--may-exist add-br xenbr3
--may-exist add-port xenbr3 eth3
br-set-external-id xenbr3 xs-network-uuids 2902ae1b-8013-897a-b697-0b200ea3aaa5;db7bdc03-074d-42ae-fc73-9b06de1d57f6
--may-exist add-br xenbr3
--may-exist add-port xenbr3 eth3
br-set-external-id xenbr3 xs-network-uuids 2902ae1b-8013-897a-b697-0b200ea3aaa5;db7bdc03-074d-42ae-fc73-9b06de1d57f6