# Refs

http://www.linuxfoundation.org/collaborate/workgroups/networking/bridge
http://openvpn.net/index.php/open-source/documentation/miscellaneous/76-ethernet-bridging.html
http://www.linux-france.org/prj/inetdoc/articles/vm/vm.network.tun-tap.html
http://wiki.debian.org/VirtualNetworking


# Run KVM/Qemu using a bridge

kvm -hda test.img -cdrom Debian-Lenny.iso -boot d -vnc :0 -k fr -net nic -net tap,ifname=v_john0,script=no,downscript=no
kvm -hda test.img -cdrom Debian-Lenny.iso -boot d -vnc :0 -k fr -net nic -net tap,ifname=v_john0,script=no,downscript=no -monitor stdio
kvm -hda test.img -cdrom Debian-Lenny.iso -boot d -vnc :0 -k fr -net nic -net tap,ifname=v_john0,script=no,downscript=no --daemonize
screen kvm -hda test.img -cdrom Debian-Lenny.iso -boot d -vnc :0 -k fr -net nic -net tap,ifname=v_john0,script=no,downscript=no -monitor stdio


# Notes

chown root:uml /dev/net/tun
chmod 660 /dev/net/tun

brctl addbr uml-bridge
brctl setfd uml-bridge 0
brctl sethello uml-bridge 0
brctl stp uml-bridge off

ifconfig eth0 0.0.0.0 promisc up
ifconfig uml-bridge 192.168.0.100 netmask 255.255.255.0 up
brctl addif uml-bridge eth0

tunctl -u umluser -t uml-conn0
ifconfig uml-conn0 0.0.0.0 promisc up
brctl addif uml-bridge uml-conn0


##############################################################################
#!/bin/bash

#################################
# Set up Ethernet bridge on Linux
# Requires: bridge-utils
#################################

# Define Bridge Interface
br="br0"

# Define list of TAP interfaces to be bridged,
# for example tap="tap0 tap1 tap2".
tap="tap0"

# Define physical ethernet interface to be bridged
# with TAP interface(s) above.
eth="eth0"
eth_ip="192.168.8.4"
eth_netmask="255.255.255.0"
eth_broadcast="192.168.8.255"

for t in $tap; do
    openvpn --mktun --dev $t
done

brctl addbr $br
brctl addif $br $eth

for t in $tap; do
    brctl addif $br $t
done

for t in $tap; do
    ifconfig $t 0.0.0.0 promisc up
done

ifconfig $eth 0.0.0.0 promisc up

ifconfig $br $eth_ip netmask $eth_netmask broadcast $eth_broadcast