Our PRTG Core is behind a firewall with multiple WAN links. Port-forwarding is configured on the firewall for remote probes to connect in to the core - and this is possible on any of the WAN IP addresses.

However, the probe can only be configured to connect to one of these addresses, from what I can tell.

What I'd like to be able to do is have multiple core server IPs configured in the probe and the probe would cycle through them in case one is down. It would always be connecting to the same core, just via a different path.

Is this possible?

Article Comments

Hello alexism,
thank you for your KB-Post.

A Remote Probe can only have a single destination Core Server IP or DNS Address, there's no way to configure multiple Addresses for the probe to connect.

Best Regards,
Luciano Lingnau [Paessler Support]


Apr, 2017 - Permalink

Ok, thanks - can we raise this as a feature request?

In the meantime we're looking at workarounds, such as using bouncer as an intermediary to round-robin the connections (https://github.com/ggrandes/bouncer).


Apr, 2017 - Permalink

I've talked to the responsible developers, this is not on our roadmap I'm afraid. The number of customers looking for this kind of capability is very low and we would have to make fundamental changes in PRTG to implement this, so we don't see this implementation coming anytime soon. You can read more about how we handle feature requests here:

As for the intermediate round-robin bouncer: We strongly advice against this, this could cause unforeseen consequences to the Core/Probe connection. If this is vital to your business, you could try:

  1. Use a scheduled task to confirm that the Core Server is continuously accessible.
  2. If the used IP becomes unavailable:
    1. Stop the Probe Service
    2. Change the core server address in the registry
    3. Start the Probe Service again

Best Regards,
Luciano Lingnau [Paessler Support]


Apr, 2017 - Permalink

Thanks for the suggestion, we'll set up a powershell script to do that. Can you point me to the registry key we'd need to change for this?


Apr, 2017 - Permalink

Sure thing!

This is the path:

HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\Paessler\PRTG Network Monitor\Probe

The relevant keys used to define the address of the core server are:

Windows Registry Editor Version 5.00

[HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\Paessler\PRTG Network Monitor\Probe]
"Server"="server.domain.tld"
"ServerPort"="23560"

Also, you will see some keys like:

"Server1"=""
"ServerPort1"=""
"Server2"=""
"ServerPort2"=""
"Server3"=""
"ServerPort3"=""
"Server4"=""
"ServerPort4"=""
"Server5"=""
"ServerPort5"=""

You may feel tempted to use these. DON'T. There are only for PRTG Clusters, just "leave them be" (unset).


Apr, 2017 - Permalink