NAME¶

lvcreate — Create a logical volume

SYNOPSIS¶

lvcreate option_args position_args
[ option_args ]
[ position_args ]

-a|--activate y|n|ay
--addtag Tag
--alloc contiguous|cling|cling_by_tags|normal|anywhere|inherit
-A|--autobackup y|n
-H|--cache
--cachedevice PV
--cachemetadataformat auto|1|2
--cachemode writethrough|writeback|passthrough
--cachepolicy String
--cachepool LV
--cachesettings String
--cachesize Size[m|UNIT]
--cachevol LV
-c|--chunksize Size[k|UNIT]
--commandprofile String
--compression y|n
--config String
-C|--contiguous y|n
-d|--debug
--deduplication y|n
--devices PV
--devicesfile String
--discards passdown|nopassdown|ignore
--driverloaded y|n
--errorwhenfull y|n
-l|--extents Number[PERCENT]
-h|--help
-K|--ignoreactivationskip
--ignoremonitoring
--journal String
--lockopt String
--longhelp
-j|--major Number
--[raid]maxrecoveryrate Size[k|UNIT]
--metadataprofile String
--minor Number
--[raid]minrecoveryrate Size[k|UNIT]
--mirrorlog core|disk
-m|--mirrors Number
--monitor y|n
-n|--name String
--nohints
--nolocking
--nosync
--noudevsync
-p|--permission rw|r
-M|--persistent y|n
--poolmetadatasize Size[m|UNIT]
--poolmetadataspare y|n
--profile String
-q|--quiet
--raidintegrity y|n
--raidintegrityblocksize Number
--raidintegritymode String
-r|--readahead auto|none|Number
-R|--regionsize Size[m|UNIT]
--reportformat basic|json
-k|--setactivationskip y|n
--setautoactivation y|n
-L|--size Size[m|UNIT]
-s|--snapshot
-i|--stripes Number
-I|--stripesize Size[k|UNIT]
-t|--test
-T|--thin
--thinpool LV
--type linear|striped|snapshot|raid|mirror|thin|thin-pool|vdo|vdo-pool|cache|cache-pool|writecache
--vdo
--vdopool LV
--vdosettings String
-v|--verbose
--version
-V|--virtualsize Size[m|UNIT]
-W|--wipesignatures y|n
-y|--yes
-Z|--zero y|n

DESCRIPTION¶

lvcreate creates a new LV in a VG. For standard LVs, this requires allocating logical extents from the VG's free physical extents. If there is not enough free space, the VG can be extended with other PVs (vgextend(8)), or existing LVs can be reduced or removed (lvremove(8), lvreduce(8)).

To control which PVs a new LV will use, specify one or more PVs as position args at the end of the command line. lvcreate will allocate physical extents only from the specified PVs.

lvcreate can also create snapshots of existing LVs, e.g. for backup purposes. The data in a new snapshot LV represents the content of the original LV from the time the snapshot was created.

RAID LVs can be created by specifying an LV type when creating the LV (see lvmraid(7)). Different RAID levels require different numbers of unique PVs be available in the VG for allocation.

Thin pools (for thin provisioning) and cache pools (for caching) are represented by special LVs with types thin-pool and cache-pool (see lvmthin(7) and lvmcache(7)). The pool LVs are not usable as standard block devices, but the LV names act as references to the pools.

Thin LVs are thinly provisioned from a thin pool, and are created with a virtual size rather than a physical size. A cache LV is the combination of a standard LV with a cache pool, used to cache active portions of the LV to improve performance.

VDO LVs are also provisioned volumes from a VDO pool, and are created with a virtual size rather than a physical size (see lvmvdo(7)).

USAGE¶

Create a linear LV.

lvcreate -L|--size Size[m|UNIT] VG

—

Create a striped LV.

lvcreate -i|--stripes Number -L|--size Size[m|UNIT] VG

—

Create a raid1 or mirror LV.

lvcreate -m|--mirrors Number -L|--size Size[m|UNIT] VG

—

Create a raid LV (a specific raid level must be used, e.g. raid1).

lvcreate --type raid -L|--size Size[m|UNIT] VG

—

Create a raid10 LV.

lvcreate -m|--mirrors Number -i|--stripes Number

—

Create a COW snapshot LV of an origin LV.

lvcreate -s|--snapshot -L|--size Size[m|UNIT] LV

—

Create a thin pool.

lvcreate --type thin-pool -L|--size Size[m|UNIT] VG

—

Create a cache pool.

