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Cluster IP Addresses on server with multiple network cards



Hello and please sorry my english mistakes.

I installed PRTG Version as cluster in two servers with multiples network cards. For the installation and cluster setup, always I used the IP addresses of the network cards connected to the internal network. However, when going to activated the standby (secondary) prtg I saw it used the external ip address.

How to change the ip addresses used by the cluster PRTG in order to use the internal ip address and not the ip addresses of my external network? Please, take note that using the external network means open the port 23570 to all the Internet (I can't setup a rule there to restrict the ip addresses allowed).

Thank you,


cluster ip prtg

Created on Jul 20, 2011 3:59:27 PM

3 Replies



the cluster nodes are in two different locations separated by WAN and behind firewall?

Created on Jul 22, 2011 11:11:56 AM by  Aurelio Lombardi [Paessler Support]



Hello Aurelio. No, they don't. Both server are in the same location. Each server has two network cards (NIC). One NIC is connected to the internal network, the second NIC to he external network. The external NIC has activated a firewall (Basic firewall of Windows's RRAS). The internal NIC hasn't any firewall activated. That's why when I installed the secondary PRTG and setup the ip address for the primary RPTG for clustering, I wrote the internal IP address of the primary PRTG, because between internal NICs there is no firewall. However, even I wrote the internal ip address, prtg "just tooks" the external ip address forcing me to open the port 23570 at the firewall. I don't like to left open that port for whole Internet. Unfotunately, the RRAS's firewall can't restrict traffic from specifuc ip address. That's why I need to setup PRTG clustering traffic between internal NIC's, and not trough the external ones. Thank you for your help. Fernando.

Created on Jul 22, 2011 8:07:17 PM




please send the Logs(system) folder from both servers to

[email protected]

with a reference to the KB article.

You can find the same under

XP/2003: C:\Documents and Settings\All Users\Application Data\Paessler\PRTG Network Monitor\V8\Logs (System) Vista/2008: C:\ProgramData\Paessler\PRTG Network Monitor\V8\Logs (System)

Created on Aug 2, 2011 11:10:11 AM by  Aurelio Lombardi [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.