Comment 76 for bug 520386

Angelo, I was able to connect my guests to the physical newtwork whithout netcf.

I've added the follwing to host's /etc/network/interfaces

auto br0
iface br0 inet static
        address 192.168.2.2
        netmask 255.255.255.0
        bridge_ports eth0
        bridge_stp off
        bridge_fd 0
        bridge_maxwait 0

eth0 interface does not have a separate /etc/network/interfaces entry, br0 is the interface the host is using to connect to the physical network. The bridged interface has a static address in my case but I think that DHCP would work also.

After a reboot, I can use the bridged interface in virt-manager. When configuring the Virtual Network Interface for a guest, I can choose 'Host device eth0 (Bridge br0)' as the source device. With this setting, guest can access the physical network, acquire an IP address from the DHCP server and contact physical machines in my network and also other guests.

It would be nice to be able to configure the bridges in the host machine from virsh / virt-manager but it's not strictly required to get it working :)