Subject: Re: Multiple IP on a Single Interface
To: None <tech-net@netbsd.org>
From: James R Grinter <jrg@blodwen.demon.co.uk>
List: tech-net
Date: 06/01/2000 00:03:44
Hubert Feyrer <feyrer@rfhs8012.fh-regensburg.de> writes:
> On Wed, 31 May 2000, Seth Bradley Noble wrote:
> > Is there a way to have two different IP addresses (each going out
> > through a different router) on the same physical interface?
> 
> ifconfig le0 alias 1.2.3.4

Reading between the lines, I think that you are also wanting to be
able to direct the packet to different routers based upon those
different IP addresses. That makes it more interesting: there's no way
you can do this in the routing table. When I was doing something
similar, I used ipfilter's "fastroute" option to select my destination
interface.

Then I thought about your situation some more. I don't think fastroute
would be suitable even if you had multiple real interfaces, because
the system would not know where to send the packet next: there is no
concept of the "next-hop". In my case I was using point-to-point
interfaces, so it had no choice.

James.