Option "rpc_backend" from group "DEFAULT" is deprecated for removal. Its value may be silently ignored in the future.
WARNING: cell0 mapping not found - not syncing cell0.
/usr/lib/python2.7/site-packages/pymysql/cursors.py:146: Warning: Duplicate index 'block_device_mapping_instance_uuid_virtual_name_device_name_idx' defined on the table 'nova.block_device_mapping'. This is deprecated and will be disallowed in a future release.
result = self._query(query)
Populate the Compute databases:
# su -s /bin/sh -c "nova-manage api_db sync" nova# su -s /bin/sh -c "nova-manage db sync" nova 这一步时出现以上问题