

Multiple Zookeeper / Single Kafka

If you want to have three zookeeper nodes and experiment with zookeeper fault-tolerance.

• Zookeeper will be available at $DOCKER_HOST_IP:2181,$DOCKER_HOST_IP:2182,$DOCKER_HOST_IP:2183
• Kafka will be available at $DOCKER_HOST_IP:9092
• (experimental) JMX port at $DOCKER_HOST_IP:9999

Run with:

docker compose -f zk-multiple-kafka-single.yml up
docker compose -f zk-multiple-kafka-single.yml down

Multiple Zookeeper / Multiple Kafka

If you want to have three zookeeper nodes and three kafka brokers to experiment with production setup.

• Zookeeper will be available at $DOCKER_HOST_IP:2181,$DOCKER_HOST_IP:2182,$DOCKER_HOST_IP:2183
• Kafka will be available at $DOCKER_HOST_IP:9092,$DOCKER_HOST_IP:9093,$DOCKER_HOST_IP:9094

Run with:

docker compose -f zk-multiple-kafka-multiple.yml up
docker compose -f zk-multiple-kafka-multiple.yml down

FAQ

Kafka

Q: Kafka's log is too verbose, how can I reduce it?

A: Add the following line to your docker compose environment variables: KAFKA_LOG4J_LOGGERS: "kafka.controller=INFO,kafka.producer.async.DefaultEventHandler=INFO,state.change.logger=INFO". Full logging control can be accessed here: https://github.com/confluentinc/cp-docker-images/blob/master/debian/kafka/include/etc/confluent/docker/log4j.properties.template

Q: How do I delete data to start fresh?

A: Your data is persisted from within the docker compose folder, so if you want for example to reset the data in the full-stack docker compose, do a docker compose -f full-stack.yml down.

Q: Can I change the zookeeper ports?

A: yes. Say you want to change zoo1 port to 12181 (only relevant lines are shown):

  zoo1:
    ports:
      - "12181:12181"
    environment:
        ZOO_PORT: 12181
        
  kafka1:
    environment:
      KAFKA_ZOOKEEPER_CONNECT: "zoo1:12181"

Q: Can I change the Kafka ports?

A: yes. Say you want to change kafka1 port to 12345 (only relevant lines are shown). Note only LISTENER_DOCKER_EXTERNAL changes:

  kafka1:
    image: confluentinc/cp-kafka:7.2.1
    hostname: kafka1
    ports:
      - "12345:12345"
    environment:
      KAFKA_ADVERTISED_LISTENERS: INTERNAL://kafka1:19092,EXTERNAL://${DOCKER_HOST_IP:-127.0.0.1}:12345,DOCKER://host.docker.internal:29092

Q: Kafka is using a lot of disk space for testing. Can I reduce it?

A: yes. This is for testing only!!! Reduce the KAFKA_LOG_SEGMENT_BYTES to 16MB and the KAFKA_LOG_RETENTION_BYTES to 128MB

  kafka1:
    image: confluentinc/cp-kafka:7.2.1
    ...
    environment:
      ...
      # For testing small segments 16MB and retention of 128MB
      KAFKA_LOG_SEGMENT_BYTES: 16777216
      KAFKA_LOG_RETENTION_BYTES: 134217728

Q: How do I expose kafka?

A: If you want to expose kafka outside of your local machine, you must set KAFKA_ADVERTISED_LISTENERS to the IP of the machine so that kafka is externally accessible. To achieve this you can set LISTENER_DOCKER_EXTERNAL to the IP of the machine. For example, if the IP of your machine is 50.10.2.3, follow the sample mapping below:

  kafka1:
    image: confluentinc/cp-kafka:7.2.1
    ...
    environment:
      ...
      KAFKA_ADVERTISED_LISTENERS: INTERNAL://kafka2:19093,EXTERNAL://50.10.2.3:9093,DOCKER://host.docker.internal:29093

Q: How do I add connectors to kafka connect?

Create a connectors directory and place your connectors there (usually in a subdirectory) connectors/example/my.jar

The directory is automatically mounted by the kafka-connect Docker container

OR edit the bash command which pulls connectors at runtime

confluent-hub install --no-prompt debezium/debezium-connector-mysql:latest
        confluent-hub install 

Q: How to disable Confluent metrics?

Add this environment variable

KAFKA_CONFLUENT_SUPPORT_METRICS_ENABLE=false