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Notification question



Last week I was wondering (never came in my mind earlier) about the following.

When the time interval to check the status is set to e.g. 30 seconds with a sensor, and it goes to the status down then. What happens then ?

Does PRTG wait for the next interval set time (e.g. 30 seconds) and stay down during that 30 seconds, or what is the (auto) interval for a sensor when it has the status down ?

notification notifications status

Created on Dec 12, 2011 10:05:17 AM

3 Replies




in PRTG the scanning interval is always the same regardless of a sensors state.

best regards.

Created on Dec 12, 2011 3:52:23 PM by  Torsten Lindner [Paessler Support]



So, just to be sure I understand this right.

If a (http) sensor goes to the status down at 13:00 and the scanning interval is 15 minutes for that sensor and the http comes back ok at 13:01, the sensor will stay down untill 13:15 (next scanning interval) and I have a downtime of 15 minutes. (while it was actual 1 minute)...

Is there no way the check interval can be set to e.g. 1 minute when the status is down. and when it goes back up the normal interval is 15 minutes again (or what is confugured).

You will probably say, why don't set the sensor to 30 seconds. But sometimes this cannot be done because of the huge log-files it creates on some machines then.

Created on Dec 12, 2011 4:02:55 PM



The sensor will always run at 15 minutes scanning interval in this scenario, if this is only for one scan then you also will not have a downtime of 15 minutes, because downtimes are only accounted for at least two consecutive scans. Anyway, this is of course a matter of personal preference, but we think setting a scanning interval lower on an already down device is rather pointless, as it's already down, and a monitoring solution has the major objective of making aware of chances where devices could go down. So in fact, if there should be a smaller scanning interval, it should be when a sensor is up to 'faster' know when something goes down.

Created on Dec 12, 2011 6:17:01 PM by  Torsten Lindner [Paessler Support]

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