Provided by: ceph-common_0.41-1ubuntu2_amd64 bug


       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 startup.

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

       -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.

       --user username
              Specifies the username to use with the map command.

       --secret filename
              Specifies a file containing the secret to use with the map command.


       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 --size.

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

       rm [image-name]
              Deletes an rbd image (including all data blocks). If the image has snapshots,  this
              fails and nothing is deleted.

       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-image.

       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 specified.

       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.

       snap purge [image-name]
              Removes all snapshots from an image.

       map [image-name]
              Maps the specified image to a block device via the rbd kernel module.

       unmap [device-path]
              Unmaps the block device that was mapped via the rbd kernel module.

              Show the rbd images that are mapped via the rbd kernel module.


       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


       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

       To map an image via the kernel with cephx enabled:

       rbd map myimage --user admin --secret secretfile

       To unmap an image:

       rbd unmap /dev/rbd0


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


       ceph(8), rados(8)


       2011, New Dream Network