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All sensors on master node in cluster are unknown, unable to monitor



Hi Support,

I have one master node and one fail over node, on both nodes every sensor that is on my master node has no data for days now and all are in an unknown state. My Remote probes are fine though. just my master node that has the crucial systems in and need monitoring!

Please let me know once i have a log number and i will send you the log files, just to see if you can see anything i have done wrong or have missed??

I have done the latest update - my sensors were up for a couple of hours than gone again... I have restarted the service and the servers - this normally fixes it but hasn't.

Any help would be greatly appreciated. Thanks

clustered master prtg

Created on Sep 19, 2013 11:36:50 PM

1 Reply



This is most likely due to the fail safe that PRTG has built in. When there are too many time outs on a particular probe, the probe will restart a few times to try and solve the time out issues. If they persist, the Probe will shut down which will cause the unknown state of sensor that you are seeing.

Usually this can be resolved by looking in the probe logs and seeing which sensors are timing out and then moving some of these to another remote probe or possibly changing the scanning intervals to something higher to allow for the probe service to have more time to process the information. You can also send an email to [email protected] with your logs and reference this article and we can give you more specific recommendations.

Created on Sep 20, 2013 9:05:46 AM by  Greg Campion [Paessler Support]

Disclaimer: The information in the Paessler Knowledge Base comes without warranty of any kind. Use at your own risk. Before applying any instructions please exercise proper system administrator housekeeping. You must make sure that a proper backup of all your data is available.