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diff --git a/doc/man/8/rbd.rst b/doc/man/8/rbd.rst new file mode 100644 index 00000000..14a6ad64 --- /dev/null +++ b/doc/man/8/rbd.rst @@ -0,0 +1,919 @@ +:orphan: + +=============================================== + rbd -- manage rados block device (RBD) images +=============================================== + +.. program:: rbd + +Synopsis +======== + +| **rbd** [ -c *ceph.conf* ] [ -m *monaddr* ] [--cluster *cluster-name*] + [ -p | --pool *pool* ] [ *command* ... ] + + +Description +=========== + +**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. + + +Options +======= + +.. option:: -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. + +.. option:: -m monaddress[:port] + + Connect to specified monitor (instead of looking through ceph.conf). + +.. option:: --cluster cluster-name + + Use different cluster name as compared to default cluster name *ceph*. + +.. option:: -p pool-name, --pool pool-name + + Interact with the given pool. Required by most commands. + +.. option:: --namespace namespace-name + + Use a pre-defined image namespace within a pool + +.. option:: --no-progress + + Do not output progress information (goes to standard error by + default for some commands). + + +Parameters +========== + +.. option:: --image-format format-id + + Specifies which object layout to use. The default is 2. + + * format 1 - (deprecated) Use the original format for a new rbd image. This + format is understood by all versions of librbd and the kernel rbd module, + but does not support newer features like cloning. + + * format 2 - Use the second rbd format, which is supported by + librbd and kernel since version 3.11 (except for striping). This adds + support for cloning and is more easily extensible to allow more + features in the future. + +.. option:: -s size-in-M/G/T, --size size-in-M/G/T + + Specifies the size of the new rbd image or the new size of the existing rbd + image in M/G/T. If no suffix is given, unit M is assumed. + +.. option:: --object-size size-in-B/K/M + + Specifies the object size in B/K/M. Object size will be rounded up the + nearest power of two; if no suffix is given, unit B is assumed. The default + object size is 4M, smallest is 4K and maximum is 32M. + +.. option:: --stripe-unit size-in-B/K/M + + Specifies the stripe unit size in B/K/M. If no suffix is given, unit B is + assumed. See striping section (below) for more details. + +.. option:: --stripe-count num + + Specifies the number of objects to stripe over before looping back + to the first object. See striping section (below) for more details. + +.. option:: --snap snap + + Specifies the snapshot name for the specific operation. + +.. option:: --id username + + Specifies the username (without the ``client.`` prefix) to use with the map command. + +.. option:: --keyring filename + + Specifies a keyring file containing a secret for the specified user + to use with the map command. If not specified, the default keyring + locations will be searched. + +.. option:: --keyfile filename + + Specifies a file containing the secret key of ``--id user`` to use with the map command. + This option is overridden by ``--keyring`` if the latter is also specified. + +.. option:: --shared lock-tag + + Option for `lock add` that allows multiple clients to lock the + same image if they use the same tag. The tag is an arbitrary + string. This is useful for situations where an image must + be open from more than one client at once, like during + live migration of a virtual machine, or for use underneath + a clustered filesystem. + +.. option:: --format format + + Specifies output formatting (default: plain, json, xml) + +.. option:: --pretty-format + + Make json or xml formatted output more human-readable. + +.. option:: -o krbd-options, --options krbd-options + + Specifies which options to use when mapping or unmapping an image via the + rbd kernel driver. krbd-options is a comma-separated list of options + (similar to mount(8) mount options). See kernel rbd (krbd) options section + below for more details. + +.. option:: --read-only + + Map the image read-only. Equivalent to -o ro. + +.. option:: --image-feature feature-name + + Specifies which RBD format 2 feature should be enabled when creating + an image. Multiple features can be enabled by repeating this option + multiple times. The following features are supported: + + * layering: layering support + * striping: striping v2 support + * exclusive-lock: exclusive locking support + * object-map: