Data plane FAQ

• Where are the MSHA-agent logs?
• Why does the log entry brokerName=msha_mock_queueBrokerName appear in the ons.log file of RocketMQ Enterprise Edition after traffic to an active zone-redundancy cell is cut off?
• For active geo-redundancy, how to check if the MSHA-agent has fetched the routing tag from HTTP traffic?

Where are the MSHA-agent logs?

The MSHA-agent log directory is ~/logs/msha/agent.$processId.$localIdentity/. Each process has its own log directory.

The following figure shows the MSHA-agent log directory:

The main log files to check are:

• agent.log: Startup log.
• agent_plugin.log: Contains logs for the agent plugin's Aspect-Oriented Programming (AOP) aspect.
• agent_error.log: Error log for the agent.

Why does the log entry brokerName=msha_mock_queueBrokerName appear in the ons.log file of RocketMQ Enterprise Edition after traffic to an active zone-redundancy cell is cut off?

The log entry is as follows:

2021-03-31 23:59:34,034 INFO RocketmqClient  
- topicRouteTable.put.Topic = MQ_INST_1815555058395900_BbCHFzvM%xiniao_pra_callback, 
TopicRouteData
[TopicRouteData
 [orderTopicConf=null, queueDatas=
  [QueueData
    [brokerName=msha_mock_queueBrokerName, readQueueNums=8, writeQueueNums=8, perm=6, topicSynFlag=0]
  ], 
brokerDatas=
 [BrokerData
   [brokerName=msha_mock_brokerName, brokerAddrs={0=1.2.3.4:80}]
 ], 
filterServerTable={}
 ]
]

This log entry indicates that RocketMQ is updating the IPAM pool information (topicRouteTable.put). The brokerName=msha_mock_brokerName is a virtual broker name that the MSHA-agent adds after filtering the IPAM pool. This entry confirms that the traffic cut-off is in effect and the machine will no longer consume messages.

For active geo-redundancy, how do I check if MSHA-agent has fetched the routing tag from HTTP traffic?

You can check the agent_plugin.log file. This file contains two log entries, `before` and `after`, for the servlet aspect. In the following example, routeId:JoeHeader indicates that the fetched routing tag is JoeHeader.

2021-05-13 15:12:39,750 INFO http-nio-7004-exec-1 
com.alibaba.msha.agent.plugin.servlet.trace.ServletEnhancerHandler 
- beforeAdvice invoked, url:http://localhost:7004/echo/xx, httpRouteIdConfigs:{5bec72a6-8e0c-4ad1-9846-87e2442bd034=HttpRouteIdConfig{routeType='default', routeIdSources=[arg, header, cookie], routeIdKey='key123yyybbbb'}}, httpHeader:{host=localhost:7004, user-agent=curl/7.54.0, accept=*/*, key123yyybbbb=JoeHeader}, httpCookie:{} 
2021-05-13 15:12:39,751 INFO http-nio-7004-exec-1 
com.alibaba.msha.agent.plugin.servlet.trace.ServletEnhancerHandler 
- routeId found in HTTP flow, routeId:JoeHeader, routeIdSource:header, routeIdKey:key123yyybbbb