To remove an orphaned volume form an openstack deployment

mysql>delete from volume_admin_metadata where volume_id='9eb308c2-8f2f-4361-b9a2-fd320e11f8ac';
mysql>delete from volumes where id='17035b2d-0496-48b8-bce0-b2418b13b0a2';
# or a snapshot
mysql>delete from snapshot where id='17035b2d-0496-48b8-bce0-b2418b13b0a2';

<3>How to remove and old / unused volume group

select * from services;

select * from services;
+---------------------+---------------------+------------+---------+----+-----------------+------------------+------------------+--------------+----------+-------------------+-----------------+
| created_at          | updated_at          | deleted_at | deleted | id | host            | binary           | topic            | report_count | disabled | availability_zone | disabled_reason |
+---------------------+---------------------+------------+---------+----+-----------------+------------------+------------------+--------------+----------+-------------------+-----------------+
| 2015-11-18 20:06:36 | 2015-11-19 20:45:19 | NULL       |       0 |  1 | os1         | cinder-scheduler | cinder-scheduler |         8807 |        0 | nova              | NULL            |
| 2015-11-18 21:58:11 | 2015-11-19 19:53:53 | NULL       |       0 |  2 | os2         | cinder-volume    | cinder-volume    |         6762 |        0 | nova              | NULL            |
| 2015-11-19 17:26:53 | 2015-11-19 19:55:29 | NULL       |       0 |  3 | os1         | cinder-volume    | cinder-volume    |          878 |        0 | nova              | NULL            |
| 2015-11-19 20:00:36 | 2015-11-19 20:04:46 | NULL       |       0 |  4 | os1@zfssa   | cinder-volume    | cinder-volume    |           25 |        0 | nova              | NULL            |
| 2015-11-19 20:06:27 | 2015-11-19 20:45:11 | NULL       |       0 |  5 | os1@zfssa-2 | cinder-volume    | cinder-volume    |          183 |        0 | nova              | NULL            |
+---------------------+---------------------+------------+---------+----+-----------------+------------------+------------------+--------------+----------+-------------------+-----------------+

Delete old unused volume group

mysql> delete from services where id='4';
Query OK, 1 row affected (0.00 sec)