Why the consumer can not consume the message about a cluster with two broker

[kengan]

I have setup a rocketmq cluster with 2 master and 1 namesrv.
I make 2 consumer program with rocketmq-spring-boot-starter 2.2.0 and Spring boot 2.3.8. The main program abouot consumer is as following:

package com.cesc.iot.handle.handler;

import org.apache.rocketmq.spring.annotation.RocketMQMessageListener;
import org.apache.rocketmq.spring.core.RocketMQReplyListener;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.stereotype.Service;

@service
@RocketMQMessageListener(topic = "${iot.rocketmq.topic}", consumerGroup = "iot_message_consumer")
public class IotMessageHandler implements RocketMQReplyListener<String,String> {
private static final Logger logger = LoggerFactory.getLogger("BackgroundLogger");
@OverRide
public String onMessage(String message) {
logger.info("recevice message from mq:"+message);
return "ok";

}

}

But I found that 2 consumer only consume the message in a broker.
When stop one broker every thing is OK, but when I open two broker, some message in other broker can not be consume. Please see the following image about rocketmq-console

Can you tell me why？ Thank you

[kengan]

[maixiaohai]

We met the same problem when start consumer using docker container.
The root cause is two consumers have same instance name.

[maixiaohai]

@kengan I submit a pr to fix this problem, you can have a test on it.

[kengan]

@maixiaohai I can confirm that this problem happen when start consumer using docker container. The root cause is two consumers have same instance clientId

[kengan]

@maixiaohai how to test your fix?

[maixiaohai]

@maixiaohai how to test your fix?

git fetch apache pull/342/head:pr342

[RongtongJin]

clientid设置为ip@client本质上是为了让多个consumer或producer复用同一个网络模块，在容器中启动确实存在这样的问题，可以暂时通过在prepareStart方法（wiki第8条）中setInstanceName设置不同的instanceName来解决。