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Is there an automatic reset/clear on an acknowledgement?



When I acknowledge a "down" sensor and add notes, it seems to reset and show up red again, in the Alarms screen after a while, cleared of the acknowledgement and notes. Is there a default reset time? version 8.2

acknowledge alarms prtg8

Created on Jan 18, 2011 7:38:26 PM

5 Replies



did you restart the probe or the server by any chance?

That would cause the alarm to become active again.

Created on Jan 19, 2011 9:46:17 AM by  Aurelio Lombardi [Paessler Support]



Hi there
Do acknowledgments and notes become clear each time the local/remote probe is restarted? (what about the core server?)
If so, what is the logic?
And how can i prevent it?
Because then all those sensors have to be ACK again with related note, and many of them may have been forgotten!
Thanks a lot

Created on Jan 24, 2021 6:31:27 AM




an alarm will be acknowledged as long as:

  • the sensor goes into UP state again
  • the sensor is paused for what-ever reason
  • the PRTG Core Server or Probe service is restarted

    The sensor results could have changed during the reboot. To ensure you are receiving alerts for every new issue, the sensor needs to be resumed after a restart of PRTG. This behavior cannot be changed.

Created on Jan 26, 2021 9:13:23 AM by  Timo Dambach [Paessler Support]

Last change on Jan 26, 2021 9:13:31 AM by  Timo Dambach [Paessler Support]



@Timo Dambach That does not appear to be entirely accurate. A sensor that is acknowledged "indefinitely" does not come out of acknowledged state upon reboot.

Created on Feb 4, 2021 7:14:26 PM



Hey John,

Sorry, yes you are right: It's not entirely accurate. A sensor will be acknowledged as long as the graph cache needs to be re-calculated. If you reboot PRTG, I would expect the graphs to be recalculated as well. However this might not always be the case as it depends on multiple factors like how long the PRTG server was offline, or (if the probe service is still running) how much data was gathered during the downtime of the Core Service etc. So if your PRTG server reboots quickly and there's not a long downtime, sensors might indeed still be acknowledged after restarting.

Created on Feb 8, 2021 10:36:17 AM by  Timo Dambach [Paessler Support]

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