Modifying Cluster Kafka Instance Specifications
After creating a Kafka instance, you can increase or decrease its specifications. Table 1 lists available modification options. Only one object can be modified per operation: broker quantity, storage space, or broker flavor.
Modified Object |
Increase |
Decrease |
---|---|---|
Broker quantity |
√ |
× |
Storage space |
√ |
× |
Broker flavor |
√ |
√ |
Notes and Constraints
Unavailable for single-node instances.
Impact of Specification Modification
Modified Object |
Impact |
---|---|
Broker quantity |
|
Storage space |
|
Broker flavor |
|
Process of Increasing or Decreasing Broker Flavors
When you scale up or down the broker flavor, a rolling restart is performed on brokers. The following process takes three brokers as an example:
- Stop the Kafka process on Broker 0.
- Scale up or down the flavor of Broker 0.
- Restart the Kafka process on Broker 0.
- Repeat 1 to 3 to scale up or down the flavor of Broker 1.
- Repeat 1 to 3 to scale up or down the flavor of Broker 2.

Procedure
- Log in to the console.
- Click
in the upper left corner to select the region where your instance is located.
- Click
and choose Application > Distributed Message Service (for Kafka) to open the console of DMS for Kafka.
- In the row containing the desired instance, choose More > Modify Specifications in the Operation column.
- Specify the storage space, number of brokers, or broker flavor as required.
- Expand the storage space.
- For Change By, select Storage. For Storage space per broker, specify a new storage space, and click Next. The storage space range varies by instance specifications. For details, see Specifications.
- Confirm the configurations and click Submit.
- Check the modification progress and estimated remaining time.
- In the instance list, click the instance to go to the instance details page.
- In the navigation pane, choose Background Tasks.
- Click the task whose name is Modify Specifications. The Specification Modification Task Details dialog box is displayed.
- Check the progress and estimated remaining time. In Steps, check the steps, start time, and end time.
- Check whether the modification is successful.
- If the task is in the Successful state, the modification is successful. View the new storage space (Storage space per broker × Number of brokers) in the Used/Available Storage Space (GB) column in the instance list.
- If the task is in the Failed state, the modification is not successful. Move the cursor over Failed or check the cause in Steps.
After the modification fails, the instance is in the Change failed state, and cannot be restarted, modified, or deleted. After the instance status automatically changes from Change failed to Running, you can continue to perform operations. If the status does not change to Running, contact customer service.
- Add brokers.
- For Change By, select Brokers.
- For Brokers, specify the broker quantity. The broker quantity varies by instance flavor. For details, see Cluster Kafka Instances.
- If public access has been enabled, configure EIPs for the new brokers.
- For Subnet, retain the default settings.
- For Private IP Addresses, select Auto or Manual.
- Auto: The system assigns an IP address from the subnet automatically.
- Manual: Select the IP addresses for the new brokers from the drop-down list. If the number of selected IP addresses is less than the number of brokers, the remaining IP addresses will be automatically assigned.
- Click Next.
- Confirm the configurations and click Submit.
- Check the modification progress and estimated remaining time.
- In the instance list, click the instance to go to the instance details page.
- In the navigation pane, choose Background Tasks.
- Click the task whose name is Modify Specifications. The Specification Modification Task Details dialog box is displayed.
- Check the progress and estimated remaining time. In Steps, check the steps, start time, and end time.
- Check whether the modification is successful.
- If the task is in the Successful state, the modification is successful. View the number of brokers in the Flavor column in the instance list.
- If the task is in the Failed state, the modification is not successful. Move the cursor over Failed or check the cause in Steps.
After the modification fails, the instance is in the Change failed state, and cannot be restarted, modified, or deleted. After the instance status automatically changes from Change failed to Running, you can continue to perform operations. If the status does not change to Running, contact customer service.
- After adding brokers, add the IP addresses of the new brokers to the client connection configuration to improve reliability.
- Increase or decrease the broker flavor.
- For Change By, select Broker Flavor.
- Specify a new broker flavor.
- In the Risk Check area, check for risks.
If any risk is found, handle it as prompted and click Recheck. If the risks do not need to be handled, select I understand the risks.
- Click Next, confirm the information, and click Submit.
- Check the scaling progress and estimated remaining time.
- In the instance list, click the instance to go to the instance details page.
- In the navigation pane, choose Background Tasks.
- Click the task whose name is Modify Specifications. The Specification Modification Task Details dialog box is displayed.
- Check the progress and estimated remaining time. In Steps, check the steps, start time, and end time.
- Check whether the modification is successful.
- If the task is in the Successful state, the modification is successful. View the broker flavor in the Flavor column in the instance list.
- If the task is in the Failed state, the modification is not successful. Move the cursor over Failed or check the cause in Steps.
After the modification fails, the instance is in the Change failed state, and cannot be restarted, modified, or deleted. After the instance status automatically changes from Change failed to Running, you can continue to perform operations. If the status does not change to Running, contact customer service.
- Expand the storage space.
Feedback
Was this page helpful?
Provide feedbackThank you very much for your feedback. We will continue working to improve the documentation.