Is hot-plugging and hot-unplugging of network interfaces supported in RHEL5 KVM?

Issue

• Is hot-plugging and hot-unplugging of network interfaces supported in RHEL5 KVM?

• Why hotplugging a virtio network card to a kvm guest running under RHEL5 fails with the below error message?

  # virsh attach-interface <guest name> bridge br0 --mac 02:17:42:2F:99:01
  error: Failed to attach interface
  error: this function is not supported by the connection driver: installed qemu version does not support host_net_add
  

• Why hot-unplugging a virtio network interface in RHEL5 KVM guest fails with the below error message?

  # virsh detach-interface <guest name> bridge --mac '54:52:00:27:E7:C7'
  error: Failed to detach interface
  error: operation failed: unable to determine original VLAN