lvcreate --type cache-pool -L|--size Size[m|UNIT] VG

—

Create a thin LV in a thin pool.

lvcreate -V|--virtualsize Size[m|UNIT] --thinpool LV VG

—

Create a thin LV that is a snapshot of an existing thin LV.

lvcreate -s|--snapshot LV1

—

Create a thin LV that is a snapshot of an external origin LV.

lvcreate --type thin --thinpool LV LV

—

Create a LV that returns VDO when used.

lvcreate --type vdo -L|--size Size[m|UNIT] VG

—

Create a new LV, then attach the specified cachepool
which converts the new LV to type cache.

lvcreate --type cache -L|--size Size[m|UNIT]

—

Create a new LV, then attach the specified cachevol
which converts the new LV to type cache.

lvcreate --type cache -L|--size Size[m|UNIT]

—

Create a new LV, then attach a cachevol created from
the specified cache device, which converts the
new LV to type cache.

lvcreate --type cache -L|--size Size[m|UNIT]

—

Create a new LV, then attach the specified cachevol
which converts the new LV to type writecache.

lvcreate --type writecache -L|--size Size[m|UNIT]

—

Create a new LV, then attach a cachevol created from
the specified cache device, which converts the
new LV to type writecache.

lvcreate --type writecache -L|--size Size[m|UNIT]

—

Common options for command:

Common options for lvm:

OPTIONS¶

-a|--activate y|n|ay
Controls the active state of the new LV. y makes the LV active, or available. New LVs are made active by default. n makes the LV inactive, or unavailable, only when possible. In some cases, creating an LV requires it to be active. For example, COW snapshots of an active origin LV can only be created in the active state (this does not apply to thin snapshots). The --zero option normally requires the LV to be active. If autoactivation ay is used, the LV is only activated if it matches an item in lvm.conf(5) activation/auto_activation_volume_list. ay implies --zero n and --wipesignatures n. See lvmlockd(8) for more information about activation options for shared VGs.

--addtag Tag
Adds a tag to a PV, VG or LV. This option can be repeated to add multiple tags at once. See lvm(8) for information about tags.

--alloc contiguous|cling|cling_by_tags|normal|anywhere|inherit
Determines the allocation policy when a command needs to allocate Physical Extents (PEs) from the VG. Each VG and LV has an allocation policy which can be changed with vgchange/lvchange, or overridden on the command line. normal applies common sense rules such as not placing parallel stripes on the same PV. inherit applies the VG policy to an LV. contiguous requires new PEs be placed adjacent to existing PEs. cling places new PEs on the same PV as existing PEs in the same stripe of the LV. If there are sufficient PEs for an allocation, but normal does not use them, anywhere will use them even if it reduces performance, e.g. by placing two stripes on the same PV. Optional positional PV args on the command line can also be used to limit which PVs the command will use for allocation. See lvm(8) for more information about allocation.

-A|--autobackup y|n
Specifies if metadata should be backed up automatically after a change. Enabling this is strongly advised! See vgcfgbackup(8) for more information.

-H|--cache
Specifies the command is handling a cache LV or cache pool. See --type cache and --type cache-pool. See lvmcache(7) for more information about LVM caching.

--cachedevice PV
The name of a device to use for a cache.

--cachemetadataformat auto|1|2
Specifies the cache metadata format used by cache target.

--cachemode writethrough|writeback|passthrough
Specifies when writes to a cache LV should be considered complete. writeback considers a write complete as soon as it is stored in the cache pool. writethough considers a write complete only when it has been stored in both the cache pool and on the origin LV. While writethrough may be slower for writes, it is more resilient if something should happen to a device associated with the cache pool LV. With passthrough, all reads are served from the origin LV (all reads miss the cache) and all writes are forwarded to the origin LV; additionally, write hits cause cache block invalidates. See lvmcache(7) for more information.

--cachepolicy String
Specifies the cache policy for a cache LV. See lvmcache(7) for more information.

--cachepool LV
The name of a cache pool.

--cachesettings String
Specifies tunable values for a cache LV in "Key = Value" form. Repeat this option to specify multiple values. (The default values should usually be adequate.) The special string value default switches settings back to their default kernel values and removes them from the list of settings stored in LVM metadata. See lvmcache(7) for more information.

--cachesize Size[m|UNIT]
The size of cache to use.

--cachevol LV
The name of a cache volume.

