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From: "Eggert, Lars" <lars@netapp.com>
To: Ivan Voras <ivoras@freebsd.org>
Subject: Re: Problems with two interfaces on the same subnet?
Thread-Topic: Problems with two interfaces on the same subnet?
Thread-Index: AQHOCUb6Tp99D1R3iECoMLZWzmGEXph3AyuA
Date: Tue, 12 Feb 2013 17:38:40 +0000
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X-List-Received-Date: Tue, 12 Feb 2013 17:38:44 -0000

Hi,

On Feb 12, 2013, at 9:32, Ivan Voras <ivoras@freebsd.org> wrote:
> I have a machine with two interfaces, igb2 and igb3 on the same subnet
> but with different IP addresses, e.g. igb2 has 192.168.1.221, igb3 has
> 192.168.1.222. Firstly, is there anything which would preclude this from
> working? As I see it, these are two different MAC addresses and to the
> outside world should look as two different hosts, right?

depends on what you mean by "work". There will only be one default route ou=
t of the box.

> * With both NICs connected to different switches, everything appears to
> work, BUT, if igb2 cable is disconnected, pings to igb3 simply stop,
> even though its cable *is* still connected.

This sounds like your default route is going via igb2.

You can make this work with ipfw rules (and I guess also setfib, although I=
 have not tried that.)

Lars