object map support (requires exclusive-lock) + * fast-diff: fast diff calculations (requires object-map) + * deep-flatten: snapshot flatten support + * journaling: journaled IO support (requires exclusive-lock) + * data-pool: erasure coded pool support + +.. option:: --image-shared + + Specifies that the image will be used concurrently by multiple clients. + This will disable features that are dependent upon exclusive ownership + of the image. + +.. option:: --whole-object + + Specifies that the diff should be limited to the extents of a full object + instead of showing intra-object deltas. When the object map feature is + enabled on an image, limiting the diff to the object extents will + dramatically improve performance since the differences can be computed + by examining the in-memory object map instead of querying RADOS for each + object within the image. + +.. option:: --limit + + Specifies the limit for the number of snapshots permitted. + +Commands +======== + +.. TODO rst "option" directive seems to require --foo style options, parsing breaks on subcommands.. the args show up as bold too + +:command:`bench` --io-type <read | write | readwrite | rw> [--io-size *size-in-B/K/M/G/T*] [--io-threads *num-ios-in-flight*] [--io-total *size-in-B/K/M/G/T*] [--io-pattern seq | rand] [--rw-mix-read *read proportion in readwrite*] *image-spec* + Generate a series of IOs to the image and measure the IO throughput and + latency. If no suffix is given, unit B is assumed for both --io-size and + --io-total. Defaults are: --io-size 4096, --io-threads 16, --io-total 1G, + --io-pattern seq, --rw-mix-read 50. + +:command:`children` *snap-spec* + List the clones of the image at the given snapshot. This checks + every pool, and outputs the resulting poolname/imagename. + + This requires image format 2. + +:command:`clone` [--object-size *size-in-B/K/M*] [--stripe-unit *size-in-B/K/M* --stripe-count *num*] [--image-feature *feature-name*] [--image-shared] *parent-snap-spec* *child-image-spec* + Will create a clone (copy-on-write child) of the parent snapshot. + Object size will be identical to that of the parent image unless + specified. Size will be the same as the parent snapshot. The --stripe-unit + and --stripe-count arguments are optional, but must be used together. + + The parent snapshot must be protected (see `rbd snap protect`). + This requires image format 2. + +:command:`config global get` *config-entity* *key* + Get a global-level configuration override. + +:command:`config global list` [--format plain | json | xml] [--pretty-format] *config-entity* + List global-level configuration overrides. + +:command:`config global set` *config-entity* *key* *value* + Set a global-level configuration override. + +:command:`config global remove` *config-entity* *key* + Remove a global-level configuration override. + +:command:`config image get` *image-spec* *key* + Get an image-level configuration override. + +:command:`config image list` [--format plain | json | xml] [--pretty-format] *image-spec* + List image-level configuration overrides. + +:command:`config image set` *image-spec* *key* *value* + Set an image-level configuration override. + +:command:`config image remove` *image-spec* *key* + Remove an image-level configuration override. + +:command:`config pool get` *pool-name* *key* + Get a pool-level configuration override. + +:command:`config pool list` [--format plain | json | xml] [--pretty-format] *pool-name* + List pool-level configuration overrides. + +:command:`config pool set` *pool-name* *key* *value* + Set a pool-level configuration override. + +:command:`config pool remove` *pool-name* *key* + Remove a pool-level configuration override. + +:command:`cp` (*src-image-spec* | *src-snap-spec*) *dest-image-spec* + Copy the content of a src-image into the newly created dest-image. + dest-image will have the same size, object size, and image format as src-image. + +:command:`create` (-s | --size *size-in-M/G/T*) [--image-format *format-id*] [--object-size *size-in-B/K/M*] [--stripe-unit *size-in-B/K/M* --stripe-count *num*] [--thick-provision] [--no-progress] [--image-feature *feature-name*]... [--image-shared] *image-spec* + Will create a new rbd image. You must also specify the size via --size. The + --stripe-unit and --stripe-count arguments are optional, but must be used together. + If the --thick-provision is enabled, it will fully allocate storage for + the image at creation time. It will take a long time to do. + Note: thick provisioning requires