[libvirt] configuring a disconnected <interface>

Hi List, Like most of us, I've bought my actual computer with an Ethernet interface card, that I can connect to a wall jack at will. It's quite easy to disconnect the Ethernet cable from the wall, as well. I would like to expose this behavior to virtual computers, too. Via libvirt, of course. That's useful, since an admin may need to disconnect a running VM from a network temporarily, without resorting to hot-unplugging its nic. How should the domxml represent this situation? An interface that is connected to a specific LAN1 bridge is <interface type='bridge'> <source bridge='LAN1'> <target dev='vnet1'/> <model type='virtio'/> </interface> Would the following make sense for an interface with no bridge at the source? <interface type='bridge'> <source/> <target dev='vnet1'/> <model type='virtio'/> </interface> And how about the recommended config for <interface>s, which is type='network'? Would it make sense to predefine <network> <name>null-bridge-network</name> <forward mode='bridge'> <bridge/> </network> so that <interface type='network'> <source network='null-bridge-network'/> </interface> means "keep this interface dangling out there"? Regards, Dan.