-c|--chunksize Size[k|UNIT]
The size of chunks in a snapshot, cache pool or thin pool. For snapshots, the value must be a power of 2 between 4KiB and 512KiB and the default value is 4. For a cache pool the value must be between 32KiB and 1GiB and the default value is 64. For a thin pool the value must be between 64KiB and 1GiB and the default value starts with 64 and scales up to fit the pool metadata size within 128MiB, if the pool metadata size is not specified. The value must be a multiple of 64KiB. See lvmthin(7) and lvmcache(7) for more information.

--commandprofile String
The command profile to use for command configuration. See lvm.conf(5) for more information about profiles.

--compression y|n
Controls whether compression is enabled or disable for VDO volume. See lvmvdo(7) for more information about VDO usage.

--config String
Config settings for the command. These override lvm.conf(5) settings. The String arg uses the same format as lvm.conf(5), or may use section/field syntax. See lvm.conf(5) for more information about config.

-C|--contiguous y|n
Sets or resets the contiguous allocation policy for LVs. Default is no contiguous allocation based on a next free principle. It is only possible to change a non-contiguous allocation policy to contiguous if all of the allocated physical extents in the LV are already contiguous.

-d|--debug ...
Set debug level. Repeat from 1 to 6 times to increase the detail of messages sent to the log file and/or syslog (if configured).

--deduplication y|n
Controls whether deduplication is enabled or disable for VDO volume. See lvmvdo(7) for more information about VDO usage.

--devices PV
Restricts the devices that are visible and accessible to the command. Devices not listed will appear to be missing. This option can be repeated, or accepts a comma separated list of devices. This overrides the devices file.

--devicesfile String
A file listing devices that LVM should use. The file must exist in /etc/lvm/devices/ and is managed with the lvmdevices(8) command. This overrides the lvm.conf(5) devices/devicesfile and devices/use_devicesfile settings.

--discards passdown|nopassdown|ignore
Specifies how the device-mapper thin pool layer in the kernel should handle discards. ignore causes the thin pool to ignore discards. nopassdown causes the thin pool to process discards itself to allow reuse of unneeded extents in the thin pool. passdown causes the thin pool to process discards itself (like nopassdown) and pass the discards to the underlying device. See lvmthin(7) for more information.

--driverloaded y|n
If set to no, the command will not attempt to use device-mapper. For testing and debugging.

--errorwhenfull y|n
Specifies thin pool behavior when data space is exhausted. When yes, device-mapper will immediately return an error when a thin pool is full and an I/O request requires space. When no, device-mapper will queue these I/O requests for a period of time to allow the thin pool to be extended. Errors are returned if no space is available after the timeout. (Also see dm-thin-pool kernel module option no_space_timeout.) See lvmthin(7) for more information.

-l|--extents Number[PERCENT]
Specifies the size of the new LV in logical extents. The --size and --extents options are alternate methods of specifying size. The total number of physical extents used will be greater when redundant data is needed for RAID levels. An alternate syntax allows the size to be determined indirectly as a percentage of the size of a related VG, LV, or set of PVs. The suffix %VG denotes the total size of the VG, the suffix %FREE the remaining free space in the VG, and the suffix %PVS the free space in the specified PVs. For a snapshot, the size can be expressed as a percentage of the total size of the origin LV with the suffix %ORIGIN (100%ORIGIN provides space for the whole origin). When expressed as a percentage, the size defines an upper limit for the number of logical extents in the new LV. The precise number of logical extents in the new LV is not determined until the command has completed.

-h|--help
Display help text.

-K|--ignoreactivationskip
Ignore the "activation skip" LV flag during activation to allow LVs with the flag set to be activated.

--ignoremonitoring
Do not interact with dmeventd unless --monitor is specified. Do not use this if dmeventd is already monitoring a device.

--journal String
Record information in the systemd journal. This information is in addition to information enabled by the lvm.conf log/journal setting. command: record information about the command. output: record the default command output. debug: record full command debugging.

--lockopt String
Used to pass options for special cases to lvmlockd. See lvmlockd(8) for more information.

--longhelp
Display long help text.

-j|--major Number
Sets the major number of an LV block device.

--[raid]maxrecoveryrate Size[k|UNIT]
Sets the maximum recovery rate for a RAID LV. The rate value is an amount of data per second for each device in the array. Setting the rate to 0 means it will be unbounded. See lvmraid(7) for more information.

--metadataprofile String
The metadata profile to use for command configuration. See lvm.conf(5) for more information about profiles.

