kafka-util

Kafka utilities meant to supplement existing tools such as kafka-topics.sh, kafka-reassign-partitions.sh, and kafka-leader-election.sh.

Kafka bootstrap server

A Kafka bootstrap server needs to be passed in either with the --bootstrap-server flag or the KAFKA_BOOTSTRAP_SERVER environment variable.

Ongoing reassignments

To list ongoing reassignments:

kafka-util ongoing

To cancel any ongoing reassignments:

kafka-util ongoing --cancel

To wait for any ongoing reassignments to complete:

kafka-util ongoing --wait

Reassign a single partition

To set the replica set of partition 0 of topic foobar to {0, 1, 2}:

kafka-util reassign -t foobar -p 0 -r 0,1,2

Do the above, but wait for the reassignment to complete before returning:

kafka-util reassign -t foobar -p 0 -r 0,1,2 && kafka-util ongoing --wait

Reassign multiple partitions with a per-broker concurrency limit

The stage subcommand executes a series of partition reassignments.

The partition reassignments are given as a JSON file in the same format that the kafka-reassign-partitions.sh utility generates:

{
  "partitions": [
    {
      "topic": "foo",
      "partition": 1,
      "replicas": [1,2,3],
      "log_dirs": ["dir1", "dir2", "dir3"]
    }
  ],
  "version": 1
}

The --max-moves-per-broker flag specifies the maximum number of simultaneous inter-broker replica movements allowed per broker. A broker is considered part of a replica movement if it is either the source or destination broker of the replica or is the lead replica of the partition.

To execute a manual assignment json file with a concurrency limit of 1:

kafka-util stage --reassignment-json-file reassignments.json --max-moves-per-broker 1

Use the --dry-run flag to print the reassignments without actually executing them:

kafka-util stage --reassignment-json-file reassignments.json --max-moves-per-broker 1 --dry-run

Describe topics

To describe topics:

kafka-util topics --topic foobar --topic foobaz

To print partition leadership distribution per topic:

kafka-util topics --topic foobar --topic foobaz --leader-distribution

To print partition replica distribution per topic:

kafka-util topics --topic foobar --topic foobaz --replica-distribution

Generate a topics-to-move JSON file:

kafka-util topics --topic foobar --topic foobaz --generate