Updated on 2023-08-18 GMT+08:00

Modifying Instance Specifications


After creating a Kafka instance, you can expand its storage space and increase the number of brokers.

Notes and Constraints

  • You can expand the storage space 20 times.
  • If you increase the number of brokers, the maximum number of partitions will also be increased. When brokers are added, the storage space is proportionally expanded based on the current disk space. For example, assume that the original number of brokers of an instance is 3 and the disk size of each broker is 200 GB. If the broker quantity changes to 10 and the disk size of each broker is still 200 GB, the total disk size becomes 2000 GB.


  1. Log in to the management console.
  2. Click in the upper left corner to select a region.

    Select the region where your Kafka instance is located.

  3. Click and choose Application > Distributed Message Service (for Kafka) to open the console of DMS for Kafka.
  4. In the row containing the instance for which you want to modify the specifications, choose More > Modify Specifications in the Operation column.
  5. Specify the required storage space or the number of brokers.

    The storage space and the number of brokers can only be changed separately.

    • Expand the storage space.

      For Modify By, select Storage. For Storage Space per Broker, specify a new storage space, and click Next. Confirm the configurations and click Submit.

      View the new storage space (Storage space per broker x Number of brokers) in the Used/Available Storage Space (GB) column in the instance list.

      • Storage space expansion does not affect services.
      • Available storage space = Actual storage space – Storage space for storing logs and ZooKeeper data – Disk formatting loss

        For example, if the storage space is expanded to 700 GB, the storage space for storing logs and ZooKeeper data is 100 GB, and the disk formatting loss is 7 GB, then the available storage space after capacity expansion will be 593 GB.

    • Add brokers.

      For Modify By, select Brokers. Then, enter the number of brokers and click Next. Confirm the configurations and click Submit.

      View the number of brokers in the Specifications column in the instance list.

      • Adding brokers does not affect the original brokers or services.
      • New topics are created on new brokers, and the original topics are still on the original brokers, resulting in unbalanced partitions. You can reassign partitions to migrate the replicas of the original topic partitions to the new brokers.
      • After adding brokers, add the IP addresses of the new brokers to the client connection configuration to improve reliability.