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How to use Sensor Factory to only give error when two sensors are in error?



I am using the IMAP Round Trip sensor to monitor our outbound email sending. I have 2 sensors set up, one using GMail and one using AOL. Currently if either one is in error I get notified even if the other is working. AOL is flaky at times and is usually the one erroring out, but GMail is not 100% accurate either, hence using both sensors to monitor outbound.

I would like to set up a Sensor Factory sensor that monitors both IMAP sensors and only alerts me if both of them are in error. I have tried adding the downtime channels of each and checking if it's over 0 but I never get any data on my sensor.

Is there any way to have an alert trigger only if two sensors are in error?

alerts multiple-sensors sensor-factory

Created on Oct 20, 2011 7:15:26 PM

4 Replies




please take a look at the

Define Sensor Status—status() Function

section of


status(2031) AND status(2044)

This will change the factory sensor to a Down status if both sensors, with IDs 2031 and 2044 , are Down . Otherwise the factory sensor will show an OK status.

Created on Oct 21, 2011 6:53:29 AM by  Aurelio Lombardi [Paessler Support]



Thank you. That looks to be a new feature as of PRTG 9. I just updated yesterday and it's there now.

Works perfectly for my situation.

Thank you.

Created on Oct 21, 2011 4:18:29 PM



I have a Sensor Factory of 8 Sensors. I want the Factory goes on warn if 2 sensors go down. And i want the Factory goes on error if 3 or more goes down. Any ideas?

Created on Mar 23, 2016 2:26:41 PM



Hi Capo,

This will work best with the new Busniess Process Sensor. You can add all eight sensors and define the percentage of failing sensors to either set the sensor into a warning, or into an error status.

This is also described in this article.

Best regards, Felix

Created on Mar 24, 2016 6:33:07 AM by  Felix Saure [Paessler Support]

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