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The probe GID of my remote probe changed. What is the reason?



After updating to PRTG 20.1.55, I noticed that the probe GIDs I manually assigned to my remote probes have changed. What is the reason for this change and does it affect my monitoring?

probe-gid prtg prtg-administration-tool

Created on Sep 19, 2019 11:42:37 AM by  Maike Guba [Paessler Support] (2,404) 2 1

Last change on Jan 20, 2020 7:29:27 AM by  Maike Guba [Paessler Support] (2,404) 2 1

1 Reply

Accepted Answer



This article applies as of PRTG 20.1.55

Reasons for the change

In PRTG versions prior to 20.1.55, we did not validate a probe’s global identifier (GID). As a result, the Probe GID you could manually assign to a remote probe or a mini probe via the PRTG Administration Tool could be any string, for example, {johnqpublic-company}.

As of PRTG 20.1.55, GIDs like {johnqpublic-company} are invalid. The GIDs must have the correct format to make probe connections more reliable. A valid GID can have one of the following formats:

  • {3D1E94F6-6481-4B75-B3F5-A669EE98DA6F}
  • 3D1E94F6-6481-4B75-B3F5-A669EE98DA6F

If you manually changed a remote probe’s GID to a string like {johnqpublic-company}, PRTG automatically generates a new, valid GID for the remote probe the next time it connects to the PRTG core server.
Therefore, the change does not affect your remote probe configuration and monitoring setup. You can continue your monitoring as usual.

If you manually changed a mini probe’s GID to a string like {johnqpublic-company}, you need to manually update the invalid GID to a valid GID in the correct format. Otherwise, the mini probe will no longer be able to connect to the PRTG core server because it cannot update automatically.

Additional changes

We also implemented some changes to the functionalities of the PRTG Administration Tool:

  • It is still possible to edit a probe GID using the PRTG Administration Tool. However, you can no longer assign an invalid GID to a probe. Entering an invalid GID results in an error message and the previous, valid GID is restored.
  • We added a Generate new GID… button on the Probe Settings for Core Connection tab.

Important notice: Generating a new probe GID is a critical action. It will cause the remote probe or the mini probe, for example, to be detected as a new probe the next time it connects to the PRTG core server. As a result, you have to approve the probe again. Furthermore, if you wish to continue monitoring your network with the same device and sensor setup as before, you need to manually move your monitoring objects to the new probe.

Keep in mind that this also applies when downgrading to a PRTG version prior to 20.1.55. When you use a previous probe configuration that still contains the former probe GIDs, PRTG detects remote probes or mini probes as new probes the next time they connect to the PRTG core server.

Created on Sep 19, 2019 11:47:37 AM by  Maike Guba [Paessler Support] (2,404) 2 1

Last change on Jan 27, 2020 2:14:24 PM by  Maike Guba [Paessler Support] (2,404) 2 1

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.