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I configured openstack with ceph following this doc using ubuntu 14.04:
http://docs.ceph.com/docs/master/rbd/rbd-openstack/

However, there will be errors when uploading a image: =====================================================
2015-05-06 12:01:10.622 121294 TRACE glance.api.v1.upload_utils Traceback (most recent call last):
2015-05-06 12:01:10.622 121294 TRACE glance.api.v1.upload_utils File "/usr/lib/python2.7/dist-packages/glance/api/v1/upload_utils.py", line 107, in upload_data_to_store
2015-05-06 12:01:10.622 121294 TRACE glance.api.v1.upload_utils context=req.context)
2015-05-06 12:01:10.622 121294 TRACE glance.api.v1.upload_utils File "/usr/lib/python2.7/dist-packages/glance_store/backend.py", line 342, in store_add_to_backend
2015-05-06 12:01:10.622 121294 TRACE glance.api.v1.upload_utils (location, size, checksum, metadata) = store.add(image_id, data, size)
2015-05-06 12:01:10.622 121294 TRACE glance.api.v1.upload_utils File "/usr/lib/python2.7/dist-packages/glance_store/_drivers/rbd.py", line 326, in add
2015-05-06 12:01:10.622 121294 TRACE glance.api.v1.upload_utils with rados.Rados(conffile=self.conf_file, rados_id=self.user) as conn:
2015-05-06 12:01:10.622 121294 TRACE glance.api.v1.upload_utils AttributeError: 'NoneType' object has no attribute 'Rados' =================================================================

the error is because python-rados is not installed.
the doc only mentioned "apt install python-rbd" for glance-api node, so I guess the dependency of python-rados is missing?
If there should be no dependency, the above doc should mention to install python-rados too.