On Wed, Oct 2, 2013 at 3:40 PM, Ross Boylan <rossboy...@stanfordalumni.org>
wrote:
>
> Arun made a suggestion that
>> Your 'physical' device eth0/eth2 or whatever needs to be added to the
bridge.
> I believe that is done by the /etc/kvm/kvm-ifup script that is executed
when I
> launch the virtual machine.
> It says, in part
>
> switch=$(ip route ls | \
> awk '/^default / {
> for(i=0;i<NF;i++) { if ($i == "dev") { print $(i+1); next; } }
> }'
> )
> # i.e, switch=eth2 (RB)
>
> # only add the interface to default-route bridge if we
> # have such interface (with default route) and if that
> # interface is actually a bridge.
> # It is possible to have several default routes too
> for br in $switch; do
> if [ -d /sys/class/net/$br/bridge/. ]; then
> brctl addif $br "$1"
> exit # exit with status of brctl
> fi
> done
>
> # I think $1=tap0 as invoked, though maybe its br0 (RB)
>
> Then again, I don't understand things well enough to know what adding
> something to a bridge means, or how that is accomplished.
"/etc/kvm/kvm-ifup" brings up tap0 ($1) and adds it to br0 ($switch/$br).
Since you're already doing the above via "/etc/network/interfaces", you
should choose either to bring up your VM with "-net
tap,script=no,downscript=no,..." or delete the pre-up and post-down lines
from the br0 stanza in "/etc/network/interfaces":
auto br0
iface br0 inet dhcp
bridge_ports all tap0
bridge_stp off
bridge_maxwait 0
bridge_fd 0
