Provided by: ceph-volume_19.2.1-0ubuntu3_all 
NAME
ceph-volume - Ceph OSD deployment and inspection tool
SYNOPSIS
ceph-volume [-h] [--cluster CLUSTER] [--log-level LOG_LEVEL] [--log-path LOG_PATH]
ceph-volume inventory
ceph-volume lvm [ trigger | create | activate | prepare | zap | list | batch | new-wal | new-db | migrate
]
ceph-volume simple [ trigger | scan | activate ]
DESCRIPTION
ceph-volume is a single purpose command line tool to deploy logical volumes as OSDs, trying to maintain a
similar API to ceph-disk when preparing, activating, and creating OSDs.
It deviates from ceph-disk by not interacting or relying on the udev rules that come installed for Ceph.
These rules allow automatic detection of previously setup devices that are in turn fed into ceph-disk to
activate them.
COMMANDS
inventory
This subcommand provides information about a host's physical disc inventory and reports metadata about
these discs. Among this metadata one can find disc specific data items (like model, size, rotational or
solid state) as well as data items specific to ceph using a device, such as if it is available for use
with ceph or if logical volumes are present.
Examples:
ceph-volume inventory
ceph-volume inventory /dev/sda
ceph-volume inventory --format json-pretty
Optional arguments:
-h, --help
show the help message and exit
--format
report format, valid values are plain (default), json and json-pretty
lvm
By making use of LVM tags, the lvm sub-command is able to store and later re-discover and query devices
associated with OSDs so that they can later activated.
Subcommands:
batch
Creates OSDs from a list of devices using a bluestore (default) setup. It will create all necessary
volume groups and logical volumes required to have a working OSD.
Example usage with three devices:
ceph-volume lvm batch --bluestore /dev/sda /dev/sdb /dev/sdc
Optional arguments:
-h, --help
show the help message and exit
--bluestore
Use the bluestore objectstore (default)
--yes Skip the report and prompt to continue provisioning
--prepare
Only prepare OSDs, do not activate
--dmcrypt
Enable encryption for the underlying OSD devices
--crush-device-class
Define a CRUSH device class to assign the OSD to
--no-systemd
Do not enable or create any systemd units
--osds-per-device
Provision more than 1 (the default) OSD per device
--report
Report what the potential outcome would be for the current input (requires devices to be passed
in)
--format
Output format when reporting (used along with --report), can be one of 'pretty' (default) or
'json'
--block-db-size
Set (or override) the "bluestore_block_db_size" value, in bytes
--journal-size
Override the "osd_journal_size" value, in megabytes
Required positional arguments:
<DEVICE>
Full path to a raw device, like /dev/sda. Multiple <DEVICE> paths can be passed in.
activate
Enables a systemd unit that persists the OSD ID and its UUID (also called fsid in Ceph CLI tools), so
that at boot time it can understand what OSD is enabled and needs to be mounted.
Usage:
ceph-volume lvm activate --bluestore <osd id> <osd fsid>
Optional Arguments:
-h, --help
show the help message and exit
--auto-detect-objectstore
Automatically detect the objectstore by inspecting the OSD
--bluestore
bluestore objectstore (default)
--all Activate all OSDs found in the system
--no-systemd
Skip creating and enabling systemd units and starting of OSD services
Multiple OSDs can be activated at once by using the (idempotent) --all flag:
ceph-volume lvm activate --all
prepare
Prepares a logical volume to be used as an OSD and journal using a bluestore (default) setup. It will
not create or modify the logical volumes except for adding extra metadata.
Usage:
ceph-volume lvm prepare --bluestore --data <data lv> --journal <journal device>
Optional arguments:
-h, --help
show the help message and exit
--journal JOURNAL
logical group name, path to a logical volume, or path to a device
--bluestore
Use the bluestore objectstore (default)
--block.wal
Path to a bluestore block.wal logical volume or partition
--block.db
Path to a bluestore block.db logical volume or partition
--dmcrypt
Enable encryption for the underlying OSD devices
--osd-id OSD_ID
Reuse an existing OSD id
--osd-fsid OSD_FSID
Reuse an existing OSD fsid
--crush-device-class
Define a CRUSH device class to assign the OSD to
Required arguments:
--data A logical group name or a path to a logical volume
For encrypting an OSD, the --dmcrypt flag must be added when preparing (also supported in the create
sub-command).
create
Wraps the two-step process to provision a new osd (calling prepare first and then activate) into a single
one. The reason to prefer prepare and then activate is to gradually introduce new OSDs into a cluster,
and avoiding large amounts of data being rebalanced.
The single-call process unifies exactly what prepare and activate do, with the convenience of doing it
all at once. Flags and general usage are equivalent to those of the prepare and activate subcommand.
trigger
This subcommand is not meant to be used directly, and it is used by systemd so that it proxies input to
ceph-volume lvm activate by parsing the input from systemd, detecting the UUID and ID associated with an
OSD.
Usage:
ceph-volume lvm trigger <SYSTEMD-DATA>
The systemd "data" is expected to be in the format of:
<OSD ID>-<OSD UUID>
The lvs associated with the OSD need to have been prepared previously, so that all needed tags and
metadata exist.
Positional arguments:
<SYSTEMD_DATA>
Data from a systemd unit containing ID and UUID of the OSD.
list
List devices or logical volumes associated with Ceph. An association is determined if a device has
information relating to an OSD. This is verified by querying LVM's metadata and correlating it with
devices.
