Learn more about the kafka-topics tool.

Use the kafka-topics tool to generate a snapshot of topics in the Kafka cluster.

kafka-topics --bootstrap-server [BROKER_HOST]:[PORT] --describe
Topic: topic-a1      PartitionCount:3      ReplicationFactor:3      Configs:
         Topic: topic-a1      Partition: 0      Leader: 64      Replicas: 64,62,63      Isr: 64,62,63
         Topic: topic-a1      Partition: 1      Leader: 62      Replicas: 62,63,64      Isr: 62,63,64
         Topic: topic-a1      Partition: 2      Leader: 63      Replicas: 63,64,62      Isr: 63,64,62
Topic: topic-a2      PartitionCount:1      ReplicationFactor:3      Configs:
         Topic: topic-a2      Partition: 0      Leader: 64      Replicas: 64,62,63      Isr: 64,62,63

The output lists each topic and basic partition information. Note the following about the output:

  • Partition count: The more partitions, the higher the possible parallelism among consumers and producers.
  • Replication factor: Shows 1 for no redundancy and higher for more redundancy.
  • Replicas and in-sync replicas (ISR): Shows which broker ID’s have the partitions and which replicas are current.

There are situations where this tool shows an invalid value for the leader broker ID or the number of ISRs is fewer than the number of replicas. In those cases, there may be something wrong with those specific topics.

It is possible to change topic configuration properties using this tool. Increasing the partition count, the replication factor or both is not recommended.