https://blog.scottlowe.org/2012/11/07/using-vlans-with-ovs-and-libvirt/
http://docs.openvswitch.org/en/latest/howto/libvirt/
https://libvirt.org/formatnetwork.html
https://stackoverflow.com/questions/30622680/kvm-ovs-bridged-network-how-to-configure