zeroing the contents of the entire image. + +:command:`deep cp` (*src-image-spec* | *src-snap-spec*) *dest-image-spec* + Deep copy the content of a src-image into the newly created dest-image. + Dest-image will have the same size, object size, image format, and snapshots as src-image. + +:command:`device list` [-t | --device-type *device-type*] [--format plain | json | xml] --pretty-format + Show the rbd images that are mapped via the rbd kernel module + (default) or other supported device. + +:command:`device map` [-t | --device-type *device-type*] [--read-only] [--exclusive] [-o | --options *device-options*] *image-spec* | *snap-spec* + Map the specified image to a block device via the rbd kernel module + (default) or other supported device (*nbd* on Linux or *ggate* on + FreeBSD). + + The --options argument is a comma separated list of device type + specific options (opt1,opt2=val,...). + +:command:`device unmap` [-t | --device-type *device-type*] [-o | --options *device-options*] *image-spec* | *snap-spec* | *device-path* + Unmap the block device that was mapped via the rbd kernel module + (default) or other supported device. + + The --options argument is a comma separated list of device type + specific options (opt1,opt2=val,...). + +:command:`diff` [--from-snap *snap-name*] [--whole-object] *image-spec* | *snap-spec* + Dump a list of byte extents in the image that have changed since the specified start + snapshot, or since the image was created. Each output line includes the starting offset + (in bytes), the length of the region (in bytes), and either 'zero' or 'data' to indicate + whether the region is known to be zeros or may contain other data. + +:command:`du` [-p | --pool *pool-name*] [*image-spec* | *snap-spec*] + Will calculate the provisioned and actual disk usage of all images and + associated snapshots within the specified pool. It can also be used against + individual images and snapshots. + + If the RBD fast-diff feature is not enabled on images, this operation will + require querying the OSDs for every potential object within the image. + +:command:`export` [--export-format *format (1 or 2)*] (*image-spec* | *snap-spec*) [*dest-path*] + Export image to dest path (use - for stdout). + The --export-format accepts '1' or '2' currently. Format 2 allow us to export not only the content + of image, but also the snapshots and other properties, such as image_order, features. + +:command:`export-diff` [--from-snap *snap-name*] [--whole-object] (*image-spec* | *snap-spec*) *dest-path* + Export an incremental diff for an image to dest path (use - for stdout). If + an initial snapshot is specified, only changes since that snapshot are included; otherwise, + any regions of the image that contain data are included. The end snapshot is specified + using the standard --snap option or @snap syntax (see below). The image diff format includes + metadata about image size changes, and the start and end snapshots. It efficiently represents + discarded or 'zero' regions of the image. + +:command:`feature disable` *image-spec* *feature-name*... + Disable the specified feature on the specified image. Multiple features can + be specified. + +:command:`feature enable` *image-spec* *feature-name*... + Enable the specified feature on the specified image. Multiple features can + be specified. + +:command:`flatten` *image-spec* + If image is a clone, copy all shared blocks from the parent snapshot and + make the child independent of the parent, severing the link between + parent snap and child. The parent snapshot can be unprotected and + deleted if it has no further dependent clones. + + This requires image format 2. + +:command:`group create` *group-spec* + Create a group. + +:command:`group image add` *group-spec* *image-spec* + Add an image to a group. + +:command:`group image list` *group-spec* + List images in a group. + +:command:`group image remove` *group-spec* *image-spec* + Remove an image from a group. + +:command:`group ls` [-p | --pool *pool-name*] + List rbd groups. + +:command:`group rename` *src-group-spec* *dest-group-spec* + Rename a group. Note: rename across pools is not supported. + +:command:`group rm` *group-spec* + Delete a group. + +:command:`group snap create` *group-snap-spec* + Make a snapshot of a group. + +:command:`group snap list` *group-spec* + List snapshots of a group. + +:command:`group snap rm` *group-snap-spec* + Remove a snapshot from a group. + +:command:`group snap rename` *group-snap-spec* *snap-name* + Rename group's snapshot. + +:command:`group snap rollback` *group-snap-spec* + Rollback group to snapshot. + +:command:`image-meta get` *image-spec* *key* + Get metadata value with the key. + +:command:`image-meta list` *image-spec* + Show metadata held on the image. The first column is the key + and the second column is the value. + +:command:`image-meta remove` *image-spec* *key* + Remove metadata key with the value. + +:command:`image-meta set` *image-spec* *key* *value* + Set metadata key with the value. They will displayed in `image-meta list`. + +:command:`import` [--export-format *format (1 or 2)*] [--image-format *format-id*] [--object-size *size-in-B/K/M*] [--stripe-unit *size-in-B/K/M* --stripe-count *num*] [--image-feature *feature-name*]... [--image-shared] *src-path* [*image-spec*] + Create a new image and imports its data from path (use - for + stdin). The import operation will try to create sparse rbd images + if possible. For import from stdin, the sparsification unit is + the data block size of the destination image (object size). + + The --stripe-unit and --stripe-count arguments are optional, but must be + used together. + + The --export-format accepts '1' or '2' currently. Format 2 allow us to import not only the content + of image, but also the snapshots and other properties, such as image_order, features. + +:command:`import-diff` *src-path* *image-spec* + Import an incremental diff of an image and applies it to the current image. If the diff + was generated relative to a start snapshot, we verify that snapshot already exists before + continuing. If there was an end snapshot we verify it does not already exist before + applying the changes, and create the snapshot when we are done. + +:command:`info` *image-spec* | *snap-spec* + Will dump information (such as size and object size) about a specific rbd image. + If image is a clone, information about its parent is also displayed. + If a snapshot is specified, whether it is protected is shown as well. + +:command:`journal client disconnect` *journal-spec* + Flag image journal client as disconnected. + +:command:`journal export` [--verbose] [--no-error] *src-journal-spec* *path-name* + Export image journal to path (use - for stdout). It can be make a backup + of the image journal especially before attempting dangerous operations. + + Note that this command may not always work if the journal is badly corrupted. + +:command:`journal import` [--verbose] [--no-error] *path-name* *dest-journal-spec* + Import image journal from path (use - for stdin). + +:command:`journal info` *journal-spec* + Show information about image journal. + +:command:`journal inspect` [--verbose] *journal-spec* + Inspect and report image journal for structural errors. + +:command:`journal reset` *journal-spec* + Reset image journal. + +:command:`journal status` *journal-spec* + Show status of image journal. + +:command:`lock add` [--shared *lock-tag*] *image-spec* *lock-id* + Lock an image. The lock-id is an arbitrary name for the user's + convenience. By default, this is an exclusive lock, meaning it + will fail if the image is already locked. The --shared option + changes this behavior. Note that locking does not affect + any operation other than adding a lock. It does not + protect an image from being deleted. + +:command:`lock ls` *image-spec* + Show locks held on the image. The first column is the locker + to use with the `lock remove` command. + +:command:`lock rm` *image-spec* *lock-id* *locker* + Release a lock on an image. The lock id and locker are + as output by lock ls. + +:command:`ls` [-l | --long] [*pool-name*] + Will list all rbd images listed in the rbd_directory object. With + -l, also show snapshots, and use longer-format output including + size, parent (if clone), format, etc. + +:command:`merge-diff` *first-diff-path* *second-diff-path* *merged-diff-path* + Merge two continuous incremental diffs of an image into one single diff. The + first diff's end snapshot must be equal with the second diff's start snapshot. + The first diff could be - for stdin, and merged diff could be - for stdout, which + enables multiple diff files to be merged using something like + 'rbd merge-diff first second - | rbd merge-diff - third result'. Note this command + currently only support the source incremental diff with stripe_count == 1 + +:command:`migration abort` *image-spec* + Cancel image migration. This step may be run after successful or + failed migration prepare or migration execute steps and returns the + image to its initial (before migration) state. All modifications to + the destination image are lost. + +:command:`migration commit` *image-spec* + Commit image migration. This step is run after a successful migration + prepare and migration execute steps and removes the source image data. + +:command:`migration execute` *image-spec* + Execute image migration. This step is run after a successful migration + prepare step and copies image data to the destination. + +:command:`migration prepare` [--order *order*] [--object-size *object-size*] [--image-feature *image-feature*] [--image-shared] [--stripe-unit *stripe-unit*] [--stripe-count *stripe-count*] [--data-pool *data-pool*] *src-image-spec* [*dest-image-spec*] + Prepare image migration. This is the first step when migrating an + image, i.e. changing the image location, format or other + parameters that can't be changed dynamically. The destination can + match the source, and in this case *dest-image-spec* can be omitted. + After this step the source image is set as a parent of the + destination image, and the image is accessible in copy-on-write mode + by its destination spec. + +:command:`mirror image demote` *image-spec* + Demote a primary image to non-primary for RBD mirroring. + +:command:`mirror image disable` [--force] *image-spec* + Disable RBD mirroring for an image. If the mirroring is + configured in ``image`` mode for the image's pool, then it + can be explicitly disabled mirroring for each image within + the pool. + +:command:`mirror image enable` *image-spec* + Enable RBD mirroring for an image. If the mirroring is + configured in ``image`` mode for the image's pool, then it + can be explicitly enabled mirroring for each image within + the pool. + + This requires the RBD journaling feature is enabled. + +:command:`mirror image promote` [--force] *image-spec* + Promote a non-primary image to primary for RBD mirroring. + +:command:`mirror image resync` *image-spec* + Force resync to primary image for RBD mirroring. + +:command:`mirror image status` *image-spec* + Show RBD mirroring status for an image. + +:command:`mirror pool demote` [*pool-name*] + Demote all primary images within a pool to non-primary. + Every mirroring enabled image will demoted in the pool. + +:command:`mirror pool disable` [*pool-name*] + Disable RBD mirroring by default within a pool. When mirroring + is disabled on a pool in this way, mirroring will also be + disabled on any images (within the pool) for which mirroring + was enabled explicitly. + +:command:`mirror pool enable` [*pool-name*] *mode* + Enable RBD mirroring by default within a pool. + The mirroring mode can either be ``pool`` or ``image``. + If configured in ``pool`` mode, all images in the pool + with the journaling feature enabled are mirrored. + If configured in ``image`` mode, mirroring needs to be + explicitly enabled (by ``mirror image enable`` command) + on each image. + +:command:`mirror pool info` [*pool-name*] + Show information about the pool mirroring configuration. + It includes mirroring mode, peer UUID, remote cluster name, + and remote client name. + +:command:`mirror pool peer add` [*pool-name*] *remote-cluster-spec* + Add a mirroring peer to a pool. + *remote-cluster-spec* is [*remote client name*\ @\ ]\ *remote cluster name*. + + The default for *remote client name* is "client.admin". + + This requires mirroring mode is enabled. + +:command:`mirror pool peer remove` [*pool-name*] *uuid* + Remove a mirroring peer from a pool. The peer uuid is available + from ``mirror pool info`` command. + +:command:`mirror pool peer set` [*pool-name*] *uuid* *key* *value* + Update mirroring peer settings. + The key can be either ``client`` or ``cluster``, and the value + is corresponding to remote client name or remote cluster name. + +:command:`mirror pool promote` [--force] [*pool-name*] + Promote all non-primary images within a pool to primary. + Every mirroring enabled image will promoted in the pool. + +:command:`mirror pool status` [--verbose] [*pool-name*] + Show status for all mirrored images in the pool. + With --verbose, also show additionally output status + details for every mirroring image in the pool. + +:command:`mv` *src-image-spec* *dest-image-spec* + Rename an image. Note: rename across pools is not supported. + +:command:`namespace create` *pool-name*/*namespace-name* + Create a new image namespace within the pool. + +:command:`namespace list` *pool-name* + List image namespaces defined within the pool. + +:command:`namespace remove` *pool-name*/*namespace-name* + Remove an empty image namespace from the pool. + +:command:`object-map check` *image-spec* | *snap-spec* + Verify the object map is correct. + +:command:`object-map rebuild` *image-spec* | *snap-spec* + Rebuild an invalid object map for the specified image. An image snapshot can be + specified to rebuild an invalid object map for a snapshot. + +:command:`pool init` [*pool-name*] [--force] + Initialize pool for use by RBD. Newly created pools must initialized + prior to use. + +:command:`resize` (-s | --size *size-in-M/G/T*) [--allow-shrink] *image-spec* + Resize rbd image. The size parameter also needs to be specified. + The --allow-shrink option lets the size be reduced. + +:command:`rm` *image-spec* + Delete an rbd image (including all data blocks). If the image has + snapshots, this fails and nothing is deleted. + +:command:`snap create` *snap-spec* + Create a new snapshot. Requires the snapshot name parameter specified. + +:command:`snap limit clear` *image-spec* + Remove any previously set limit on the number of snapshots allowed on + an image. + +:command:`snap limit set` [--limit] *limit* *image-spec* + Set a limit for the number of snapshots allowed on an image. + +:command:`snap ls` *image-spec* + Dump the list of snapshots inside a specific image. + +:command:`snap protect` *snap-spec* + Protect a snapshot from deletion, so that clones can be made of it + (see `rbd clone`). Snapshots must be protected before clones are made; + protection implies that there exist dependent cloned children that + refer to this snapshot. `rbd clone` will fail on a nonprotected + snapshot. + + This requires image format 2. + +:command:`snap purge` *image-spec* + Remove all unprotected snapshots from an image. + +:command:`snap rename` *src-snap-spec* *dest-snap-spec* + Rename a snapshot. Note: rename across pools and images is not supported. + +:command:`snap rm` [--force] *snap-spec* + Remove the specified snapshot. + +:command:`snap rollback` *snap-spec* + Rollback image content to snapshot. This will iterate through the entire blocks + array and update the data head content to the snapshotted version. + +:command:`snap unprotect` *snap-spec* + Unprotect a snapshot from deletion (undo `snap protect`). If cloned + children remain, `snap unprotect` fails. (Note that clones may exist + in different pools than the parent snapshot.) + + This requires image format 2. + +:command:`sparsify` [--sparse-size *sparse-size*] *image-spec* + Reclaim space for zeroed image extents. The default sparse size is + 4096 bytes and can be changed via --sparse-size option with the + following restrictions: it should be power of two, not less than + 4096, and not larger image object size. + +:command:`status` *image-spec* + Show the status of the image, including which clients have it open. + +:command:`trash ls` [*pool-name*] + List all entries from trash. + +:command:`trash mv` *image-spec* + Move an image to the trash. Images, even ones actively in-use by + clones, can be moved to the trash and deleted at a later time. + +:command:`trash purge` [*pool-name*] + Remove all expired images from trash. + +:command:`trash restore` *image-id* + Restore an image from trash. + +:command:`trash rm` *image-id* + Delete an image from trash. If image deferment time has not expired + you can not removed it unless use force. But an actively in-use by clones + or has snapshots can not be removed. + +:command:`watch` *image-spec* + Watch events on image. + +Image, snap, group and journal specs +==================================== + +| *image-spec* is [*pool-name*/[*namespace-name*/]]\ *image-name* +| *snap-spec* is [*pool-name*/[*namespace-name*/]]\ *image-name*\ @\ *snap-name* +| *group-spec* is [*pool-name*/[*namespace-name*/]]\ *group-name* +| *group-snap-spec* is [*pool-name*/[*namespace-name*/]]\ *group-name*\ @\ *snap-name* +| *journal-spec* is [*pool-name*/[*namespace-name*/]]\ *journal-name* + +The default for *pool-name* is "rbd" and *namespace-name* is "". If an image +name contains a slash character ('/'), *pool-name* is required. + +The *journal-name* is *image-id*. + +You may specify each name individually, using --pool, --namespace, --image, and +--snap options, but this is discouraged in favor of the above spec syntax. + +Striping +======== + +RBD images are striped over many objects, which are then stored by the +Ceph distributed object store (RADOS). As a result, read and write +requests for the image are distributed across many nodes in the +cluster, generally preventing any single node from becoming a +bottleneck when individual images get large or busy. + +The striping is controlled by three parameters: + +.. option:: object-size + + The size of objects we stripe over is a power of two. It will be rounded up the nearest power of two. + The default object size is 4 MB, smallest is 4K and maximum is 32M. + +.. option:: stripe_unit + + Each [*stripe_unit*] contiguous bytes are stored adjacently in the same object, before we move on + to the next object. + +.. option:: stripe_count + + After we write [*stripe_unit*] bytes to [*stripe_count*] objects, we loop back to the initial object + and write another stripe, until the object reaches its maximum size. At that point, + we move on to the next [*stripe_count*] objects. + +By default, [*stripe_unit*] is the same as the object size and [*stripe_count*] is 1. Specifying a different +[*stripe_unit*] requires that the STRIPINGV2 feature be supported (added in Ceph v0.53) and format 2 images be +used. + + +Kernel rbd (krbd) options +========================= + +Most of these options are useful mainly for debugging and benchmarking. The +default values are set in the kernel and may therefore depend on the version of +the running kernel. + +Per client instance `rbd device map` options: + +* fsid=aaaaaaaa-bbbb-cccc-dddd-eeeeeeeeeeee - FSID that should be assumed by + the client. + +* ip=a.b.c.d[:p] - IP and, optionally, port the client should use. + +* share - Enable sharing of client instances with other mappings (default). + +* noshare - Disable sharing of client instances with other mappings. + +* crc - Enable CRC32C checksumming for msgr1 on-the-wire protocol (default). + For msgr2.1 protocol this option is ignored: full checksumming is always on + in 'crc' mode and always off in 'secure' mode. + +* nocrc - Disable CRC32C checksumming for msgr1 on-the-wire protocol. Note + that only payload checksumming is disabled, header checksumming is always on. + For msgr2.1 protocol this option is ignored. + +* cephx_require_signatures - Require msgr1 message signing feature (since 3.19, + default). This option is deprecated and will be removed in the future as the + feature has been supported since the Bobtail release. + +* nocephx_require_signatures - Don't require msgr1 message signing feature + (since 3.19). This option is deprecated and will be removed in the future. + +* tcp_nodelay - Disable Nagle's algorithm on client sockets (since 4.0, + default). + +* notcp_nodelay - Enable Nagle's algorithm on client sockets (since 4.0). + +* cephx_sign_messages - Enable message signing for msgr1 on-the-wire protocol + (since 4.4, default). For msgr2.1 protocol this option is ignored: message + signing is built into 'secure' mode and not offered in 'crc' mode. + +* nocephx_sign_messages - Disable message signing for msgr1 on-the-wire protocol + (since 4.4). For msgr2.1 protocol this option is ignored. + +* mount_timeout=x - A timeout on various steps in `rbd device map` and + `rbd device unmap` sequences (default is 60 seconds). In particular, + since 4.2 this can be used to ensure that `rbd device unmap` eventually + times out when there is no network connection to a cluster. + +* osdkeepalive=x - OSD keepalive timeout (default is 5 seconds). + +* osd_idle_ttl=x - OSD idle TTL (default is 60 seconds). + +Per mapping (block device) `rbd device map` options: + +* rw - Map the image read-write (default). Overridden by --read-only. + +* ro - Map the image read-only. Equivalent to --read-only. + +* queue_depth=x - queue depth (since 4.2, default is 128 requests). + +* lock_on_read - Acquire exclusive lock on reads, in addition to writes and + discards (since 4.9). + +* exclusive - Disable automatic exclusive lock transitions (since 4.12). + Equivalent to --exclusive. + +* lock_timeout=x - A timeout on waiting for the acquisition of exclusive lock + (since 4.17, default is 0 seconds, meaning no timeout). + +* notrim - Turn off discard and write zeroes offload support to avoid + deprovisioning a fully provisioned image (since 4.17). When enabled, discard + requests will fail with -EOPNOTSUPP, write zeroes requests will fall back to + manually zeroing. + +* abort_on_full - Fail write requests with -ENOSPC when the cluster is full or + the data pool reaches its quota (since 5.0). The default behaviour is to + block until the full condition is cleared. + +* alloc_size - Minimum allocation unit of the underlying OSD object store + backend (since 5.1, default is 64K bytes). This is used to round off and + drop discards that are too small. For bluestore, the recommended setting is + bluestore_min_alloc_size (typically 64K for hard disk drives and 16K for + solid-state drives). For filestore with filestore_punch_hole = false, the + recommended setting is image object size (typically 4M). + +* ms_mode=legacy - Use msgr1 on-the-wire protocol (since 5.11, default). + +* ms_mode=crc - Use msgr2.1 on-the-wire protocol, select 'crc' mode, also + referred to as plain mode (since 5.11). If the daemon denies 'crc' mode, + fail the connection. + +* ms_mode=secure - Use msgr2.1 on-the-wire protocol, select 'secure' mode + (since 5.11). 'secure' mode provides full in-transit encryption ensuring + both confidentiality and authenticity. If the daemon denies 'secure' mode, + fail the connection. + +* ms_mode=prefer-crc - Use msgr2.1 on-the-wire protocol, select 'crc' + mode (since 5.11). If the daemon denies 'crc' mode in favor of 'secure' + mode, agree to 'secure' mode. + +* ms_mode=prefer-secure - Use msgr2.1 on-the-wire protocol, select 'secure' + mode (since 5.11). If the daemon denies 'secure' mode in favor of 'crc' + mode, agree to 'crc' mode. + +* udev - Wait for udev device manager to finish executing all matching + "add" rules and release the device before exiting (default). This option + is not passed to the kernel. + +* noudev - Don't wait for udev device manager. When enabled, the device may + not be fully usable immediately on exit. + +`rbd device unmap` options: + +* force - Force the unmapping of a block device that is open (since 4.9). The + driver will wait for running requests to complete and then unmap; requests + sent to the driver after initiating the unmap will be failed. + +* udev - Wait for udev device manager to finish executing all matching + "remove" rules and clean up after the device before exiting (default). + This option is not passed to the kernel. + +* noudev - Don't wait for udev device manager. + + +Examples +======== + +To create a new rbd image that is 100 GB:: + + rbd create mypool/myimage --size 102400 + +To use a non-default object size (8 MB):: + + rbd create mypool/myimage --size 102400 --object-size 8M + +To delete an rbd image (be careful!):: + + rbd rm mypool/myimage + +To create a new snapshot:: + + rbd snap create mypool/myimage@mysnap + +To create a copy-on-write clone of a protected snapshot:: + + rbd clone mypool/myimage@mysnap otherpool/cloneimage + +To see which clones of a snapshot exist:: + + rbd children mypool/myimage@mysnap + +To delete a snapshot:: + + rbd snap rm mypool/myimage@mysnap + +To map an image via the kernel with cephx enabled:: + + rbd device map mypool/myimage --id admin --keyfile secretfile + +To map an image via the kernel with different cluster name other than default *ceph*:: + + rbd device map mypool/myimage --cluster cluster-name + +To unmap an image:: + + rbd device unmap /dev/rbd0 + +To create an image and a clone from it:: + + rbd import --image-format 2 image mypool/parent + rbd snap create mypool/parent@snap + rbd snap protect mypool/parent@snap + rbd clone mypool/parent@snap otherpool/child + +To create an image with a smaller stripe_unit (to better distribute small writes in some workloads):: + + rbd create mypool/myimage --size 102400 --stripe-unit 65536B --stripe-count 16 + +To change an image from one image format to another, export it and then +import it as the desired image format:: + + rbd export mypool/myimage@snap /tmp/img + rbd import --image-format 2 /tmp/img mypool/myimage2 + +To lock an image for exclusive use:: + + rbd lock add mypool/myimage mylockid + +To release a lock:: + + rbd lock remove mypool/myimage mylockid client.2485 + +To list images from trash:: + + rbd trash ls mypool + +To defer delete an image (use *--expires-at* to set expiration time, default is now):: + + rbd trash mv mypool/myimage --expires-at "tomorrow" + +To delete an image from trash (be careful!):: + + rbd trash rm mypool/myimage-id + +To force delete an image from trash (be careful!):: + + rbd trash rm mypool/myimage-id --force + +To restore an image from trash:: + + rbd trash restore mypool/myimage-id + +To restore an image from trash and rename it:: + + rbd trash restore mypool/myimage-id --image mynewimage + + +Availability +============ + +**rbd** is part of Ceph, a massively scalable, open-source, distributed storage system. Please refer to +the Ceph documentation at http://ceph.com/docs for more information. + + +See also +======== + +:doc:`ceph <ceph>`\(8), +:doc:`rados <rados>`\(8) |