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Low disk space



My PRTG server is running out of disk space. I understand if I decrease the global setting for 'Historic Sensor Data' from 365 days, then my disk usage will go down.

However, I still want to keep 365 days for most of my devices. But I have a bunch of devices that I do not need to keep long-term.

I would like to know if there is any danger in me manually purging some of the deviceXXXX.prd files from the \Monitoring Database\yyymmdd\ folders? Will I cause corruption if I purge some of those files?

disk historic-data prd

Created on Jan 26, 2021 8:46:37 PM

1 Reply



Hello Reynold,

Thank you very much for your question.

A significant growth in data size, depending on the number of sensors, purging period is expected. For instance, we estimate a required disk space of 750GB for up to 2,500 sensors.
Please see our System Requirementsfor further details.

I specifically have to say that I would not recommend manually deleting .prd files. From user perspective deleting those fles will simply free disk space and break graphs that rely on historic data but there are many internal dependencies. There is a certain risk here and Paessler Tech Support will not be able to troubleshoot any caused data loss in those cases.


Created on Jan 28, 2021 9:42:42 AM by  Sebastian Kniege [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.