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I have installed PRTG on a system with a 10+ TB volume; WMI Disk Free sensor



The "WMI Disk Free" sensor is setup by default on the probe device, but shows 0% free. I also manually added the WMI Volume sensor and it shows the same 0% status. How can I get an accurate report on this?

disk-free gpt prtg wmi

Created on Jun 23, 2010 7:08:18 PM

Last change on Jun 25, 2010 8:23:03 AM by  Daniel Zobel [Product Manager]

2 Replies



PRTG should be able to calculate sizes above 10 TB correctly as the counters are 64 bit.

However, WMI is known to not stick to the rules now and then.

Please run the following query against your probe computer, using our WMI Tester tool:

SELECT * FROM Win32_LogicalDisk

and look for "FreeSpace" and "Size". Are these fields filled with plausible values?

Created on Jun 28, 2010 11:25:51 AM by  Volker Uffelmann [Paessler Support]

Last change on Jun 28, 2010 3:36:32 PM by  Daniel Zobel [Product Manager]



WMI Disk Free does have an issue with large volumes indeed. We'll fix that in one of the next versions.

However, if this volume runs on a > Vista/2008 system, you could try to use a WMI volume sensor instead.

Created on Jul 1, 2010 3:35:05 PM by  Volker Uffelmann [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.