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How do I make PRTG write monitoring data to the disk more frequently?



I have a system runs PRTG Network Monitor and it tends to crash (not related to PRTG mind you).

The problem is when it crashes it seems to loose huge chunks of data from being saved due to the write interval of the saved data (my graphs show large gaps).

Is there a way to get PRTG Network Monitor to save these stats to disk sooner? Say, once every hour? Once every 30 minutes? 10 minutes? 1 minute?

Granted 1 minute is excessive but being able to change that would help salvage its crash and dumping 4-5 hours of collected data all because it simply wasn't written yet.

If someone could either implement that (or simply tell me where I overlooked it) I would be very grateful.


cache data history prtg recalc recovery save-data write-interval

Created on Mar 4, 2010 12:27:26 AM

Last change on Mar 5, 2010 1:17:41 PM by  Daniel Zobel [Product Manager]

1 Reply

Accepted Answer



PRTG writes to the disk constantly.

What you are experiencing is that when your PC does crash that the PRTG cache can not be written to the disk and then PRTG uses the existing cache at the next startup.

The cache is used to enable a faster start of the software.

You can recalculate your data by doing the following

  • Stop both PRTG services (core and probe).
  • Head to your data folder (can be discerned from the Server Administrator tool, under the "Core Server" tab)
  • Delete the "PRTG Graph Data Cache.dat" file
  • Restart the PRTG services
  • Log in to the Web GUI
  • Go to "Setup -> System Status" and check the background tasks. It should state that it is calculating historic data


  • Refresh the page from time to time (is the number being reduced?)
  • Let it run until it is done and then take a look at the historic data of your sensors - it should now be available

Created on Mar 4, 2010 6:09:51 AM by  Aurelio Lombardi [Paessler Support]

Last change on Mar 4, 2010 10:38:54 AM by  Torsten Lindner [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.