The lvs associated with the OSD need to have been prepared previously by ceph-volume so that all needed
tags and metadata exist.
Usage:
ceph-volume lvm list
List a particular device, reporting all metadata about it:
ceph-volume lvm list /dev/sda1
List a logical volume, along with all its metadata (vg is a volume group, and lv the logical volume
name):
ceph-volume lvm list {vg/lv}
Positional arguments:
<DEVICE>
Either in the form of vg/lv for logical volumes, /path/to/sda1 or /path/to/sda for regular
devices.
zap
Zaps the given logical volume or partition. If given a path to a logical volume it must be in the format
of vg/lv. Any file systems present on the given lv or partition will be removed and all data will be
purged.
However, the lv or partition will be kept intact.
Usage, for logical volumes:
ceph-volume lvm zap {vg/lv}
Usage, for logical partitions:
ceph-volume lvm zap /dev/sdc1
For full removal of the device use the --destroy flag (allowed for all device types):
ceph-volume lvm zap --destroy /dev/sdc1
Multiple devices can be removed by specifying the OSD ID and/or the OSD FSID:
ceph-volume lvm zap --destroy --osd-id 1
ceph-volume lvm zap --destroy --osd-id 1 --osd-fsid C9605912-8395-4D76-AFC0-7DFDAC315D59
Positional arguments:
<DEVICE>
Either in the form of vg/lv for logical volumes, /path/to/sda1 or /path/to/sda for regular
devices.
new-wal
Attaches the given logical volume to OSD as a WAL. Logical volume name format is vg/lv. Fails if OSD has
already got attached WAL.
Usage:
ceph-volume lvm new-wal --osd-id OSD_ID --osd-fsid OSD_FSID --target <target lv>
Optional arguments:
-h, --help
show the help message and exit
--no-systemd
Skip checking OSD systemd unit
Required arguments:
--target
logical volume name to attach as WAL
new-db
Attaches the given logical volume to OSD as a DB. Logical volume name format is vg/lv. Fails if OSD has
already got attached DB.
Usage:
ceph-volume lvm new-db --osd-id OSD_ID --osd-fsid OSD_FSID --target <target lv>
Optional arguments:
-h, --help
show the help message and exit
--no-systemd
Skip checking OSD systemd unit
Required arguments:
--target
logical volume name to attach as DB
migrate
Moves BlueFS data from source volume(s) to the target one, source volumes (except the main, i.e. data or
block one) are removed on success. LVM volumes are permitted for Target only, both already attached or
new one. In the latter case it is attached to the OSD replacing one of the source devices. Following
replacement rules apply (in the order of precedence, stop on the first match):
• if source list has DB volume - target device replaces it.
• if source list has WAL volume - target device replace it.
• if source list has slow volume only - operation is not permitted, requires explicit allocation via
new-db/new-wal command.
Usage:
ceph-volume lvm migrate --osd-id OSD_ID --osd-fsid OSD_FSID --target <target lv> --from {data|db|wal} [{data|db|wal} ...]
Optional arguments:
-h, --help
show the help message and exit
--no-systemd
Skip checking OSD systemd unit
Required arguments:
--from list of source device type names
--target
logical volume to move data to
simple
Scan legacy OSD directories or data devices that may have been created by ceph-disk, or manually.
Subcommands:
activate
Enables a systemd unit that persists the OSD ID and its UUID (also called fsid in Ceph CLI tools), so
that at boot time it can understand what OSD is enabled and needs to be mounted, while reading
information that was previously created and persisted at /etc/ceph/osd/ in JSON format.
Usage:
ceph-volume simple activate --bluestore <osd id> <osd fsid>
Optional Arguments:
-h, --help
show the help message and exit
--bluestore
bluestore objectstore (default)
NOTE:
It requires a matching JSON file with the following format:
/etc/ceph/osd/<osd id>-<osd fsid>.json
scan
Scan a running OSD or data device for an OSD for metadata that can later be used to activate and manage
the OSD with ceph-volume. The scan method will create a JSON file with the required information plus
anything found in the OSD directory as well.
Optionally, the JSON blob can be sent to stdout for further inspection.
Usage on all running OSDs:
ceph-volume simple scan
Usage on data devices:
ceph-volume simple scan <data device>
Running OSD directories:
ceph-volume simple scan <path to osd dir>
Optional arguments:
-h, --help
show the help message and exit
--stdout
Send the JSON blob to stdout
--force
If the JSON file exists at destination, overwrite it
Optional Positional arguments:
<DATA DEVICE or OSD DIR>
Actual data partition or a path to the running OSD
trigger
This subcommand is not meant to be used directly, and it is used by systemd so that it proxies input to
ceph-volume simple activate by parsing the input from systemd, detecting the UUID and ID associated with
an OSD.
Usage:
ceph-volume simple trigger <SYSTEMD-DATA>
The systemd "data" is expected to be in the format of:
<OSD ID>-<OSD UUID>
The JSON file associated with the OSD need to have been persisted previously by a scan (or manually), so
that all needed metadata can be used.
Positional arguments:
<SYSTEMD_DATA>
Data from a systemd unit containing ID and UUID of the OSD.
AVAILABILITY
ceph-volume is part of Ceph, a massively scalable, open-source, distributed storage system. Please refer
to the documentation at http://docs.ceph.com/ for more information.
SEE ALSO
ceph-osd(8),
COPYRIGHT
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 CEPH-VOLUME(8)