我写了一个煤渣驱动程序，但它无法启动。它给了我以下错误
2016-11-29 17:01:56.807 INFO cinder.volume.manager [req-4fe59a59-bb73-48e4-bfca-e8730e9a74c8 None None] Determined volume DB was empty at startup.
2016-11-29 17:01:56.808 DEBUG cinder.volume.manager [req-4fe59a59-bb73-48e4-bfca-e8730e9a74c8 None None] Cinder Volume DB check: vol_db_empty=True from (pid=25266) __init__ /opt/stack/cinder/cinder/volume/manager.py:193
2016-11-29 17:01:56.837 WARNING cinder.keymgr.conf_key_mgr [req-4fe59a59-bb73-48e4-bfca-e8730e9a74c8 None None] This key manager is insecure and is not recommended for production deployments
2016-11-29 17:01:56.916 ERROR cinder.cmd.volume [req-4fe59a59-bb73-48e4-bfca-e8730e9a74c8 None None] Volume service akdevstck@ixsystems-iscsi failed to start.
2016-11-29 17:01:56.916 TRACE cinder.cmd.volume Traceback (most recent call last):
2016-11-29 17:01:56.916 TRACE cinder.cmd.volume File "/opt/stack/cinder/cinder/cmd/volume.py", line 100, in main
2016-11-29 17:01:56.916 TRACE cinder.cmd.volume cluster=cluster)
2016-11-29 17:01:56.916 TRACE cinder.cmd.volume File "/opt/stack/cinder/cinder/service.py", line 387, in create
2016-11-29 17:01:56.916 TRACE cinder.cmd.volume cluster=cluster)
2016-11-29 17:01:56.916 TRACE cinder.cmd.volume File "/opt/stack/cinder/cinder/service.py", line 206, in __init__
2016-11-29 17:01:56.916 TRACE cinder.cmd.volume *args, **kwargs)
2016-11-29 17:01:56.916 TRACE cinder.cmd.volume File "/opt/stack/cinder/cinder/volume/manager.py", line 226, in __init__
2016-11-29 17:01:56.916 TRACE cinder.cmd.volume active_backend_id=curr_active_backend_id)
2016-11-29 17:01:56.916 TRACE cinder.cmd.volume File "/usr/local/lib/python2.7/dist-packages/oslo_utils/importutils.py", line 44, in import_object
2016-11-29 17:01:56.916 TRACE cinder.cmd.volume return import_class(import_str)(*args, **kwargs)
2016-11-29 17:01:56.916 TRACE cinder.cmd.volume File "/opt/stack/cinder/cinder/volume/drivers/ixsystems/iscsi.py", line 57, in __init__
2016-11-29 17:01:56.916 TRACE cinder.cmd.volume self.configuration.ixsystems_iqn_prefix += ':'
2016-11-29 17:01:56.916 TRACE cinder.cmd.volume File "/opt/stack/cinder/cinder/volume/configuration.py", line 80, in __getattr__
2016-11-29 17:01:56.916 TRACE cinder.cmd.volume return getattr(local_conf, value)
2016-11-29 17:01:56.916 TRACE cinder.cmd.volume File "/usr/local/lib/python2.7/dist-packages/oslo_config/cfg.py", line 3120, in __getattr__
2016-11-29 17:01:56.916 TRACE cinder.cmd.volume return self._conf._get(name, self._group)
2016-11-29 17:01:56.916 TRACE cinder.cmd.volume File "/usr/local/lib/python2.7/dist-packages/oslo_config/cfg.py", line 2731, in _get
2016-11-29 17:01:56.916 TRACE cinder.cmd.volume value = self._do_get(name, group, namespace)
2016-11-29 17:01:56.916 TRACE cinder.cmd.volume File "/usr/local/lib/python2.7/dist-packages/oslo_config/cfg.py", line 2761, in _do_get
2016-11-29 17:01:56.916 TRACE cinder.cmd.volume if opt.mutable and namespace is None:
2016-11-29 17:01:56.916 TRACE cinder.cmd.volume AttributeError: 'StrOpt' object has no attribute 'mutable'
2016-11-29 17:01:56.916 TRACE cinder.cmd.volume
2016-11-29 17:01:57.190 ERROR cinder.cmd.volume [req-4fe59a59-bb73-48e4-bfca-e8730e9a74c8 None None] No volume service(s) started successfully, terminating.
c-vol failed to start
stack@akdevstck:~/devstack$
请帮助解决问题。