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Date: Mon, 18 Feb 2008 16:05:02 -0600
From: Tom Judge <tom@tomjudge.com>
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To: Nick Barnes <Nick.Barnes@pobox.com>
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Cc: freebsd-net@freebsd.org, Bill Moran <wmoran@collaborativefusion.com>
Subject: Re: Multiple default routes on multihome host
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Nick Barnes wrote:
> At 2008-02-18 21:36:18+0000, Bill Moran writes:
<SNIP>
> 
> I would rather send packets from the P2 subnet addresses to the P2
> router, while the packets from the P1 subnet addresses keep going to
> the P1 router.
> 
> Apparently I can do this with some IPFW cunning, but that seems like
> overkill for what seems like it ought to be a common problem.


This is indeed a common problem, a question such as this gets asked 
every month or so on at least one the lists I am subscribed to.  In fact 
we do something along these lines at each of our offices to provide 
fault tolerant VPN connections to our data center and other offices.

However FreeBSD's routing table does not currently support policy 
routing without some help from the firewall.  The only way to achieve 
your goal is to use one of the firewalls (pf/ipfw/ipf) to do the policy 
routing for you.

The suggestions that you have received already seem to be exactly what 
you are looking for.


Tom J