remember the bridge entirely replaces your NICs in /etc/network/interfaces, so:
Code:
auto lo
iface lo inet loopback
auto bridge01
iface bridge01 inet dhcp
pre-up ifconfig eth0 down
pre-up ifconfig eth1 down
pre-up brctl addbr bridge01
pre-up brctl addif bridge01 eth0
pre-up brctl addif bridge01 eth1
pre-up ifconfig eth0 0.0.0.0
pre-up ifconfig eth1 0.0.0.0
post-down ifconfig eth0 down
post-down ifconfig eth1 down
post-down ifconfig bridge01 down
post-down brctl delif bridge01 eth0
post-down brctl delif bridge01 eth1
post-down brctl delbr bridge01
You can then apt-get install ntop or darkstat and point it at the bridge01 instead of eth0 or eth1 to watch traffic.
Oh yeah, sometimes it seems 'sudo /etc/init.d/networking restart' didn't actually clear the old file (in Ubuntu 9.04 I checked ifconfig and saw the old eth0 settings still) so I just rebooted and it works fine.