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The PRTG downtime basics



I do not understand the basics about downtime. How is downtime (for snmp interface traffic monitoring) calculated? I mean I think I get fake information for snmp sensor about downtime. PRTG requests snmp information via snmp and what should happen to show a downtime? SNMP reply with some "down" information? Or PRTG calculates no counter change since last check or something else?

basics downtime prtg

Created on May 7, 2011 4:39:32 PM

1 Reply




the calculation of downtime is the same for every sensor. Downtime is the time between at least two consecutive failed scans of a sensor (i.e. scans with the sensor going and staying in DOWN state). Then the time between these two scans (or if more, the time between the first and the last scan) is accounted as downtime.
So first of all this downtime refers to the sensor itself. Not necessarily to the target (SNMP Traffic Sensors don't get downtime information from a switch or similar).

Best regards.

Created on May 9, 2011 1:34:03 PM by  Torsten Lindner [Paessler Support]

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