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Failover cluster



In System requirements for PRTG it is said that PRTG cluster is not recommended for 5000 licence thus meaning safe spot for clustering is 2500 sensors. What are the possible problems if I'd try to make failover cluster for 5000 sensors, is it just the performance issues which could be fixed by upgrading HW, or is there some other problems I could encounter, that can't be fixed just by system upgrade? It's just that I have bought several 5000 sensor licences to split my one XL licence for failover cluster purposes, and I want to know how much sensor space of those licences I can use for safe clustering.

clustering failover failovercluster prtg

Created on Jun 30, 2020 1:34:02 PM

3 Replies




Yes, that is correct. We recommend to stay below 2500 sensors in a cluster for the best performance. However we don't set a hard sensor limit. You can deploy as many sensors you want, but keep in mind that you may have performance issues if you have too many sensors. We put the mark to 2500 sensors according to our experience in other customers installation. Up to this number, a cluster should work flawlessly.

It may be possible to use more than 2500 Sensors without any issues, but we cannot guarantee this, as the performance depends on multiple factors like the hardware that you are using, your scanning intervals and of the type of sensors you use. For instance 2,000 ping sensors don't consume as much performance as 2,000 VMware sensors do.
You have to look at your settings, especially to the probe sensors itself. If you get a delay or falling system health, then this should be the first indication that you should start changing settings or distributing the sensors to multiple servers.

Please also have a look at the following articles for configuration recommendations:

- How to Speed Up PRTG
- If you are using VM's: Checklist for Running PRTG on VMware

Kind Regards,
Timo Dambach
Paessler Tech Support

Created on Jul 1, 2020 7:32:13 AM by  Timo Dambach [Paessler Support]



Thank you for the information. For testing purposes I had server with 3500 different sensors and I didn't see any performance issues, plus the system health was at 99%. So I thought maybe I could use my PRTG 5000 licences fully.

Created on Jul 1, 2020 7:43:56 AM



If you don't see any performance issues, your PRTG server seems to be already well configured :)
Feel free to try using 5000 sensors. If you start seeing issues you can still try adjusting settings or delete sensors again.

Created on Jul 1, 2020 8:13:37 AM by  Timo Dambach [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.