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Commit data to database before a reboot



We just encountered an issue where our monitoring graphs encountered an 4hr loss of data following a reboot for monthly security patching. Prior to the reboot the data was displaying just fine.

Is there a temporary sensor data cache that we can manually trigger to commit to the database before we reboot? One of 10GigE Bandwidth Sensors had graph data displaying just fine until we rebooted. Post reboot the last 4 hours were missing.

bandwidth monitoring-database prtg8

Created on Aug 15, 2011 4:34:09 PM

1 Reply




this might be just a caching issue, PRTG does save historic much more often (about every 5-15 minutes). Please try 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 -> PRTG Status-> 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

It is very important, that the PRTG Core Service has enough time to properly shut down, and finish writing it's Graph Cache File. So it might be better in some cases to shut down the PRTG Services 10-15 minutes before actually rebooting the host server. A few users do this with a batch-script and the net stop and shutdown /r-commands.

best regards

Created on Aug 15, 2011 5:43:23 PM 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.