Changing Kafka Partition Quantity

Notes and Constraints

• The number of partitions can only be increased.
• The total number of partitions in topics is limited. When the partition quantity limit is reached, you can no longer create topics. The total number of partitions varies with instance specifications. For details, see Specifications.
• For an instance with ciphertext access enabled, if allow.everyone.if.no.acl.found is set to false, the topic partition quantity can be modified on the client only by the initial user (set in instance creation).
• A maximum of 50 partitions can be modified in a batch at a time.

Repartitioning a Topic on the Console

1. Log in to the console.
2. Click in the upper left corner to select the region where your instance is located.
3. Click in the upper left corner and choose Application > Distributed Message Service for Kafka to open the Kafka instance list.
4. Click the desired instance to go to the instance details page.
5. In the navigation pane, choose Instance > Topics.
6. Modify the number of partitions using either of the following methods:
   • Select one or more topics and click Edit Topic in the upper left corner.
   • In the row containing the desired topic, click Edit.

7. In the Edit Topic dialog box, enter the number of partitions by referring to Table 1, and click OK.

   Table 1 Partitions parameters

   Parameter	Description
   Partitions	Enter the number of partitions. The number of partitions can only be increased. To ensure performance, a maximum of 200 partitions is allowed for each topic on the Kafka console.
   Broker	Set the broker where the new partition is located. Auto: The Kafka service automatically allocates brokers to the new partition. Specified: Select brokers from the drop-down list box. The number of brokers cannot be less than the number of topic replicas.

   View the partition quantity on the Topics page.

Modifying the Number of Partitions in Batches

1. Log in to the console.
2. Click in the upper left corner to select the region where your instance is located.
3. Click in the upper left corner and choose Application > Distributed Message Service for Kafka to open the Kafka instance list.
4. Click the desired instance to go to the instance details page.
5. In the navigation pane, choose Instance > Topics.
6. Select the desired topics and click Batch Edit Topic on the upper left.
7. In the Batch Operations area, select Partitions and enter a value. In the Preview Change area, view the unchanged and changed item. Click OK.

   The number of partitions is subject to the following constraints:

   • To ensure performance, a maximum of 200 partitions is allowed for each topic on the Kafka console.
   • This value must be set to a value greater than or equal to the maximum number of partitions among the topics. For example, when topic Topic01 has three partitions and topic Topic02 has six partitions, the value must be greater than or equal to 6.
   Figure 1 Batch modifying the number of partitions
   

   View the partition quantity on the Topics page.

Modifying Topic Partitions on Kafka Manager

1. Log in to Kafka Manager.
2. Choose Topic > List to view the list of topics.
3. Click a topic to view its details.
4. Click Add Partitions.
   Figure 2 Topic details page
   

5. Enter the number of partitions and click Add Partitions.
   To ensure performance, 200 or less partitions are recommended for each topic.

   Figure 3 Adding partitions
   

   If "Done" is displayed, the partitions are added successfully.

   Figure 4 Partitions added
   

Modifying Topic Partitions on the Client

If your Kafka client version is later than 2.2, you can use kafka-topics.sh to change the partition quantity.

• For a Kafka instance with ciphertext access disabled, run the following command in the /bin directory of the Kafka client:

  ./kafka-topics.sh --bootstrap-server {connection-address} --topic {topic-name} --alter --partitions {number-of-partitions}

  Table 2 Topic partition quantity parameters

  Parameter	Description
  connection-address	Connection address of a Kafka instance. To obtain the address, choose Overview > Connection.
  topic-name	Topic name.
  number-of-partitions	Number of partitions in the topic. To ensure performance, 200 or fewer partitions are recommended for each topic.

  Example:

  [root@ecs-kafka bin]# ./kafka-topics.sh --bootstrap-server 192.168.xx.xx:9092,192.168.xx.xx:9092,192.168.xx.xx:9092 --topic topic-01 --alter --partitions 6
  [root@ecs-kafka bin]#

• For a Kafka instance with ciphertext access enabled, do as follows:
  1. (Optional) If the username and password, and the SSL certificate has been configured, skip this step and go to 2. Otherwise, do as follows:

     Create the ssl-user-config.properties file in the /config directory of the Kafka client. Add the username and password, and the SSL certificate configuration by referring to 3.

  2. Run the following command in the /bin directory of the Kafka client:

     ./kafka-topics.sh --bootstrap-server {connection-address} --topic {topic-name} --alter --partitions {number-of-partitions} --command-config ../config/{ssl-user-config.properties} 

     Table 3 Topic partition quantity parameters

     Parameter	Description
     connection-address	Connection address of a Kafka instance. To obtain the address, choose Overview > Connection.
     topic-name	Topic name.
     number-of-partitions	Number of partitions in the topic. To ensure performance, 200 or fewer partitions are recommended for each topic.
     ssl-user-config.properties	Configuration file name. This file contains username, password, and SSL certificate information.

     Example:

     [root@ecs-kafka bin]# ./kafka-topics.sh --bootstrap-server 192.168.xx.xx:9093,192.168.xx.xx:9093,192.168.xx.xx:9093 --topic topic-01 --alter --partitions 6 --command-config ../config/ssl-user-config.properties
     [root@ecs-kafka bin]#