Steady state rebalancing for Amazon MSK clusters - Amazon Managed Streaming for Apache Kafka
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Steady state rebalancing for Amazon MSK clusters

Note

Effective June 18, 2026, Intelligent Rebalancing is available for all MSK Provisioned clusters with Express brokers. This includes Express clusters created prior to the launch of intelligent rebalancing feature in November 2025. For clusters created before November 20, 2025, Intelligent Rebalancing is available with Rebalancing Status set to Paused. To enable this feature for your existing clusters, set Rebalancing Status to Active using the Amazon MSK console, AWS CLI, or SDK. For instructions, see Steady state rebalancing.

Steady state rebalancing is a part of the intelligent rebalancing feature, which is turned on by default for all new MSK Provisioned clusters with Express brokers. As you scale your clusters up or down, Amazon MSK automatically handles partition management by distributing partitions to new brokers and moving partitions from brokers due for removal. To ensure optimal distribution of workload across brokers, intelligent rebalancing uses Amazon MSK best practices to determine thresholds for automatically initiating rebalancing for your brokers.

You can pause and resume steady state rebalancing when needed. Steady state rebalancing continuously monitors your cluster and does the following:

  • Tracks broker resource usage (CPU, network, storage).

  • Adjusts partition placement automatically without any impact on data availability.

  • Completes rebalancing operations up to 180x faster for Express brokers as compared to Standard brokers.

  • Maintains cluster performance.

Topics
    Pause and resume steady state rebalancing in AWS Management Console

    1. Open the Amazon MSK console at https://eusc-de-east-1.console.amazonaws-eusc.eu/msk/home?region=us-east-1#/home/.

    2. On the Clusters page, choose an Express-based cluster. For information about creating a provisioned Express-based cluster, see Step 1: Create an MSK Provisioned cluster.

    3. On the Cluster detail page, verify the Intelligent rebalancing status. If the status is Paused, follow steps 4–5 to enable it.

    4. On the Actions dropdown list, choose Edit intelligent rebalancing.

    5. On the Edit intelligent rebalancing page, do the following:

      1. Choose Active.

      2. Choose Save changes.

    Pause and resume steady state rebalancing using AWS CLI

    To set the rebalancing status of a cluster to ACTIVE using the AWS CLI, use the update-rebalancing command, as shown in the following example. In this command, specify the status with the rebalancing parameter.

    aws msk update-rebalancing --cluster-arn arn:aws-eusc:kafka:eusc-de-east-1:123456789012:cluster/myCluster/abcd1234-5678-90ef-ghij-klmnopqrstuv-1 --current-version ABCDEF1GHIJK0L --rebalancing "{\"Rebalancing\":{\"Status\":\"ACTIVE\"}}"
    Pause and resume steady state rebalancing using AWS SDK

    You can also set the rebalancing status of a cluster using the UpdateRebalancingRequest API to programmatically modify the broker count. The following examples show how to set the rebalancing status to ACTIVE and PAUSED.

    final UpdateRebalancingRequest updateRebalancingRequest = new UpdateRebalancingRequest()
    .withClusterArn(arn:aws-eusc:kafka:eusc-de-east-1:123456789012:cluster/myCluster/abcd1234-5678-90ef-ghij-klmnopqrstuv-1)
    .withCurrentVersion(ABCDEF1GHIJK0L)
    .withRebalancing(new Rebalancing().withStatus("ACTIVE"));
    final UpdateRebalancingRequest updateRebalancingRequest = new UpdateRebalancingRequest()
    .withClusterArn(arn:aws-eusc:kafka:eusc-de-east-1:123456789012:cluster/myCluster/abcd1234-5678-90ef-ghij-klmnopqrstuv-1)
    .withCurrentVersion(ABCDEF1GHIJK0L)
    .withRebalancing(new Rebalancing().withStatus("PAUSED"));