Comment 3 for bug 1447288

Turns out that with create from snapshot and others, none of the additional parameters are actually set in the horizon call. If for example you run "create from snapshot" using horizon and check the body of the request as it enters Cinders API (v2/volumes.py) you'll notice there are no parameters provided:

{u'volume': {u'status': u'creating', u'user_id': None, u'description': u'', u'imageRef': None, u'availability_zone': None, 'scheduler_hints': {}, u'attach_status': u'detached', u'source_volid': None, u'name': u'fromsnap1', u'metadata': {}, u'consistencygroup_id': None, u'volume_type': u'lvmdriver-1', u'snapshot_id': None, u'project_id': None, u'source_replica': None, u'size': 1}}