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What are conditions for PRTG Probe Service to restart automatically




Periodically PRTG Probe Service seems to restart itself based on certain conditions. Atleast:

"Trying to restart probe. Reason: more than 50 unresponsive scan threads" is one of these.

Are there any other conditions when this is triggered?

br, Olli Jokinen

probe prtg restart service

Created on Aug 4, 2010 6:00:19 AM

5 Replies

Accepted Answer



In essence, the only situations that cause the probe service to restart are:

  • more than 50 unresponsive scan threads
  • all WMI connections being in an identical error state

And, of course, restarting the service manually.

Created on Aug 5, 2010 3:08:11 PM by  Patrick Hutter [Paessler Support] (7,225) 3 3



Thanks for the info,

Additionally is this another condition as well?

"Trying to restart probe. Reason: connection unresponsive for more than 60 seconds."

Since this seems to have the same effect...

Created on Aug 6, 2010 10:04:04 AM



The message "connection unresponsive for more than 60 seconds" is one of the ways a stalled probe<>core SSL connection can materialize.

Created on Aug 6, 2010 10:21:51 AM by  Dirk Paessler [Founder Paessler AG] (11,025) 3 6



Should this be the case when data is cached on the probe until the core is back online?

It would be beneficial to understand all possible conditions when to expect such problems.

Created on Sep 2, 2010 7:40:53 PM



Yes, a probe might also be restarted even if it has cached data, due to a "not available" Core Server. Because it is surely better to have a working/monitoring probe rather than a not-scanning one, which has a bit of cached data.

Created on Sep 3, 2010 12:41:14 PM by  Torsten Lindner [Paessler Support]

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