--minor Number
Sets the minor number of an LV block device.

--[raid]minrecoveryrate Size[k|UNIT]
Sets the minimum recovery rate for a RAID LV. The rate value is an amount of data per second for each device in the array. Setting the rate to 0 means it will be unbounded. See lvmraid(7) for more information.

--mirrorlog core|disk
Specifies the type of mirror log for LVs with the "mirror" type (does not apply to the "raid1" type.) disk is a persistent log and requires a small amount of storage space, usually on a separate device from the data being mirrored. core is not persistent; the log is kept only in memory. In this case, the mirror must be synchronized (by copying LV data from the first device to others) each time the LV is activated, e.g. after reboot. mirrored is a persistent log that is itself mirrored, but should be avoided. Instead, use the raid1 type for log redundancy.

-m|--mirrors Number
Specifies the number of mirror images in addition to the original LV image, e.g. --mirrors 1 means there are two images of the data, the original and one mirror image. Optional positional PV args on the command line can specify the devices the images should be placed on. There are two mirroring implementations: "raid1" and "mirror". These are the names of the corresponding LV types, or "segment types". Use the --type option to specify which to use (raid1 is default, and mirror is legacy) Use lvm.conf(5) global/mirror_segtype_default and global/raid10_segtype_default to configure the default types. See the --nosync option for avoiding initial image synchronization. See lvmraid(7) for more information.

--monitor y|n
Start (yes) or stop (no) monitoring an LV with dmeventd. dmeventd monitors kernel events for an LV, and performs automated maintenance for the LV in reponse to specific events. See dmeventd(8) for more information.

-n|--name String
Specifies the name of a new LV. When unspecified, a default name of "lvol#" is generated, where # is a number generated by LVM.

--nohints
Do not use the hints file to locate devices for PVs. A command may read more devices to find PVs when hints are not used. The command will still perform standard hint file invalidation where appropriate.

--nolocking
Disable locking.

--nosync
Causes the creation of mirror, raid1, raid4, raid5 and raid10 to skip the initial synchronization. In case of mirror, raid1 and raid10, any data written afterwards will be mirrored, but the original contents will not be copied. In case of raid4 and raid5, no parity blocks will be written, though any data written afterwards will cause parity blocks to be stored. This is useful for skipping a potentially long and resource intensive initial sync of an empty mirror/raid1/raid4/raid5 and raid10 LV. This option is not valid for raid6, because raid6 relies on proper parity (P and Q Syndromes) being created during initial synchronization in order to reconstruct proper user date in case of device failures. raid0 and raid0_meta do not provide any data copies or parity support and thus do not support initial synchronization.

--noudevsync
Disables udev synchronisation. The process will not wait for notification from udev. It will continue irrespective of any possible udev processing in the background. Only use this if udev is not running or has rules that ignore the devices LVM creates.

-p|--permission rw|r
Set access permission to read only r or read and write rw.

-M|--persistent y|n
When yes, makes the specified minor number persistent.

--poolmetadatasize Size[m|UNIT]
Specifies the size of the new pool metadata LV.

--poolmetadataspare y|n
Enable or disable the automatic creation and management of a spare pool metadata LV in the VG. A spare metadata LV is reserved space that can be used when repairing a pool.

--profile String
An alias for --commandprofile or --metadataprofile, depending on the command.

-q|--quiet ...
Suppress output and log messages. Overrides --debug and --verbose. Repeat once to also suppress any prompts with answer 'no'.

--raidintegrity y|n
Enable or disable data integrity checksums for raid images.

--raidintegrityblocksize Number
The block size to use for dm-integrity on raid images. The integrity block size should usually match the device logical block size, or the file system block size. It may be less than the file system block size, but not less than the device logical block size. Possible values: 512, 1024, 2048, 4096.

--raidintegritymode String
Use a journal (default) or bitmap for keeping integrity checksums consistent in case of a crash. The bitmap areas are recalculated after a crash, so corruption in those areas would not be detected. A journal does not have this problem. The journal mode doubles writes to storage, but can improve performance for scattered writes packed into a single journal write. bitmap mode can in theory achieve full write throughput of the device, but would not benefit from the potential scattered write optimization.

-r|--readahead auto|none|Number
Sets read ahead sector count of an LV. auto is the default which allows the kernel to choose a suitable value automatically. none is equivalent to zero.

-R|--regionsize Size[m|UNIT]
Size of each raid or mirror synchronization region. lvm.conf(5) activation/raid_region_size can be used to configure a default.

