现象：挂载了Cinder Volume的实例无法动态迁移
[root@node-5 nova]# tail -f compute.log
2016-01-13 16:36:12.870 18762 ERROR nova.virt.libvirt.driver [-] [instance: 9d3e4665-801e-44bd-b93a-82951102cc22] Live Migration failure: unable to resolve '/var/lib/nova/mnt/e6271a95925950a6ebb1c8a11cf3c4c3/volume-2bcf54d7-6797-4e88-8202-1054425980d1': No such file or directory
[root@node-5 nova]# mount
168.5.22.100:/volumes on /var/lib/nova/mnt/e6271a95925950a6ebb1c8a11cf3c4c3 type nfs (rw,addr=168.5.22.100)
[root@node-4 nova]# mount
没有“168.5.22.100:/volumes on ...”
手动挂载：
[root@node-4 nova]# mount 168.5.22.100:/volumes /var/lib/nova/mnt/e6271a95925950a6ebb1c8a11cf3c4c3
再迁移就成功：
nova live-migration 9d3e4665-801e-44bd-b93a-82951102cc22 node-4.evecom.net