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Monitor unusual disk growth




We have several MS SQL DB servers.

Sometimes we have problem with database files growth and we know about only when Warning or Error tell us.

For example, disk free space is 100Gb, warning limit is set to 50Gb, Error limit to 20Gb.

We had situation with db error and SQL server created every 5 minutes one file 2Mb size. After half a day we noticed problem when we were running out of free disk space.

Is there any option to predict such situation and set PRTG to send notifications when it notice such abnormal disk behavior ?

disk disk-free prtg unusual

Created on Jun 20, 2018 11:45:38 AM

1 Reply



Hi Greg,

Please navigate to "Setup | System Administration | Monitoring", to find the setting "Unusual Detection".

To detect unusual behavior PRTG checks the latest measurements against previously measured values. Unusual detection works with two methods:

  • Daily (24h): The average of the day before is compared to previous daily averages of the same weekday
  • Hourly: The average of the previous hour is compared to previous hourly averages of the same weekday and the same hour-of-day

Please also find additional information here (please search for "unusual"): https://www.paessler.com/manuals/prtg/monitoring_settings

Kind regards
Andreas Günther, Technical Support

Created on Jun 21, 2018 10:45:35 AM by  Andreas Günther [Paessler Support]

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.