--reportformat basic|json
Overrides current output format for reports which is defined globally by the report/output_format setting in lvm.conf(5). basic is the original format with columns and rows. If there is more than one report per command, each report is prefixed with the report name for identification. json produces report output in JSON format. See lvmreport(7) for more information.

-k|--setactivationskip y|n
Persistently sets (yes) or clears (no) the "activation skip" flag on an LV. An LV with this flag set is not activated unless the --ignoreactivationskip option is used by the activation command. This flag is set by default on new thin snapshot LVs. The flag is not applied to deactivation. The current value of the flag is indicated in the lvs lv_attr bits.

--setautoactivation y|n
Set the autoactivation property on a VG or LV. Display the property with vgs or lvs "-o autoactivation". When the autoactivation property is disabled, the VG or LV will not be activated by a command doing autoactivation (vgchange, lvchange, or pvscan using -aay.) If autoactivation is disabled on a VG, no LVs will be autoactivated in that VG, and the LV autoactivation property has no effect. If autoactivation is enabled on a VG, autoactivation can be disabled for individual LVs.

-L|--size Size[m|UNIT]
Specifies the size of the new LV. The --size and --extents options are alternate methods of specifying size. The total number of physical extents used will be greater when redundant data is needed for RAID levels.

-s|--snapshot
Create a snapshot. Snapshots provide a "frozen image" of an origin LV. The snapshot LV can be used, e.g. for backups, while the origin LV continues to be used. This option can create a COW (copy on write) snapshot, or a thin snapshot (in a thin pool.) Thin snapshots are created when the origin is a thin LV and the size option is NOT specified. Thin snapshots share the same blocks in the thin pool, and do not allocate new space from the VG. Thin snapshots are created with the "activation skip" flag, see --setactivationskip. A thin snapshot of a non-thin "external origin" LV is created when a thin pool is specified. Unprovisioned blocks in the thin snapshot LV are read from the external origin LV. The external origin LV must be read-only. See lvmthin(7) for more information about LVM thin provisioning. COW snapshots are created when a size is specified. The size is allocated from space in the VG, and is the amount of space that can be used for saving COW blocks as writes occur to the origin or snapshot. The size chosen should depend upon the amount of writes that are expected; often 20% of the origin LV is enough. If COW space runs low, it can be extended with lvextend (shrinking is also allowed with lvreduce.) A small amount of the COW snapshot LV size is used to track COW block locations, so the full size is not available for COW data blocks. Use lvs to check how much space is used, and see --monitor to to automatically extend the size to avoid running out of space.

-i|--stripes Number
Specifies the number of stripes in a striped LV. This is the number of PVs (devices) that a striped LV is spread across. Data that appears sequential in the LV is spread across multiple devices in units of the stripe size (see --stripesize). This does not change existing allocated space, but only applies to space being allocated by the command. When creating a RAID 4/5/6 LV, this number does not include the extra devices that are required for parity. The largest number depends on the RAID type (raid0: 64, raid10: 32, raid4/5: 63, raid6: 62), and when unspecified, the default depends on the RAID type (raid0: 2, raid10: 2, raid4/5: 3, raid6: 5.) To stripe a new raid LV across all PVs by default, see lvm.conf(5) allocation/raid_stripe_all_devices.

-I|--stripesize Size[k|UNIT]
The amount of data that is written to one device before moving to the next in a striped LV.

-t|--test
Run in test mode. Commands will not update metadata. This is implemented by disabling all metadata writing but nevertheless returning success to the calling function. This may lead to unusual error messages in multi-stage operations if a tool relies on reading back metadata it believes has changed but hasn't.

-T|--thin
Specifies the command is handling a thin LV or thin pool. See --type thin, --type thin-pool, and --virtualsize. See lvmthin(7) for more information about LVM thin provisioning.

--thinpool LV
The name of a thin pool LV.

--type linear|striped|snapshot|raid|mirror|thin|thin-pool|vdo|vdo-pool|cache|cache-pool|writecache
The LV type, also known as "segment type" or "segtype". See usage descriptions for the specific ways to use these types. For more information about redundancy and performance (raid<N>, mirror, striped, linear) see lvmraid(7). For thin provisioning (thin, thin-pool) see lvmthin(7). For performance caching (cache, cache-pool) see lvmcache(7). For copy-on-write snapshots (snapshot) see usage definitions. For VDO (vdo) see lvmvdo(7). Several commands omit an explicit type option because the type is inferred from other options or shortcuts (e.g. --stripes, --mirrors, --snapshot, --virtualsize, --thin, --cache, --vdo). Use inferred types with care because it can lead to unexpected results.

