�� 2011��03��24�� 19:16, ������ ����: > When a vm move from one VLAN(e.g. VLAN 1) to another VLAN (e.g. VLAN 2), > it is needed to restart the network connection of guest OS, so that it > can begin a dhcp discover and get a new ip again. But i can't find the > way to restart the guest os's network connection by libvirt (neither > python API nor virsh command). Is any other ways? Hi, Won't virt-manager (if has) in your guest try to restart the network? > PS: i found that the VirtualBox can detach the cable of VMs and > re-attach so that the guest OS will recognize and restart a dhcp > discover when the cable re-attach. I guess the KVM will have some > feature like that , is anybody know something about that? Libvirt supports similar function. # virsh detach-interface # virsh attach-interface Or # virsh detach-device # virsh attach-device the difference between "*-device" and "*-interface" is the accepted arguments, the later one accepts interface xml.