[CentOS] Multiple IP Addresses for a bridge

Tue May 3 09:40:31 UTC 2011
Arun Khan <knura9 at gmail.com>

On Fri, Apr 29, 2011 at 4:21 PM, Emmanuel Noobadmin
<centos.admin at gmail.com> wrote:
> On 4/29/11, Lucian <lucian at lastdot.org> wrote:
>> Something seems out of order with the above; may I ask what exactly
>> you are trying to achieve?
>> Unless I read it all wrong you want (i.e.) x.x.x.2 on br0 and also on
>> eth0? This cannot work.
> Well, I have a physical connected to the ISP modem/router which
> assigned the connection a block of 8 IPs
> So I already have eth0 bridged to br0 using the IP x.x.x.2
> Now I'm trying to figure out why a virtual guest with an eth0 device
> assigned wth IP x.x.x.3 can't connect anywhere.

The interface from the host OS to the guest also needs to be part of
the bridge.  For instance, in Linux KVM, the "tap" interface presented
by the host OS has to be part of the bridge.   The guest OS can assign
the IP you want and traffic passes bidirectionally.   Don't know about
other Virtualization platforms.

Can you share the output from "/sbin/brctl show"?

This is what my setup looks like (from a Debian setup)

$ /usr/sbin/brctl show
bridge name     bridge id               STP enabled     interfaces
br0             8000.00262d5588d1       no                   eth0
br1             8000.aa9267231e88       no                   tap2

-- Arun Khan