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Can i reverse the status of a senor?



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As stated above can i reverse the status of a certain sensor? we have a back up MPLS Circuit and currently it is configure with HSRP as Active/Standby. i want to receive alert when this link came up. is it possible? Thanks

custom-sensor prtg sensor

Created on Nov 23, 2015 9:25:56 AM by  nezky (20) 1

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Dear Nezky

With the help of the sensor factory, a sensor status can be reversed. To do so, create a factor sensor. Set the factory error handling to "Use custom formula".

This is an example in which we mirror the state of the sensor with the sensor ID 2123. There are different ways to write the inversion formula for the status, one is


The strange number "10000" is a result of the internally used fixpoint format. A sensor status can only be 0 (up) or 10000 (down.)

In addition to the status formula, the sensor also needs a channel formula. You could just mirror any source channel, for example


The data channel is just for having a channel, the important thing is the inverted status. If you put a state trigger on this sensor, it alerts when the factory sensor turns red. It will do so when the source sensor is up. The source sensor could be ping sensor.

For optimal performance, please set the factory sensor to the same scanning interval as the source sensor.

Created on Nov 23, 2015 6:03:04 PM by  Arne Seifert [Paessler Support]

Last change on Nov 23, 2015 6:03:37 PM by  Arne Seifert [Paessler Support]

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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.