It fails to unrescue when the vmware VM is in powered-on state and also it seems to be leaking when the vm is in ERROR state.

# nova boot --image cirros-0.3.1-x86_64-disk.vmdk --flavor m1.tiny foo
# nova list
+--------------------------------------+------+--------+------------+-------------+--------------------------+
| ID                                   | Name | Status | Task State | Power State | Networks                 |
+--------------------------------------+------+--------+------------+-------------+--------------------------+
| c1ed3110-a054-420c-bc70-0bdb254fcc8c | foo  | ACTIVE | -          | Running     | novanetwork=192.168.32.5 |
+--------------------------------------+------+--------+------------+-------------+--------------------------+
# nova rescue foo
[root@jhenner-node-permanent-7v0 ~(keystone_admin)]# nova list
+--------------------------------------+------+--------+------------+-------------+--------------------------+
| ID                                   | Name | Status | Task State | Power State | Networks                 |
+--------------------------------------+------+--------+------------+-------------+--------------------------+
| c1ed3110-a054-420c-bc70-0bdb254fcc8c | foo  | ACTIVE | rescuing   | Running     | novanetwork=192.168.32.5 |
+--------------------------------------+------+--------+------------+-------------+--------------------------+

******* Wait until the -rescue VM gets powered on, then the nova seems to switch the state:

[root@jhenner-node-permanent-7v0 ~(keystone_admin)]# nova list
+--------------------------------------+------+--------+------------+-------------+--------------------------+
| ID                                   | Name | Status | Task State | Power State | Networks                 |
+--------------------------------------+------+--------+------------+-------------+--------------------------+
| c1ed3110-a054-420c-bc70-0bdb254fcc8c | foo  | RESCUE | -          | Shutdown    | novanetwork=192.168.32.5 |
+--------------------------------------+------+--------+------------+-------------+--------------------------+
# nova unrescue foo
# nova list
+--------------------------------------+------+--------+------------+-------------+--------------------------+
| ID                                   | Name | Status | Task State | Power State | Networks                 |
+--------------------------------------+------+--------+------------+-------------+--------------------------+
| c1ed3110-a054-420c-bc70-0bdb254fcc8c | foo  | RESCUE | unrescuing | Shutdown    | novanetwork=192.168.32.5 |
+--------------------------------------+------+--------+------------+-------------+--------------------------+
[root@jhenner-node-permanent-7v0 ~(keystone_admin)]# nova list
+--------------------------------------+------+--------+------------+-------------+--------------------------+
| ID                                   | Name | Status | Task State | Power State | Networks                 |
+--------------------------------------+------+--------+------------+-------------+--------------------------+
| c1ed3110-a054-420c-bc70-0bdb254fcc8c | foo  | ERROR  | -          | Shutdown    | novanetwork=192.168.32.5 |
+--------------------------------------+------+--------+------------+-------------+--------------------------+


# nova delete foo

******* this leaves the -rescue VM in the vcenter.

# rpm -q openstack-nova-compute
openstack-nova-compute-2014.1-7.el7ost.noarch