Changing Kafka Partition Quantity

Changing the Number of Topic Partitions (Console)

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

   Select the region where your Kafka instance is located.

3. Click Service List and choose Application > Distributed Message Service. The Kafka instance list is displayed.
4. Click the desired Kafka instance to view the instance details.
5. In the navigation pane, choose 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 and click OK.
   

   • The number of partitions can only be increased.
   • To ensure performance, the Kafka console allows a maximum of 200 partitions for each topic.
   • The total partitions of all topics cannot exceed the maximum partitions of an instance. The maximum partitions of an instance varies by instance specifications. For details, see Specifications.

Changing the Number of Topic Partitions (Client)

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

For an instance with ciphertext access enabled, if allow.everyone.if.no.acl.found is set to false, topic partition quantity cannot be modified through the client.

• 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}

  Parameter description:

  • connection-address: can be obtained from the Connection area on the Basic Information page on the Kafka console.
  • topic-name: topic name.
  • number-of-partitions: number of partitions in a 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) Modify the client configuration file.
     View Security Protocol in the Connection area on the Basic Information page on the Kafka console. The configuration settings vary depending on the protocol.

     • SASL_PLAINTEXT: Skip this step if the username and password are already set. Otherwise, create the ssl-user-config.properties file in the /config directory on the Kafka client and add the following content to the file:

       security.protocol=SASL_PLAINTEXT
       # If the SASL mechanism is SCRAM-SHA-512, configure as follows:
       sasl.jaas.config=org.apache.kafka.common.security.scram.ScramLoginModule required \
       username="**********" \
       password="**********";        
       sasl.mechanism=SCRAM-SHA-512
       # If the SASL mechanism is PLAIN, configure as follows:
       sasl.jaas.config=org.apache.kafka.common.security.plain.PlainLoginModule required \
       username="**********" \
       password="**********";        
       sasl.mechanism=PLAIN

       Parameter description: username and password are the ones you set when enabling ciphertext access for the first time or when creating a user.

     • SASL_SSL: Skip this step if the username, password, and SSL certificate are already set. Otherwise, create the ssl-user-config.properties file in the /config directory on the Kafka client and add the following content to the file:

       security.protocol=SASL_SSL
       ssl.truststore.location={ssl_truststore_path}
       ssl.truststore.password=dms@kafka
       ssl.endpoint.identification.algorithm=
       # If the SASL mechanism is SCRAM-SHA-512, configure as follows:
       sasl.jaas.config=org.apache.kafka.common.security.scram.ScramLoginModule required \
       username="**********" \
       password="**********";        
       sasl.mechanism=SCRAM-SHA-512
       # If the SASL mechanism is PLAIN, configure as follows:
       sasl.jaas.config=org.apache.kafka.common.security.plain.PlainLoginModule required \
       username="**********" \
       password="**********";        
       sasl.mechanism=PLAIN

       Parameter description:

       • ssl.truststore.location: path for storing the client.jks certificate. Even in Windows, you need to use slashes (/) for the certificate path. Do not use backslashes (\), which are used by default for paths in Windows. Otherwise, the client will fail to obtain the certificate.
       • ssl.truststore.password: server certificate password, which must be set to dms@kafka and cannot be changed.
       • ssl.endpoint.identification.algorithm: whether to verify the certificate domain name. This parameter must be left blank, which indicates disabling domain name verification.
       • username and password: username and password you set when enabling ciphertext access for the first time or when creating a user.
  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 

     Parameter description:

     • connection-address: can be obtained from the Connection area on the Basic Information page on the Kafka console.
     • topic-name: topic name.
     • number-of-partitions: number of partitions in a topic.

     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]#