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Errors and warnings using regular expression




So I am trying to configure some monitoring for a device that uses dBm as its measurement. So far I have added extended processing to pull the value from the "device message" and make it its own value using the regular expression (-\d+\.\d+) to extract a numeric value.

Now what I need to do is create warnings and error thresholds based on that reading. So -50 to -64 dBm is fine -65 to -74 dBm is a warning and 75+ dBm is an error

The sensor is an SNMP Custom String, the question is does anyone know how I can set the warnings as mentioned above somehow?

Thanks guys

code custom-script-exe help prtg reporting snmp

Created on Feb 13, 2020 10:59:53 AM

3 Replies



Hi there,

you would need to activate the option "Extract Number Using Regular Expression", so you're able to extract the values as float.

Here you'll find additional information.

If this did not help, please provide me with the following screenshots via email to "[email protected]", please add "PAE1311739" in the title:

- Screenshot of the sensor's "Overview" tab
- Screenshot of the sensor's "Log" tab
- Screenshot of the sensor's "Settings" tab

Thank you in advance!

Kind regards,
Andreas Günther
Tech Support, Paessler AG

[email protected]

Created on Feb 14, 2020 12:31:22 PM by  Andreas Günther [Paessler Support]



Hey guys, I am trying to achieve exact same thing. The message I am getting is "16asu (-81dBm)" And using the expression (-\d+\.\d+)

Unfortunately not getting the desired value "-81'

Created on May 5, 2022 11:41:26 PM



have you tried using the regex "(-\d+\d+)" - without quotation marks. For testing regex I can recommend the site https://regex101.com/.

Created on May 9, 2022 4:34:31 PM by  Timo Dambach [Paessler Support]

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