sending requests to a virtual server when behind a proxy

[Louis Munro]

Hello,
I have a set of servers behind two FreeRADIUS servers configured to proxy and load balance to a pool of backend FR servers (2.26 both on the load balancers and backend).

I would like to send some requests to a different virtual server on the backend to authenticate our VPN requests separately from the regular Wireless authentications.

I can set the virtual server in the client definition (on the backend servers) and that seems to work well but when the requests are proxied through the load-balancers the client is the proxying server and so my virtual server config is not applied.

I could alway send those requests to a virtual server listening on a different port on the backend, but I would like to avoid that if there is a way.
That just adds more complexity and ports to manage in firewall and such.

Am I missing something obvious? 
I don’t think this could be done using dynamic clients since I can’t inspect the NAS-IP-Address there. 

Any other way that someone can think of? 

Your help is much appreciated,
--
Louis Munro
lmunro at inverse.ca  ::  www.inverse.ca 
+1.514.447.4918 x125  :: +1 (866) 353-6153 x125
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