[lug] forcing certain services to use eth1 instead of eth0

[Sean Reifschneider]

On Tue, Jan 03, 2006 at 05:01:31PM -0700, Nate Duehr wrote:
>Ah, so the machine had an eth0 on a network, and eth1 was added on that 
>same network?
>
>Should just work.

Maybe in a perfect world, but that is not at all the case.  Outgoing
packets are going to use the default route, which is (unless you do
something fancy) going to be just one of your interfaces.  The traffic, if
it is responses to external incoming connections, is probably going to have
the right local address on it.

I agree with Kevin that setting up a different network range on the net
interface is probably going to be the most robust in the long term and
easiest to deal with.  In theory you can do what you want using MARK and
iproute2, but in my experience this setup can be difficult to manage and
understand, aided partly by extremely poor iproute2 documentation, and
therefore can be fragile and hard to debug.

Thanks,
Sean
-- 
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Sean Reifschneider, Member of Technical Staff <jafo at tummy.com>
tummy.com, ltd. - Linux Consulting since 1995: Ask me about High Availability