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How to "Batch-Update" SNMP Disk free Sensor after reformat




we monitor our Citrix-Workers with PRTG. After reinstalling the Master, the hdd c: was reformated via MECM and PRTG is showing a missing item since its serial number has changed.

How can we update all Workers in PRTG without having to adjust every single server manually (>200) with the new serial of drive c:\?

Any help is much appreciated!

Thanks in advance


diskfreesensor prtg snmp

Created on Jul 27, 2021 9:14:37 AM

3 Replies



Hi there,

I'm afraid that there is no automatic way to change / re-discover the serial numbers of these hard drives. Possibly the easiest way would be to pause the old sensors and to discover the sensors anew using the auto-discovery. This would keep the sensor history for later reporting purposes.

If you click on the small lock symbol in the settings of each disk, you can also manually enter the number. Be aware that this needs to be accurate so that PRTG can identify the disks.

Kind regards,
Felix Saure, Tech Support Team

Created on Jul 30, 2021 10:11:47 AM by  Felix Saure [Paessler Support]



Hi, thanks for your answer. Then it is as I feared and I have to individually touch every single server (now 200, when we finished it will be 500+) when we recreate the image from scratch...

Can I somehow delete a single sensor (disk sensor) on all objects in a group so that I can batch-delete and then rescan?

And: Would a WMI-Sensor for disk space be more flexible in this regard?

Many thanks again


Created on Jul 30, 2021 12:37:40 PM



Hi Daniel,

If these devices / sensors do not have a custom tag assigned, the best approach would be to create a list of sensors and sort it by type Sensors > By Type > S > SNMP Disk Free. You can then click the column name and sport it by Probe / Group Name to then use the Multi Edit function via the GUI.

I understand that this is cumbersome as changing the serial number is not an every day task which PRTG needs to regularly adopt to.

We recommend to not go for so many WMI sensors, as it's a very sluggish procedure and a bottleneck in terms of performance. For the specific disks, the name as well as the device ID are considered. You can get the values via this command:

    DriveType, DeviceID, FreeSpace, Size, VolumeName

I cannot yet tell if this will change in the future, but you can follow these steps to request a new feature / improvement for future versions of our software: Feature Request.

Kind regards,
Felix Saure, Tech Support Team

Created on Aug 2, 2021 5:25:45 AM by  Felix Saure [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.