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Uptime calculation question



In a report, we can see uptime values as follows:

Sensor A: 100 % [26d18h54m44s]
Sensor B: 100 % [26d18h59m43s]

Both sensors are in the same report, for exactly the same date range, and has been completely up and running within that date range with no Pause intervals (no entries in the Log).

But there is a difference of about 5 minutes between the 2 uptime hours. What could account for this discrepancy?

calculation report uptime

Created on Sep 28, 2011 9:38:23 AM

Last change on Sep 28, 2011 12:24:57 PM by  Dirk Paessler [Founder Paessler AG] (11,025) 3 6

1 Reply

Accepted Answer



The two key question are:

  • What intervals do these sensors run?
  • Have the Core server or the probe been started/stoppped/rebooted within the date range of the report (probe and core server are sometimes restarted automatically by PRTG when it descoveres that stability may be affected)

If the interval is 5 minutes then the explanation is easy: The reports covers one more interval for the second sensor. The missing interval of the second sensor was likely just beyond the end of the date range of the report.

A core/probe restart may also have the effect that intervals are not in sync.

Created on Sep 28, 2011 12:28:24 PM by  Dirk Paessler [Founder Paessler AG] (11,025) 3 6

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