--vdo
Specifies the command is handling VDO LV. See --type vdo. See lvmvdo(7) for more information about VDO usage.

--vdopool LV
The name of a VDO pool LV. See lvmvdo(7) for more information about VDO usage.

--vdosettings String
Specifies tunable VDO options for VDO LVs. Use the form 'option=value' or 'option1=value option2=value', or repeat --vdosettings for each option being set. These settings override the default VDO behaviors. To remove vdosettings and revert to the default VDO behaviors, use --vdosettings 'default'. See lvmvdo(7) for more information.

-v|--verbose ...
Set verbose level. Repeat from 1 to 4 times to increase the detail of messages sent to stdout and stderr.

--version
Display version information.

-V|--virtualsize Size[m|UNIT]
The virtual size of a new thin LV. See lvmthin(7) for more information about LVM thin provisioning. Using virtual size (-V) and actual size (-L) together creates a sparse LV. lvm.conf(5) global/sparse_segtype_default determines the default segment type used to create a sparse LV. Anything written to a sparse LV will be returned when reading from it. Reading from other areas of the LV will return blocks of zeros. When using a snapshot to create a sparse LV, a hidden virtual device is created using the zero target, and the LV has the suffix _vorigin. Snapshots are less efficient than thin provisioning when creating large sparse LVs (GiB).

-W|--wipesignatures y|n
Controls detection and subsequent wiping of signatures on new LVs. There is a prompt for each signature detected to confirm its wiping (unless --yes is used to override confirmations.) When not specified, signatures are wiped whenever zeroing is done (see --zero). This behaviour can be configured with lvm.conf(5) allocation/wipe_signatures_when_zeroing_new_lvs. If blkid wiping is used (lvm.conf(5) allocation/use_blkid_wiping) and LVM is compiled with blkid wiping support, then the blkid(8) library is used to detect the signatures (use blkid -k to list the signatures that are recognized). Otherwise, native LVM code is used to detect signatures (only MD RAID, swap and LUKS signatures are detected in this case.) The LV is not wiped if the read only flag is set.

-y|--yes
Do not prompt for confirmation interactively but always assume the answer yes. Use with extreme caution. (For automatic no, see -qq.)

-Z|--zero y|n
Controls zeroing of the first 4KiB of data in the new LV. Default is y. Snapshot COW volumes are always zeroed. For thin pools, this controls zeroing of provisioned blocks. LV is not zeroed if the read only flag is set. Warning: trying to mount an unzeroed LV can cause the system to hang.

VARIABLES¶

VG

Volume Group name. See lvm(8) for valid names. For lvcreate, the required VG positional arg may be omitted when the VG name is included in another option, e.g. --name VG/LV.

LV

Logical Volume name. See lvm(8) for valid names. An LV positional arg generally includes the VG name and LV name, e.g. VG/LV. LV1 indicates the LV must have a specific type, where the accepted LV types are listed. (raid represents raid<N> type).

PV

Physical Volume name, a device path under /dev. For commands managing physical extents, a PV positional arg generally accepts a suffix indicating a range (or multiple ranges) of physical extents (PEs). When the first PE is omitted, it defaults to the start of the device, and when the last PE is omitted it defaults to end. Start and end range (inclusive): PV[:PE-PE]... Start and length range (counting from 0): PV[:PE+PE]...

String

See the option description for information about the string content.

Size[UNIT]

Size is an input number that accepts an optional unit. Input units are always treated as base two values, regardless of capitalization, e.g. 'k' and 'K' both refer to 1024. The default input unit is specified by letter, followed by |UNIT. UNIT represents other possible input units: b|B is bytes, s|S is sectors of 512 bytes, k|K is KiB, m|M is MiB, g|G is GiB, t|T is TiB, p|P is PiB, e|E is EiB. (This should not be confused with the output control --units, where capital letters mean multiple of 1000.)

ENVIRONMENT VARIABLES¶

See lvm(8) for information about environment variables used by lvm. For example, LVM_VG_NAME can generally be substituted for a required VG parameter.

ADVANCED USAGE¶

Alternate command forms, advanced command usage, and listing of all valid syntax for completeness.

