Comment 0 for bug 1153842

To reproduce the issue it's enough to attach two volumes to a VM without providing an explicit mount point.

cinder create 1
cinder create 1

nova boot ... vm1

nova volume-attach vmid <volumeid1> auto
nova volume-attach vmid <volumeid2> auto

As a result:

1) When the machine is deleted only one of the volumes returns available on Cinder, the second one figures as still attached.
2) Live migration fails as only one volume is reported in the "block_device_info" dict.

More inconsistent behaviours can happen, for example during cold migration / resize.

Workaround:

Always provide a mount point e.g.:

nova volume-attach vmid <volumeid1> /dev/sdb
nova volume-attach vmid <volumeid2> /dev/sdc