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Sensor Status History starts with unknown state




when we create a report with the sensor status history then it always starts with an unknown state. Is it possible to change this behavior? The interval for polling the sensor is set to 60 seconds, so the unknown state is always beginning with the chosen report start time until the first polling time during the report period.

If I set the start time of the report to an earlier date the unknown period is shown as "uptime" and again the first seconds of the new report will appear as unknown.

Thank you

prtg-sensor-history report unknown-status

Created on Sep 12, 2016 11:32:52 AM

Last change on Sep 13, 2016 1:14:40 PM by  Luciano Lingnau [Paessler]

5 Replies

Accepted Answer



Hello there,
we appreciate your feedback.

You're referring to this, correct? (Example: )

Report Time Span:12.09.2016 14:58:00 - 13.09.2016 14:58:00
Sensor Type:Ping (5 m Interval)
StatusDate Time
Unknown12.09.2016 14:58:00 − 12.09.2016 14:58:48(=48 s)
Up12.09.2016 14:58:48 − 13.09.2016 14:53:48(=23 h 55 m)

This happens because the routine that calculates the History Status doesn't "filter" these first 48 seconds (in this example) prior to the first scanning of the sensor(in other words, there are no readings stored in the database for the period of 14:58:00 - 14:58:48). This time is technically "unknown" as there are no readings for it.

I will raise awareness to this in development, but can't confirm at this time whenever we'll change this behavior in the future, but there's no configuration/setting to modify this behavior in the current (16.3.25) PRTG Version.

New: Edit (21/09/2016)
I've received confirmation from development that there's no plan to modify this behavior at the moment, as it would not be a straightforward change and may have unwanted side effects which we'd like to avoid.

Best Regards,
Luciano Lingnau [Paessler Support]

Created on Sep 13, 2016 1:14:30 PM by  Luciano Lingnau [Paessler]

Last change on Sep 21, 2016 11:37:25 AM by  Luciano Lingnau [Paessler]



I would like to take up the subject again. I understand that it requires the status Unknown, but it would be very nice to be able to hide it in the report template.

Created on Jun 2, 2020 4:37:30 PM



Hi there,

This behavior cannot be changes now and therefore I would recommend to change the report period to "hide" the state. As further step, you can also create a feature request. If this feature request is voted from enough users vote for the feature to hide the unknown status, we will add it to our pipeline.

Created on Jun 3, 2020 6:22:54 AM by  Moritz Heller [Paessler Support]



Hello there, relate to Sensor Status History, Can I generate the sensor status history using API? I've tried using historic data API but I cannot get the sensor status history data.

Thank You

Created on May 18, 2022 2:55:40 AM



Hi there,

there is no Sensor Status history. An alternative would be to use the "Log" tab of a Sensor to receive the status from the period ago. However, in this view "Up" status is only logged if another status has ended and the Sensor is "Up" again. If no status was logged, the Sensor is "up" all the time.

Created on May 23, 2022 5:54:09 AM by  Moritz Heller [Paessler Support]

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