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Inverted Sensors



Hi there,

I would like to request the feature of inverting individual sensors.

We have a few cases where being able to selectively invert sensors is important, in particular:

  • DR servers need to be running, but not their services under normal operations,
  • Individual switch ports are disconnected and should alert when something connects to it

Cheers, Neil

feature-request inverse prtg

Created on Dec 1, 2014 4:02:49 AM

2 Replies



In the sensor channel settings, you can define upper or lower limits for warning and error states. This should enable you to define the condition for status changes according to your needs, e.g. for switch ports, you could set the upper error limit to something slightly larger than 0 to have the sensor enter error state whenever traffic is seen on the interface.

Created on Dec 2, 2014 1:15:49 PM



You can create a Factory Sensor to monitor e.g. a Ping Sensor of your DR Server and a Service Sensor of the same.

You can e.g. this for the Error Handling > Use Custom Formula:

status(sensorIDPingSensor) AND NOT status(sensorIDServiceSensor)

The factory sensor will be up if the Ping is up and the Service Sensor is down.

Created on Dec 2, 2014 3:19:21 PM by  Felix Saure [Paessler Support]

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.