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Date: Sun, 11 May 2008 20:52:13 +0100
From: "Jay L. T. Cornwall" <jay@jcornwall.me.uk>
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To: "H.fazaeli" <fazaeli@sepehrs.com>
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Cc: freebsd-net@freebsd.org
Subject: Re: if_bridge with two subnets
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H.fazaeli wrote:

> The bridge works as it should: It receives packets from
> XX.XX.XXX.YYY on the interface connected to the switch, and
> forwards them on the interface connected to the gateway.
> 
> The problem is that forwarding between subnets is the responsibility
> of your switch. The switch does its job, but since the two clients are
> not on the same IP subnet, they can not reach each other w/o the help of
> an intermediate router.

Perhaps I am mixing up two separate networking concepts.

On a machine configured to act as a gateway, I would expect a single 
interface with more than one subnet to route packets correctly across 
those subnets. That may not be how it works in practice.

If it does not work, I would question why not. If it does work then I 
would expect the same behaviour on each of a bridge's constituent 
interfaces?

-- 
Jay L. T. Cornwall
http://www.jcornwall.me.uk/