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Mark a file sensor as DOWN when file size beyond a threshold




I'm using the File sensor in PRTG to monitor SQL Server log files, Specifically, I have thresholds set up to alert me if a log file grows beyod 4GB as that indicates a problem with our SQL scripts. However I seem only able to get ticket/alert notification, I can't seem to mark the sensor as DOWN when the 4GB size is reached. The only option for DOWN seems to be dependent on a file existing or not existing.

Can anyone suggest how I may achieve this please? Mark a file sensor as DOWN if the file size is beyond a certain size.

Many thanks


file prtg sensor size

Created on Jul 1, 2015 8:43:12 PM

2 Replies



Simply click the small gear within the channel panel that monitors the log file size and enable the limits at the very bottom. Then you can fire notifications when a certain channel reaches the defined thresholds.

See also the Paessler website: How to set up notifications via the PRTG web interface.

Created on Jul 2, 2015 9:00:39 AM by  Stephan Linke [Paessler Support]

Last change on Jul 26, 2021 11:32:47 AM by  Maike Guba [Paessler Support] (2,404) 2 1



Perfect!!!!! Thank you! Those settings are well hidden.....

Created on Jul 4, 2015 6:30:26 PM

Disclaimer: The information in the Paessler Knowledge Base comes without warranty of any kind. Use at your own risk. Before applying any instructions please exercise proper system administrator housekeeping. You must make sure that a proper backup of all your data is available.