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Why go through an Unknown state instead of directly Up?



After a sensor leaves Down state, the ping sensor goes through an Unknown state and then Up.

Why go through an unknown state instead of directly up?

In what case does the sensor become unknown even if the probe is running?

probe sensor sensors status unknown

Created on Apr 1, 2020 6:51:43 AM

1 Reply




Usually the sensor should go directly Up again, if the scan was successful. The unknown state means that PRTG has no information about the sensor at that time.There can be various reasons why sensors show an Unknown status. For example the sensor has not received any data yet or there is an error in the (network) communication.

Created on Apr 1, 2020 11:48:00 AM by  Timo Dambach [Paessler Support]

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