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       rbd - manage rados block device (RBD) images


       rbd  [ -c ceph.conf ] [ -m monaddr ] [ -p | --pool pool ] [ --size size
       ] [ --order bits ] [ command ... ]


       rbd is a utility for manipulating rados block device (RBD) images, used
       by  the  Linux rbd driver and the rbd storage driver for Qemu/KVM.  RBD
       images are simple block devices  that  are  striped  over  objects  and
       stored  in  a RADOS object store.  The size of the objects the image is
       striped over must be a power of two.


       -c ceph.conf, --conf ceph.conf
              Use  ceph.conf  configuration  file  instead  of   the   default
              /etc/ceph/ceph.conf   to   determine  monitor  addresses  during

       -m monaddress[:port]
              Connect  to  specified  monitor  (instead  of  looking   through

       -p pool, --pool pool
              Interact with the given pool.  Required by most commands.


       --size size-in-mb
              Specifies the size (in megabytes) of the new rbd image.

       --order bits
              Specifies  the  object  size expressed as a number of bits, such
              that the object size is 1 << order. The default is 22 (4 MB).

       --snap snap
              Specifies the snapshot name for the specific operation.


       ls [ pool-name ]
              Will list all rbd images listed in the rbd_directory object.

       info [ image-name ]
              Will dump information (such as size and order) about a  specific
              rbd image.

       create [ image-name ]
              Will create a new rbd image.  You must also specify the size via

       resize [ image-name ]
              Resizes  rbd  image.   The  size  parameter  also  needs  to  be

       rm [ image-name ]
              Deletes rbd image (including all data blocks)

       rm [ image-name ]
              Deletes rbd image (including all data blocks)

       export [ image-name ] [ dest-path ]
              Exports image to dest path.

       import [ path ] [ dest-image ]
              Creates a new image and imports its data from path.

       cp [ src-image ] [ dest-image ]
              Copies  the  content of a src-image into the newly created dest-

       mv [ src-image ] [ dest-image ]
              Renames an image.

       snap ls [ image-name ]
              Dumps the list of snapshots inside a specific image.

       snap create [ image-name ]
              Creates a new snapshot. Requires  the  snapshot  name  parameter

       snap rollback [ image-name ]
              Rollback  image  content  to snapshot. This will iterate through
              the entire blocks array and update the data head content to  the
              snapshotted version.

       snap rm [ image-name ]
              Removes the specified snapshot.


       In  addition to using the --pool and the --snap options, the image name
       can include both the pool name and the snapshot name.  The  image  name
       format is as follows:


       Thus  an  image  name  that  contains  a slash character ('/') requires
       specifying the pool name explicitly.


       To create a new rbd image that is 100 GB:

              rbd -p mypool create myimage --size 102400

       or alternatively

              rbd create mypool/myimage --size 102400

       To use a non-default object size (8 MB):

              rbd create mypool/myimage --size 102400 --order 23

       To delete an rbd image (be careful!):

              rbd rm mypool/myimage

              To create a new snapshot:

              rbd create mypool/myimage@mysnap


       rbd is part of the Ceph distributed file system.  Please refer  to  the
       Ceph wiki at for more information.