Create an LV that returns errors when used.

lvcreate --type error -L|--size Size[m|UNIT] VG

—

Create an LV that returns zeros when read.

lvcreate --type zero -L|--size Size[m|UNIT] VG

—

Create a linear LV.

lvcreate --type linear -L|--size Size[m|UNIT] VG

—

Create a striped LV (also see lvcreate --stripes).

lvcreate --type striped -L|--size Size[m|UNIT] VG

—

Create a mirror LV (also see --type raid1).

lvcreate --type mirror -L|--size Size[m|UNIT] VG

—

Create a COW snapshot LV of an origin LV
(also see --snapshot).

lvcreate --type snapshot -L|--size Size[m|UNIT] LV

—

Create a sparse COW snapshot LV of a virtual origin LV
(also see --snapshot).

lvcreate --type snapshot -L|--size Size[m|UNIT]

—

Create a thin pool.

lvcreate -T|--thin -L|--size Size[m|UNIT] VG

—

Create a thin pool named in --thinpool.

lvcreate -L|--size Size[m|UNIT] --thinpool LV_new VG

—

Create a cache pool named by the --cachepool arg
(variant, uses --cachepool in place of --name).

lvcreate --type cache-pool -L|--size Size[m|UNIT]

—

Create a thin LV in a thin pool.

lvcreate --type thin -V|--virtualsize Size[m|UNIT]

—

Create a thin LV in a thin pool named in the first arg
(variant, also see --thinpool for naming pool).

lvcreate --type thin -V|--virtualsize Size[m|UNIT] LV1

—

Create a thin LV in the thin pool named in the first arg
(also see --thinpool for naming pool.)

lvcreate -V|--virtualsize Size[m|UNIT] LV1

—

Create a thin LV that is a snapshot of an existing thin LV.

lvcreate --type thin LV1

—

Create a thin LV that is a snapshot of an existing thin LV.

lvcreate -T|--thin LV1

—

Create a thin LV that is a snapshot of an external origin LV.

lvcreate -s|--snapshot --thinpool LV LV

—

Create a VDO LV with VDO pool.

lvcreate --vdo -L|--size Size[m|UNIT] VG

—

Create a VDO LV with VDO pool.

lvcreate --vdopool LV_new -L|--size Size[m|UNIT] VG

—

Create a thin LV, first creating a thin pool for it,
where the new thin pool is named by the --thinpool arg.

lvcreate --type thin -V|--virtualsize Size[m|UNIT]

—

Create a thin LV, first creating a thin pool for it,
where the new thin pool is named by --thinpool.

lvcreate -V|--virtualsize Size[m|UNIT] -L|--size Size[m|UNIT]

—

Create a thin LV, first creating a thin pool for it,
where the new thin pool is named in the first arg,
or the new thin pool name is generated when the first
arg is a VG name.

lvcreate --type thin -V|--virtualsize Size[m|UNIT]

—

Create a thin LV, first creating a thin pool for it,
where the new thin pool is named in the first arg,
or the new thin pool name is generated when the first
arg is a VG name.

lvcreate -T|--thin -V|--virtualsize Size[m|UNIT]

—

Create a thin LV, first creating a thin pool for it.
Create a sparse snapshot of a virtual origin LV
Chooses type thin or snapshot according to
config setting sparse_segtype_default.

lvcreate -L|--size Size[m|UNIT] -V|--virtualsize Size[m|UNIT] VG

—

Create a new LV, then attach the specified cachepool
which converts the new LV to type cache.

lvcreate -L|--size Size[m|UNIT] --cachepool LV VG

—

Create a new LV, then attach the specified cachepool
which converts the new LV to type cache.
(variant, also use --cachepool).

lvcreate --type cache -L|--size Size[m|UNIT] LV1

—

When the LV arg is a cachepool, then create a new LV and
attach the cachepool arg to it.
(variant, use --type cache and --cachepool.)
When the LV arg is not a cachepool, then create a new cachepool
and attach it to the LV arg (alternative, use lvconvert.)

lvcreate -H|--cache -L|--size Size[m|UNIT] LV

—

EXAMPLES¶

Create a striped LV with 3 stripes, a stripe size of 8KiB and a size of 100MiB. The LV name is chosen by lvcreate.
lvcreate -i 3 -I 8 -L 100m vg00

Create a raid1 LV with two images, and a useable size of 500 MiB. This operation requires two devices, one for each mirror image. RAID metadata (superblock and bitmap) is also included on the two devices.
lvcreate --type raid1 -m1 -L 500m -n mylv vg00

