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If a log file is rotated then its name is appended the current date and a running number, in addition the log file is compressed, e.g. a log file controller.log becomes controller-2021-01-31-1.log.gz. The running number 1 indicates the first log file of the day being rotated.

Users are free to modify the Log4j2 configuration to apply their individual log rotation strategy, see below examples explained.

As an exception to this rule the watchdog log files for Controller and Agent are not subject to log rotation. The watchdog log file captures any output before the respective application is started, e.g. output of the Controller Windows Service, and therefore does not make use of Log4j2 for logging. The watchdog log files therefore should not grow but should report a few lines only in situations when a Controller or Agent could not be started.

Log Retention

By default the log retention period for any log files is 30 days, i.e. log files older than this will be removed..

Users are free to modify the Log4j2 configuration to apply their individual log retention period, see below examples explained.

Log retention This does not apply to

• the audit.log log file that is rotated but is not subject to log retention and therefore is not removed

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• or truncated. For compliance reasons the audit.log remains in place for an arbitrary duration. It's the user's responsibility to purge the audit.log to their requirements.
• the watchdog.log files of Controller and Agent that hold any output created before starting the respective application. 

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Configuration Files explained

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