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Backwards (?) Sensor



Hi! I bet this is a Newbie Quest but I don't no how to better describe my Problem: I have 10 different Sensor that I managed to successful read from a XML Source. It is about open Slots - the more available the better. If the Number goes to 0 it gets worse ...

I need a warning state when the capacity, say like in total there are 1.000 Slots, goes below 250 Slots. And an error if there are none left ...

Well, usually the Sensors in PRTG seem to work in the opposite direction.

How can I manage this? And how can I tell PRTG to show the Max amount of Slots I define?

Thanks for your help!

backward newbie sensor

Created on Sep 23, 2020 7:54:49 AM

3 Replies

Accepted Answer




Thank you for your message.

To configure the alerts, you can use the option Enable alerting based on limits in the corresponding channel settings of the sensors. Then, configure the thresholds under "Lower Warning Limit" & "Lower Error Limit" according to your needs.

The sensors should now trigger alerts when one of these limits is reached.

And how can I tell PRTG to show the Max amount of Slots I define?

I'm not sure to understand exactly what you would like to do. However, if this is related to limits you can use the "Upper {state} limit" fields to trigger an alert when the maximum value is reached.

Kind regards.

Created on Sep 23, 2020 11:30:12 AM by  Florian Lesage [Paessler Support]

Last change on Sep 23, 2020 11:30:55 AM by  Florian Lesage [Paessler Support]



I have opened a support ticket and sent you an email so we can exchange information more easily. However, if you didn't receive the email, here is its content:

Regarding the first point, you can configure the Lower Error Limit to 105, so the sensor will be in Error state when the value is equal or below 105.

​ Then, about the total number of slots you would like to display below the gauge, I'm afraid that there is no option to do that. PRTG automatically scales the maximum value based on the higher value plus 5%.

Created on Sep 23, 2020 12:28:23 PM by  Florian Lesage [Paessler Support]



Thanks Florian,

I guess that was the information I needed.

Keep on the good work!

Cheers, Anselm

Created on Sep 23, 2020 1:29:16 PM

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