Create a mirror LV with two images, and a useable size of 500 MiB. This operation requires three devices: two for mirror images and one for a disk log.
lvcreate --type mirror -m1 -L 500m -n mylv vg00

Create a mirror LV with 2 images, and a useable size of 500 MiB. This operation requires 2 devices because the log is in memory.
lvcreate --type mirror -m1 --mirrorlog core -L 500m -n mylv vg00

Create a copy-on-write snapshot of an LV:
lvcreate --snapshot --size 100m --name mysnap vg00/mylv

Create a copy-on-write snapshot with a size sufficient for overwriting 20% of the size of the original LV.
lvcreate -s -l 20%ORIGIN -n mysnap vg00/mylv

Create a sparse LV with 1TiB of virtual space, and actual space just under 100MiB.
lvcreate --snapshot --virtualsize 1t --size 100m --name mylv vg00

Create a linear LV with a usable size of 64MiB on specific physical extents.
lvcreate -L 64m -n mylv vg00 /dev/sda:0-7 /dev/sdb:0-7

Create a RAID5 LV with a usable size of 5GiB, 3 stripes, a stripe size of 64KiB, using a total of 4 devices (including one for parity).
lvcreate --type raid5 -L 5G -i 3 -I 64 -n mylv vg00

Create a RAID5 LV using all of the free space in the VG and spanning all the PVs in the VG (note that the command will fail if there are more than 8 PVs in the VG, in which case -i 7 must be used to get to the current maximum of 8 devices including parity for RaidLVs).
lvcreate --config allocation/raid_stripe_all_devices=1

Create RAID10 LV with a usable size of 5GiB, using 2 stripes, each on a two-image mirror. (Note that the -i and -m arguments behave differently: -i specifies the total number of stripes, but -m specifies the number of images in addition to the first image).
lvcreate --type raid10 -L 5G -i 2 -m 1 -n mylv vg00

Create a 1TiB thin LV mythin, with 256GiB thinpool tpool0 in vg00.
lvcreate -T -V 1T --size 256G --name mythin vg00/tpool0

Create a 1TiB thin LV, first creating a new thin pool for it, where the thin pool has 100MiB of space, uses 2 stripes, has a 64KiB stripe size, and 256KiB chunk size.
lvcreate --type thin --name mylv --thinpool mypool

Create a thin snapshot of a thin LV (the size option must not be used, otherwise a copy-on-write snapshot would be created).
lvcreate --snapshot --name mysnap vg00/thinvol

Create a thin snapshot of the read-only inactive LV named "origin" which becomes an external origin for the thin snapshot LV.
lvcreate --snapshot --name mysnap --thinpool mypool vg00/origin

Create a cache pool from a fast physical device. The cache pool can then be used to cache an LV.
lvcreate --type cache-pool -L 1G -n my_cpool vg00 /dev/fast1

Create a cache LV, first creating a new origin LV on a slow physical device, then combining the new origin LV with an existing cache pool.
lvcreate --type cache --cachepool my_cpool

Create a VDO LV vdo0 with VDOPoolLV size of 10GiB and name vpool1.
lvcreate --vdo --size 10G --name vdo0 vg00/vpool1

SEE ALSO¶

lvm(8), lvm.conf(5), lvmconfig(8), lvmdevices(8),

pvchange(8), pvck(8), pvcreate(8), pvdisplay(8), pvmove(8), pvremove(8), pvresize(8), pvs(8), pvscan(8),

vgcfgbackup(8), vgcfgrestore(8), vgchange(8), vgck(8), vgcreate(8), vgconvert(8), vgdisplay(8), vgexport(8), vgextend(8), vgimport(8), vgimportclone(8), vgimportdevices(8), vgmerge(8), vgmknodes(8), vgreduce(8), vgremove(8), vgrename(8), vgs(8), vgscan(8), vgsplit(8),

lvcreate(8), lvchange(8), lvconvert(8), lvdisplay(8), lvextend(8), lvreduce(8), lvremove(8), lvrename(8), lvresize(8), lvs(8), lvscan(8),

lvm-fullreport(8), lvm-lvpoll(8), lvm2-activation-generator(8), blkdeactivate(8), lvmdump(8),

dmeventd(8), lvmpolld(8), lvmlockd(8), lvmlockctl(8), cmirrord(8), lvmdbusd(8), fsadm(8),

lvmsystemid(7), lvmreport(7), lvmraid(7), lvmthin(7), lvmcache(7)