I am assuming these are two separate servers. If so they just have to be on a LAN connected together and the routing has to be setup at each server. They do not have to be registered. In this way they operate as private nodes. Of course anything that needs the Internet will not work. Here is info on doing the routing. It applies equally to any Allstar node - Acid, BBB, RPi2, etc.

http://www.crompton.com/hamradio/BeagleBoneBlackAllstar/multi-server%20howto.pdf

73 Doug
WA3DSP
http://www.crompton.com/hamradio

> From: kk6ecm@gmail.com
> To: app_rpt-users@ohnosec.org
> Date: Thu, 2 Jul 2015 22:28:17 -0700
> Subject: [App_rpt-users] How to Hardwire Two Nodes in One APP_RPT Server
>
> I'm looking for information on how to "hardwire" link two nodes together in
> my server. One node is full-duplex repeater and the other is a half-duplex
> RF link to a second repeater that has full Allstar control on both the
> repeater and the link. They are located at a remote site, with no internet
> connection after install. I'm sure there are other things I'm missing, but
> this will enable me to experiment with final configuration combinations.
>
> Thanks,
> Bob
> kk6ecm
>
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