Logging of log line attempted (10kB) over max size (10kB)

[Andrew Watson]

After updating a Mongo replica set to 3.6.11, I see these warnings in the log:

2019-03-19T15:18:26.158-0400 I REPL     [repl writer worker 4] warning: log line attempted (10kB) over max size (10kB), printing beginning and end ... applied op: CRUD 

They are coded as REPL events, and are therefore triggering alerts based on REPL events. I don't believe this is indicating a real issue in my case, but I'd like to be able to disable these alerts, or change the code so I don't need to modify the alert. (Other REPL events are worth alerting, on - I don't think this one is).

Thanks for any insight.

Andrew

[Wan Bachtiar]

They are coded as REPL events, and are therefore triggering alerts based on REPL event

Hi Andrew,

What kind of alerts are you referring to ? i.e. custom alerts or MongoDB Atlas alerts.
If this is a custom alerts based on log entries, are you able to configure the alerts to ignore these log entries ?

I don’t believe this is indicating a real issue in my case

To clarify, this is the logger truncating log messages that are larger than 10kB size (default).

Regards,
Wan.

​

[Andrew Watson]

They are custom alerts, these logs go into Splunk, and Splunk alerts based on patterns found in the logs. 

I guess the question is why these messages, indicating a normal truncation of a log event, seem to now contain the REPL message code. I guess I can modify the Splunk alert to ignore THIS kind of REPL message, but alert on other kinds, but it seems like a clumsy workaround.

[Andrew Watson]

Just to close the loop on this in case anyone else runs into it - we believe the logging behavior change was related to:

https://jira.mongodb.org/browse/SERVER-32146