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False alerts




I am evaluating PRTG Network monitoring and it seems really good except for the false alerts. We get a lot of "Connection could not be established (Port Error : RPC Server not accessible. -) (code: PE015)" and five minutes later it is fine. We see this specially at night when the backups are running. I set the scanning interval to 5 minutes and Windows Compatibility Options to WMI only.

I have also seen several alerts like this: "Sensor stopped due to WMI lockup. Can be restarted with pause and resume. If not, please try restarting the probe. (code: PE055)".

What else can I do to avoid false alerts?

Also, how can we stop the alerts about sensors paused by dependency and resume by dependency? The way I see it, the reason you set up dependencies is to avoid a flood of down alerts, but then you get a flood of pause by dependencies alerts, so what is the point?



false-alerts paused-by-dependencies rpc-server

Created on Aug 12, 2013 3:59:16 PM

2 Replies




thank you very much for your KB-Post. The first thing, that actually you already are doing, is using longer scanning intervals, but also please check, that the scanning interval is 5 minutes then using the "Sensors"->"Cross Reference"-Table, especially on those WMI Vital System Data sensors.
Maybe also remove any WMI sensors that are not "really necessary" (and only add them in certain debug-situations), or pause them. These two actions should help already. Please also make sure that the WMI Sensors inherit the scanning interval set on higher level, you can do this with the "Sensors"->"Cross Reference"-Tables, which can be sorted after the Interval-column.
The next thing could then indeed be deploying Remote Probes, maybe if the targets are grouped in subnets, or similar, then put a Remote Probe in each of these subnets. The final last resort, would be considering using SNMP to monitor the Windows Hosts, with something like SNMP Informant, where the free version of it, already covers most basic WMI Counters.

best regards

Created on Aug 13, 2013 12:44:37 PM by  Torsten Lindner [Paessler Support]



Thanks for the reply. I think I found the problem. The server where the remote probe is installed has two NICs and looking at the Probe administrator tool, it was defaulting to use the wrong NIC. I changed it now and will see how it goes over a few days, but looking better already.

Thanks Gus

Created on Aug 14, 2013 4:49:17 PM

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