Creating a RocketMQ Consumer Group

Prerequisites

A RocketMQ instance has been purchased.

Creating a RocketMQ Consumer Group

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

   Select the region where your RocketMQ instance is located.

3. Click and choose Application > Distributed Message Service for RocketMQ to open the console of DMS for RocketMQ.
4. Click a RocketMQ instance to go to the instance details page.
5. In the navigation pane, choose Consumer Groups.
6. Click Create Consumer Group.
7. Configure the consumer group name and other parameters by referring to Table 1.

   Table 1 Consumer group parameters

   Parameter	Description
   Consumer Group Name	Name of the consumer group. A consumer group must meet the following requirements: Contains 3 to 64 characters. Contains only letters, digits, percent signs (%), vertical bars (|), hyphens (-), and underscores (_). Once the consumer group is created, you cannot modify its name.
   Brokers	This parameter is mandatory when the RocketMQ instance version is 4.8.0. Select one or multiple brokers to create consumer groups as required. The consumer groups are automatically created. Once the consumer group is created, you cannot modify its brokers.
   Maximum Retries	Maximum number of retry attempts allowed for normal messages. Value range: 1–16 For ordered retrievals, this limit can be configured by using the setMaxReconsumeTimes method.
   Broadcast	Indicates whether messages are broadcast. If this option is enabled, each message is retrieved by all consumers in the consumer group. If this option is disabled, each message is retrieved by only one consumer in the consumer group.
   Orderly	This parameter is mandatory when the RocketMQ instance version is 5.x. If this option is enabled, consumers consume messages in sequence. Orderly consumption ensures sequential consumption by message sending. In this case, earlier messages are consumed before later messages
   Description	Description of the consumer group. 0–200 characters

8. Click OK.

   View Consumption Model on the consumer group list page once a consumer group is created.

   • CLUSTERING: cluster consumption mode. RocketMQ consumes any message by any consumer in the consumer group.
   • BROADCASTING: broadcast consumption mode. RocketMQ pushes each message to all consumers in the consumer group to ensure that the message is consumed by each consumer.

   Consumption Model is -- when the consumer group is offline.