Subject: Re: Two interfaces on same network
To: Manuel Bouyer <bouyer@antioche.eu.org>
From: Arto Huusko <arto.huusko@utu.fi>
List: netbsd-help
Date: 09/21/2001 00:40:08
On Thu, 20 Sep 2001, Manuel Bouyer wrote:

> You machine has wong time. this caused me to miss your message because
> it was not at the bottom of my mailbox.

Uh, yes, a slight mistake; the machine didn't get its time from network
and I didn't notice a thing. I missed my mail too, so I sent it twice :(

> > This works quite nicely, meaning that the bridge does work. However,
> > the bridge box itself is useless now for anything else than bridging:
> > I can use either of the interfaces to access the network behind that
> > interface, but not both.
> >
> > The configuration is like this (I'm building this at home, but it'll
> > go to real use later):
> >
> > ne0: inet 10.0.0.5 netmask 255.255.255.0
> > ep0: inet 10.0.0.4 netmask 255.255.255.0
> >
> > ne0 is connected to the internal LAN, ep0 is the way out.
>
> You don't have to give an IP to each interface.
> What happens if you give only an IP to one interface and just configure
> the second 'up' ?

Um, I seem to remember that the situation didn't change much.
The interface that was 'up', if it was configured first, could be used
as normal. I did not try did bridging work at that time.

Thank you for your reply, but this is a dead issue now. I realised that
the box should've done too many things that bridging really was not an
option. Because the machine really needed IPs on both interfaces. Happily,
NAT was an alternative (I tried bridging because I first had understood
NAT was not possible) and everything works now great.


But still, bridging aside, I am curious: can two interfaces on a computer
be in the same network? I pretty much came to the conclusion that no
but I still have a nagging feeling I'm wrong. How would the system
be configured in that case to work properly?

-- Arto Huusko