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From: Joe Greco <jgreco@brasil.moneng.mei.com>
Message-Id: <199608222353.SAA25487@brasil.moneng.mei.com>
Subject: Re: A questionon on IP routing
To: luigi@labinfo.iet.unipi.it (Luigi Rizzo)
Date: Thu, 22 Aug 1996 18:53:31 -0500 (CDT)
Cc: hackers@FreeBSD.org
In-Reply-To: <199608222158.XAA01449@labinfo.iet.unipi.it> from "Luigi Rizzo" at Aug 22, 96 11:58:49 pm
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> Hi,
> 
> for some test I would like to do, I need to make two systems, on
> the same subnet, say A and B, talk to each other with IP traffic
> going through a router R which is far away (several hops) from both
> A and B.  Is there any chance to achieve this behaviour in general,
> and in particular if A, B and possibly R run some version of FreeBSD ?

It would be difficult, very difficult.

If you have two links off of your subnet, it might be somewhat easier.  If
not, you need a router that can route based on source address.

If you have two links off your subnet (and two routers), I would suspect
that you can set the routing tables on each machine to point to a 
respective router for the other host, that router (and probably the
intermediates) would do the same, until you reached R.  It would be ugly,
at least in general.

... JG