Controller 1005 epoch 84 received response {error_code=0}

[#1]

Hello, I am regularly seeing this error in the state-change.log on my production cluster and was wondering if this is something to worry about.

prod.cmla.metrics-15 in response to UpdateMetadata request sent by controller 1005 epoch 84 with correlation id 1083 (state.change.logger)
[2019-08-21 04:18:18,862] TRACE Controller 1005 epoch 84 received response {error_code=0} for a request sent to broker  (id: 1005 rack: null) (state.change.logger)
[2019-08-21 04:18:18,863] TRACE Controller 1005 epoch 84 received response {error_code=0} for a request sent to broker  (id: 1002 rack: null) (state.change.logger)

[#2 · Accepted solution]

@paleerbccm 

Briefly looking at the message, I would assume 'error_code=0' actually means that no errors occurred. It  would need quite a bit of digging in the code to understand, but generally speaking, I wouldn't worry too much about TRACE level logs. 

Ideally, and especially that this is a production environment, you would normally set logging level to INFO and that's about all you would need. Unless you have an intimate knowledge of the code and you're chasing after a specific issue, it's rare that you would ever need TRACE level logs.