[Bridge] Giving enslaved interface an IP?

Stephen Hemminger shemminger at linux-foundation.org
Mon Oct 18 20:33:58 PDT 2010

On Mon, 18 Oct 2010 19:16:18 -0700
Thomas Taranowski <tom at baringforge.com> wrote:

> I have bridged eth0 and eth1, where eth0 is the world, and eth1 has
> some locally administered targets with normal IPs.  On eth1, I also
> have some other devices with 192.168.x.x addresses I locally assigned.
>  I'd like to give my eth1 a 192.168.x.x address, and treat the
> 192.168.x.x network as something like a local network, where anything
> else get's bridged across to eth0.  I'm running into some problems.
> First, when I try to ping anything on the 192.168.x.x network, it
> get's sent out the wrong interface ( eth0 ), rather than eth1.  I
> expected the bridge to broadcast the arp request to both interfaces.
> Second, giving eth1 an ip address, in addition to being bridged, had
> no obvious effect.  Can I even do this?
> Any suggestions on where to look for additional information on this,
> or things to try?

Don't put IP address on only one interface unless you are
setting up a brouter[1]. If you want to do firewalling then
add ebtables rules to block traffic; doing firewalling
with addressing won't work because the address won't be accessible 
as you found out.

1. A brouter requires additional ebtables to make packets flow.

More information about the Bridge mailing list