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  1. Percona Monitoring and Management
  2. PMM-4806

Using -collect.collection against mongos nodes causes log bloat in mongos log

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      There is a logging bug affecting mongos nodes in v3.6+: https://jira.mongodb.org/browse/SERVER-36801

      In short when the -collect.collection option is used every call to collStats (or aggregation $collStats) prints 5 or so lines with an warning message "mongos collstats doesn't know about: xxxx". If you have say 100 collections then that's 500 log lines being added everytime the mongodb_exporter is run against the mongos node. This can lead to a disk-full incident soon enough.

      I don't think we should run -collect.collection on a mongos node. The option used against the mongod nodes adds up to the same stats. So I think its fine to stop -collect.collection on mongos nodes in PMM. I suggest that as a fix to this issue.

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              • Assignee:
                Unassigned
                Reporter:
                akira.kurogane Akira Kurogane
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                • Created:
                  Updated: