rbd-nbd - map rbd images to nbd device

rbd-nbd is part of Ceph, a massively scalable, open-source, distributed storage system. Please  refer  to
       the Ceph documentation at https://docs.ceph.com/ for more information.

       2010-2014,  Inktank  Storage,  Inc.  and  contributors. Licensed under Creative Commons Attribution Share
       Alike 3.0 (CC-BY-SA-3.0)

dev                                               May 22, 2025                                        RBD-NBD(8)

rbd-nbd  is a client for RADOS block device (rbd) images like rbd kernel module.  It will map a rbd image
       to a nbd (Network Block Device) device, allowing access it as regular local block device.

image-spec is [pool-name]/image-namesnap-spec  is [pool-name]/image-name@snap-name

       The  default  for  pool-name  is  "rbd".  If an image name contains a slash character ('/'), pool-name is
       required.

       rbd-nbd - map rbd images to nbd device

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

       --read-only
              Map read-only.

       --nbds_max*limit*
              Override the parameter nbds_max of NBD kernel module when modprobe, used to limit the count of nbd
              device.

       --max_part*limit*
              Override for module param max_part.

       --exclusive
              Forbid writes by other clients.

       --notrim
              Turn off trim/discard.

       --encryption-format
              Image encryption format.  Possible values: luks, luks1, luks2--encryption-passphrase-file
              Path of file containing a passphrase for unlocking image encryption.

       --io-timeout*seconds*
              Override device timeout. Linux kernel will default to a 30 second request timeout.  Allow the user
              to optionally specify an alternate timeout.

       --reattach-timeout*seconds*
              Specify timeout for the kernel to wait for a new rbd-nbd process is attached after the old process
              is detached. The default is 30 second.

       --snap-id*snapid*
              Specify a snapshot to map/unmap/attach/detach by ID instead of by name.

rbd(8)

rbd-nbd [-c conf] [--read-only] [--device nbddevice] [--snap-id snap-id] [--nbds_max limit] [--max_part limit] [--exclusive] [--notrim] [--encryption-format format] [--encryption-passphrase-file passphrase-file] [--io-timeout seconds] [--reattach-timeout seconds] map image-spec | snap-specrbd-nbd unmap nbddevice | image-spec | snap-specrbd-nbd list-mapped
       rbd-nbd attach --device nbddeviceimage-spec | snap-specrbd-nbd detach nbddevice | image-spec | snap-spec