Kafka useful commands on Macbook or linux

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  • Start up the Zookeeper.
./zookeeper-server-start.sh ../config/zookeeper.properties
  • Add the below properties in the server.properties
listeners=PLAINTEXT://localhost:9092auto.create.topics.enable=false
  • Start up the Kafka Broker
./kafka-server-start.sh ../config/server.properties

How to create a topic ?

./kafka-topics.sh –create –topic test-topic –bootstrap-server localhost:9092 –replication-factor 1 –partitions 4

Output: Created topic test-topic.

Describe Topic command

./kafka-topics.sh –describe –topic test-topic –bootstrap-server localhost:9092

output:

Topic: test-topic TopicId: O-uBj0D_R6aMhKMsTUgqhg PartitionCount: 4 ReplicationFactor: 1 Configs: segment.bytes=1073741824

Topic: test-topic. Partition: 0   Leader: 0. Replicas: 0. Isr:   0

Topic: test-topic. Partition: 1. Leader: 0. Replicas: 0. Isr:   0

Topic: test-topic. Partition: 2. Leader: 0. Replicas: 0. Isr:   0

Topic: test-topic. Partition: 3. Leader: 0. Replicas: 0. Isr:   0

How to instantiate a Console Producer?

Without Key

./kafka-console-producer.sh --broker-list localhost:9092 --topic test-topic

With Key

./kafka-console-producer.sh --broker-list localhost:9092 --topic test-topic --property "key.separator=-" --property "parse.key=true"

How to instantiate a Console Consumer?

Without Key

./kafka-console-consumer.sh --bootstrap-server localhost:9092 --topic test-topic --from-beginning

With Key

./kafka-console-consumer.sh --bootstrap-server localhost:9092 --topic test-topic --from-beginning -property "key.separator= - " --property "print.key=true"

With Consumer Group

./kafka-console-consumer.sh --bootstrap-server localhost:9092 --topic test-topic --group <group-name>

To list down all topics

./kafka-topics.sh –bootstrap-server localhost:9092 –list

To know consumer groups:

./kafka-consumer-groups.sh –bootstrap-server localhost:9092 –list

List the topics in a cluster

./kafka-topics.sh --bootstrap-server localhost:9092 --list

Describe topic

  • The below command can be used to describe all the topics.
./kafka-topics.sh --bootstrap-server localhost:9092 --describe
  • The below command can be used to describe a specific topic.
./kafka-topics.sh --bootstrap-server localhost:9092 --describe --topic <topic-name>

Alter the min insync replica

./kafka-configs.sh  --bootstrap-server localhost:9092 --entity-type topics --entity-name library-events --alter --add-config min.insync.replicas=2

Delete a topic

./kafka-topics.sh --bootstrap-server localhost:9092 --delete --topic test-topic

How to view consumer groups

./kafka-consumer-groups.sh --bootstrap-server localhost:9092 --list

Consumer Groups and their Offset

./kafka-consumer-groups.sh --bootstrap-server localhost:9092 --describe --group console-consumer-27773

Viewing the Commit Log

./kafka-run-class.sh kafka.tools.DumpLogSegments --deep-iteration --files /tmp/kafka-logs/test-topic-0/00000000000000000000.log

Setting the Minimum Insync Replica

./kafka-configs.sh --alter --bootstrap-server localhost:9092 --entity-type topics --entity-name test-topic --add-config min.insync.replicas=2

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