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Remote Probes and Communications Interruptions



If I have remote probes on servers and the internet (network) experiences an interruption, as long as those servers continue to function, will the remote probes buffer their information from their sensors?

And then once the network communications are restored, will they then update the core PRTG server with that data?

If this is correct, I would then expect some sort of a performance hit on the core server (as information was transferred back to the core server) depending on how many remote probes were offline and if they were not able to communicate over a sufficiently long period of time.


communications interruptions remote-probes

Created on Jul 3, 2012 6:13:44 PM

10 Replies




the Remote Probes do indeed continue their monitoring and cache the results should the connection to the core server break. But so far we did not encounter any huge spikes/load issues when Remote Probes reconnected to the Core (usually the Core has a higher load upon starting anyway, which lowers then later on in its runtime).

best regards.

Created on Jul 4, 2012 12:55:10 PM by  Torsten Lindner [Paessler Support]



Let's assume an Internet-link downtime happens on remote site.. for 2 days.

Is it right, that probe's cache (buffer) will store whole collected data and even persist if probe is rebooted/restarted? So the real gap in data will be only probe's downtime during it's restart..?

Is it true, that only hard drive's capacity limits the stored data buffer?

Created on Mar 31, 2015 7:12:57 PM

Last change on Apr 1, 2015 8:07:16 AM by  Torsten Lindner [Paessler Support]



This is not true. The Remote Probe only caches up to 500,000 results in the RAM. Reboots / Restarts will clear this cache.

Created on Apr 1, 2015 6:59:53 AM by  Torsten Lindner [Paessler Support]



About core server restart: Seems, remote probe's data was successfully uploaded in 2-3 minutes. I see no gaps in stats for core server downtime.

Created on Apr 1, 2015 7:52:57 AM



Core restarts should not impact the caching, only if the restart is due to a version update of PRTG (as the update of the Probe will then cause a Probe restart).

Created on Apr 1, 2015 7:56:05 AM by  Torsten Lindner [Paessler Support]



Here's my problem:

Remote site has a Remote Probe, a WAN channel and an UPS being monitored. Electricity downtimes usually exceed battery capacity.

Electricity outage affects some area around the site. WAN channel goes down somewhere in the middle of the route Probe<>Server.

Then battery capacity is depleted and probe is shut down. Cache is lost, no remote site's data collected for an outage duration.

Any plans to cache data on harddrive during core server's link failure? What solutions do I have now? Installing a cluster node on a remote site?

Created on Apr 1, 2015 8:34:04 AM



You could look into a cluster. However the Cluster will also shut down if the UPS runs empty. It might be better to get a more powerful UPS here.

Created on Apr 2, 2015 8:58:36 AM by  Torsten Lindner [Paessler Support]



I'm interrested in monitoring data, when WAN-link is off and UPS still alive. Cluster only?

Created on Apr 2, 2015 1:36:19 PM



Then it has to be a full installation of PRTG. Either Cluster or Stand alone.

Created on Apr 7, 2015 7:19:23 AM by  Torsten Lindner [Paessler Support]



Hope, one day you'll store cached data on HDD when probe shuts down.

Created on Apr 7, 2015 7:23:56 AM

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