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Dynamic LimitMaxError in custom script



Hi, I am using a custom sensor to monitor snapshots in our VCenter. On the first scan I am getting the right error message with the names of the VMs, but the other messages do not update with the updated ones.

Please advise.

custom-sensor prtg ps1 snapshot

Created on Jan 19, 2021 10:22:12 AM

5 Replies



Hello Michael,

Thank you for your message.

Regarding what you are trying to achieve, I'm afraid that it's not possible to update the limits of a sensor after its creation via the custom script. Indeed, the limits are only applied during the creation of the channels and ignored afterwards.

Therefore, to modify the limits of the sensors, I invite you to use the API of PRTG. Here is the corresponding manual: https://www.paessler.com/manuals/prtg/object_manipulation#channel_properties.

If you have questions, let us know.


Created on Jan 20, 2021 6:59:46 AM by  Florian Lesage [Paessler Support]

Last change on Jan 20, 2021 7:00:13 AM by  Florian Lesage [Paessler Support]




Ok , thanks!

Created on Jan 20, 2021 7:11:44 AM



Could you please suggest a script to check VMware snapshots? I found a sensor in the Sensor Hub, but it does not appear to work.

Created on Jan 20, 2021 7:32:49 AM



What sensor do you use to execute the script? Are all the requirements mentioned in the script fulfilled ? What error message do you get in PRTG? Can you please execute the script manually on the PRTG server and check what is the output.

I also found a KB article regarding VMware snapshots monitoring, here it is: https://kb.paessler.com/en/topic/29313-vmware-snapshots


Created on Jan 20, 2021 8:41:29 AM by  Florian Lesage [Paessler Support]



Script works on local VM , but on PRTG logs it gives "(invalid json.). (code pe231)" error. I will try the one in the article later.


Created on Jan 20, 2021 8:48:46 AM

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