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My PRTG has stopped graphing

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After an unexpected power cycle, prtg has stopped graphing. the tables are updating but not the graphs. How do I repair this. How to do a cache recalculation?

cache fail graph graphs prtg

Created on Mar 23, 2010 7:53:29 AM

Last change on May 28, 2013 1:43:12 PM by  Daniel Zobel [Product Manager]



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Accepted Answer

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This article applies to PRTG Network Monitor 14 or later

No Data Displayed in PRTG Live Graph

Please reset (delete) the graph cache so PRTG can rebuild it.

Option 1: Automatically

In current PRTG versions, you can recalculate the graph cache directly from the PRTG web interface. In previous version, use one of the other options.

  • Open the PRTG web interface.
  • Select Setup | System Administration | Administrative Tools from the main menu bar.
  • Navigate to section Recalculate PRTG Graph Data Cache.
  • Click on the Go! button to start the recalculation.

Note: This will trigger a restart of your PRTG core server.


In previous PRTG versions as of PRTG 12, you find the graph recalculation option in the PRTG Server Administrator tool.


Option 2: Manually

  • Stop both PRTG services (core and probe).
  • Navigate to your data folder (You can look it up in the PRTG Administration Tool on the Core Server tab. See this article for detailed information.)
  • Delete the PRTG Graph Data Cache.dat file
  • Restart the PRTG services

After Cache Reset

  • Log in to the PRTG web interface
  • Go to Setup | PRTG Status | System Status and check the background tasks. It should state that it is calculating historic data.

Then,

  • Refresh the page from time to time (is the number being reduced?)
  • Let it run until it is done and then check if your graph is available.
  • Note: System performance may be a affected while recalculation is running

Created on Mar 23, 2010 3:59:08 PM by  Daniel Zobel [Product Manager]

Last change on Feb 18, 2015 4:23:46 PM by  Gerald Schoch [Paessler Support]



6 Replies

Votes:

0

did you already try to restart the server?

Created on Mar 23, 2010 8:09:35 AM by  Aurelio Lombardi [Paessler Support]



Accepted Answer

Votes:

0

This article applies to PRTG Network Monitor 14 or later

No Data Displayed in PRTG Live Graph

Please reset (delete) the graph cache so PRTG can rebuild it.

Option 1: Automatically

In current PRTG versions, you can recalculate the graph cache directly from the PRTG web interface. In previous version, use one of the other options.

  • Open the PRTG web interface.
  • Select Setup | System Administration | Administrative Tools from the main menu bar.
  • Navigate to section Recalculate PRTG Graph Data Cache.
  • Click on the Go! button to start the recalculation.

Note: This will trigger a restart of your PRTG core server.


In previous PRTG versions as of PRTG 12, you find the graph recalculation option in the PRTG Server Administrator tool.


Option 2: Manually

  • Stop both PRTG services (core and probe).
  • Navigate to your data folder (You can look it up in the PRTG Administration Tool on the Core Server tab. See this article for detailed information.)
  • Delete the PRTG Graph Data Cache.dat file
  • Restart the PRTG services

After Cache Reset

  • Log in to the PRTG web interface
  • Go to Setup | PRTG Status | System Status and check the background tasks. It should state that it is calculating historic data.

Then,

  • Refresh the page from time to time (is the number being reduced?)
  • Let it run until it is done and then check if your graph is available.
  • Note: System performance may be a affected while recalculation is running

Created on Mar 23, 2010 3:59:08 PM by  Daniel Zobel [Product Manager]

Last change on Feb 18, 2015 4:23:46 PM by  Gerald Schoch [Paessler Support]



Votes:

0

now my sensors are showing up as ? and still no data

Created on Dec 15, 2010 11:43:16 PM



Votes:

0

hallo,

please open a support ticket by sending a mail to [email protected]

and please forward us your system log files for analysis? You can find the same under

XP/2003: C:\Documents and Settings\All Users\Application Data\Paessler\PRTG Network Monitor\V7\Logs (System) Vista/2008: C:\ProgramData\Paessler\PRTG Network Monitor\V7\Logs (System)

Created on Dec 25, 2010 4:15:17 PM by  Aurelio Lombardi [Paessler Support]



Votes:

0

dear paessler,

I am also facing the same issue.

My live graph is not rendering and some of the sensors are not working.

please help

Created on Dec 24, 2015 3:42:06 PM



Votes:

0

Dear Brun

Did you already try to delete the Graph Data cache? "Option 2: Manually" is the best way to enforce a Graph Data cache recalculation. Once the previous cache has been deleted, it can take some hours to rebuild a new cache.

Created on Dec 25, 2015 1:15:31 PM by  Arne Seifert [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.