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Randomely Failing Sensors



So out of the blue, our sensors are reporting false values. WMI Disk Space sensors are reporting 0% free space, pings are timing out, WMI service sensors are reporting services to not be running, it's just chaos. I have tried increased the scanning intervals and doubled the amount of probes. I have also gone through the logs and find nothing out of the ordinary. To PRTG, the sensors are functioning just fine because they are returning values but those values are relative zeros. There are about 100 failing sensors with little or no relation to each other.

No changes have been made to PRTG or the host machines. All the hosts are physicals and don't get any automatic updates. I want to go as far to say our setup has not changed in any way.

We are running version

What can cause this?

failing probe prtg random sensors wmi

Created on May 13, 2013 12:41:25 PM

1 Reply




Could you please try updating to the newest version and see if this resolves the issue? We had a few issues with null values being reported and the update should take care of it. If you continue having issues, please send a ticket in to [email protected] and include your logs.

PRTG Data Storage

Created on May 13, 2013 6:03:00 PM by  Greg Campion [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.