conn = LibvirtConnection.getConnectionByVmName(vmName);
vm = getDomain(conn, vmName);
List<InterfaceDef> pluggedNics = getInterfaces(conn, vmName);
for (InterfaceDef pluggedNic : pluggedNics) {
if (pluggedNic.getMacAddress().equalsIgnoreCase(nic.getMac())) {
vm.detachDevice(pluggedNic.toString());
// We don't know which "traffic type" is associated with
// each interface at this point, so inform all vif drivers
for(VifDriver vifDriver : getAllVifDrivers()){
vifDriver.unplug(pluggedNic);
}