Description of NFS storage configuration options

Configuration option = Default value	Description
[DEFAULT]
nfs_mount_attempts = 3	(IntOpt) The number of attempts to mount nfs shares before raising an error. At least one attempt will be made to mount an nfs share, regardless of the value specified.
nfs_mount_options = None	(StrOpt) Mount options passed to the nfs client. See section of the nfs man page for details.
nfs_mount_point_base = $state_path/mnt	(StrOpt) Base dir containing mount points for nfs shares.
nfs_oversub_ratio = 1.0	(FloatOpt) This will compare the allocated to available space on the volume destination. If the ratio exceeds this number, the destination will no longer be valid.
nfs_shares_config = /etc/cinder/nfs_shares	(StrOpt) File with the list of available nfs shares
nfs_sparsed_volumes = True	(BoolOpt) Create volumes as sparsed files which take no space.If set to False volume is created as regular file.In such case volume creation takes a lot of time.
nfs_used_ratio = 0.95	(FloatOpt) Percent of ACTUAL usage of the underlying volume before no new volumes can be allocated to the volume destination.