Description of RBD configuration options

Configuration option = Default value	Description
[DEFAULT]
rbd_store_ceph_conf = /etc/ceph/ceph.conf	(StrOpt) Ceph configuration file path. If <None>, librados will locate the default config. If using cephx authentication, this file should include a reference to the right keyring in a client.<USER> section.
rbd_store_chunk_size = 8	(IntOpt) RADOS images will be chunked into objects of this size (in megabytes). For best performance, this should be a power of two.
rbd_store_pool = images	(StrOpt) RADOS pool in which images are stored.
rbd_store_user = None	(StrOpt) RADOS user to authenticate as (only applicable if using Cephx. If <None>, a default will be chosen based on the client. section in rbd_store_ceph_conf).