# The loopback network interface
auto lo
iface lo inet loopback

# The primary network interface
auto br0
iface br0 inet dhcp
  bridge_ports eth0
  bridge_fd 9      ## from the libvirt docs (forward delay time)
  bridge_hello 2   ## from the libvirt docs (hello time)
  bridge_maxage 12 ## from the libvirt docs (maximum message age)
  bridge_stp off   ## from the libvirt docs (spanning tree protocol)

iface eth0 inet manual
  up ifconfig $IFACE 0.0.0.0 up
  up ip link set $IFACE promisc on
  down ip link set $IFACE promisc off
  down ifconfig $IFACE down