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Erroneous Disk Free notifications




My probe device is continuously flicking between Disk Free 0% and 52%. I am on the latest unstable build - so should I be submitting faults somewhere rather than asking here?



Cheers James

prtg12beta server-2008-r2-wmi wmi-free-disk-sensor

Created on Dec 3, 2012 12:37:17 AM

1 Reply




unfortunately, we don't have a solution for the problem when WMI Free Disk Space Sensors (Multi Drive) report 0 free space for a short period. We have seen it from a few other customers as well, and once in our lab. In those incidents the WMI Responses are really '0'-values directly from the monitored host (so the WMI Counter on the host reports a wrong value for a short time). We do not know why this happens, I'm afraid. Please try using the "WMI Volume"- Sensor ("WMI Free Disk Space (Single Drive)" in PRTG 8), for some users this sensor did not show this problem.

Unfortunately WMI is not the most stable and reliable platform for monitoring, so it seems, please also see the following WMI-Troubleshooting articles:



Created on Dec 3, 2012 3:58:01 PM by  Torsten Lindner [Paessler Support]

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