A Deep Dive into Kafka Commands: From Beginner to Expert

Detailed explanation of Kafka commands: from beginner to master

1. Introduction

Apache Kafka is a distributed publish-subscribe messaging system that allows you to Send and receive messages with high throughput and low latency. Kafka is widely used to build real-time data pipelines, microservice architectures, and streaming applications.

2. Basic commands

2.1 Create topic

kafka-topics --create --topic test-topic --partitions 3 --replication-factor 2

This command will create a topic named test-topic, which has 3 Partition and 2 replicas.

2.2 List topics

kafka-topics --list

This command will list all available topics.

2.3 View topic details

kafka-topics --describe --topic test-topic

This command will display detailed information about the test-topic topic, including partitions, replicas, and message retention policies.

2.4 Production Messages

kafka-console-producer --topic test-topic

This command will start an interactive console that allows you to send messages to the test-topic topic.

2.5 Consuming Messages

kafka-console-consumer --topic test-topic --from-beginning

This command will launch an interactive console that allows you to consume messages from the test-topic topic.

3. Advanced commands

3.1 Change the number of topic partitions

kafka-topics --alter --topic test-topic --partitions 5

This command will increase the number of partitions of the test-topic topic to 5.

3.2 Change the number of topic replicas

kafka-topics --alter --topic test-topic --replication-factor 3

This command will increase the number of replicas of the test-topic topic to 3.

3.3 Set topic message retention policy

kafka-topics --alter --topic test-topic --config retention.ms=60000

This command will set the message retention time of the test-topic topic to 60 seconds.

3.4 Create a consumer group

kafka-consumer-groups --create --group test-group

This command will create a consumer group named test-group.

3.5 List consumer groups

kafka-consumer-groups --list

This command will list all available consumer groups.

3.6 View consumer group details

kafka-consumer-groups --describe --group test-group

This command will display detailed information about the test-groupconsumer group, including members, offset and consumption speed .

4. Troubleshooting

4.1 The topic does not exist

If you receive the Unknown topic or partition error, it means that the topic does not exist. You can create a topic using the kafka-topics --create command.

4.2 The partition does not exist

If you receive the Unknown partition error, it means that the partition does not exist. You can use the kafka-topics --alter command to change the number of partitions for a topic.

4.3 The number of replicas is incorrect

If you receive the Replication factor out of range error, it means that the number of replicas for the topic is incorrect. You can change the number of replicas of a topic using the kafka-topics --alter command.

4.4 The message retention time is incorrect

If you receive the Retention time out of range error, it means that the message retention time for the topic is incorrect. You can change the message retention time of a topic using the kafka-topics --alter command.

5. Summary

Kafka is a powerful distributed publish-subscribe messaging system that can be used to build real-time data pipelines, microservice architectures, and streaming applications. This article explains some basic and advanced commands of Kafka and how to troubleshoot common problems.

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