LVCREATE(8)LVCREATE(8)NAMElvcreate - create a logical volume in an existing volume group
SYNOPSISlvcreate [--addtag Tag] [--alloc AllocationPolicy] [-A/--autobackup
y/n] [-C/--contiguous y/n] [-d/--debug] [-h/-?/--help] [-i/--stripes
Stripes [-I/--stripesize StripeSize]] {-l/--extents LogicalExtentsNum‐
ber |
-L/--size LogicalVolumeSize[kKmMgGtT]} [-M/--persistent y/n] [--minor
minor] [-n/--name LogicalVolumeName] [-p/--permission r/rw]
[-r/--readahead ReadAheadSectors] [-t/--test] [-v/--verbose] [-Z/--zero
y/n] VolumeGroupName [PhysicalVolumePath...]
lvcreate {-l/--extents LogicalExtentsNumber |
-L/--size LogicalVolumeSize[kKmMgGtT]} [-c/--chunksize ChunkSize]
-s/--snapshot -n/--name SnapshotLogicalVolumeName OriginalLogicalVol‐
umePath
DESCRIPTIONlvcreate creates a new logical volume in a volume group ( see vgcre‐
ate(8), vgchange(8) ) by allocating logical extents from the free phys‐
ical extent pool of that volume group. If there are not enough free
physical extents then the volume group can be extended ( see vgex‐
tend(8) ) with other physical volumes or by reducing existing logical
volumes of this volume group in size ( see lvreduce(8) ).
The second form supports the creation of snapshot logical volumes which
keep the contents of the original logical volume for backup purposes.
OPTIONS
See lvm for common options.
-c, --chunksize ChunkSize
Power of 2 chunk size for the snapshot logical volume between 4k
and 512k.
-C, --contiguous y/n
Sets or resets the contiguous allocation policy for logical vol‐
umes. Default is no contiguous allocation based on a next free
principle.
-i, --stripes Stripes
Gives the number of stripes. This is equal to the number of
physical volumes to scatter the logical volume.
-I, --stripesize StripeSize
Gives the number of kilobytes for the granularity of the
stripes.
StripeSize must be 2^n (n = 2 to 9)
-l, --extents LogicalExtentsNumber
Gives the number of logical extents to allocate for the new log‐
ical volume.
-L, --size LogicalVolumeSize[kKmMgGtT]
Gives the size to allocate for the new logical volume. A size
suffix of K for kilobytes, M for megabytes, G for gigabytes or T
for terabytes is optional.
Default unit is megabytes.
--minor minor
Set the minor number.
-M, --persistent y/n
Set to y to make the minor number specified persistent.
-n, --name LogicalVolumeName
The name for the new logical volume.
Without this option a default names of "lvol#" will be generated
where # is the LVM internal number of the logical volume.
-p, --permission r/w
Set access permissions to read only or read and write.
Default is read and write.
-r, --readahead ReadAheadSectors
Set read ahead sector count of this logical volume to a value
between 2 and 120. Ignored by device-mapper.
-s, --snapshot
Create a snapshot logical volume (or snapshot) for an existing,
so called original logical volume (or origin). Snapshots pro‐
vide a 'frozen image' of the contents of the origin while the
origin can still be updated. They enable consistent backups and
online recovery of removed/overwritten data/files. The snapshot
does not need the same amount of storage the origin has. In a
typical scenario, 15-20% might be enough. In case the snapshot
runs out of storage, use lvextend(8) to grow it. Shrinking a
snapshot is supported by lvreduce(8) as well. Run lvdisplay(8)
on the snapshot in order to check how much data is allocated to
it.
-Z, --zero y/n
Controls zeroing of the first KB of data in the new logical vol‐
ume.
Default is yes.
Warning: trying to mount an unzeroed logical volume can cause
the system to hang.
Examples
"lvcreate -i 3 -I 8 -L 100 vg00" tries to create a striped logical vol‐
ume with 3 stripes, a stripesize of 8KB and a size of 100MB in the vol‐
ume group named vg00. The logical volume name will be chosen by lvcre‐
ate.
"lvcreate --size 100m --snapshot --name snap /dev/vg00/lvol1"
creates a snapshot logical volume named /dev/vg00/snap which has access
to the contents of the original logical volume named /dev/vg00/lvol1 at
snapshot logical volume creation time. If the original logical volume
contains a file system, you can mount the snapshot logical volume on an
arbitrary directory in order to access the contents of the filesystem
to run a backup while the original filesystem continues to get updated.
SEE ALSOlvm(8), vgcreate(8), lvremove(8), lvrename(8)lvextend(8), lvreduce(8),
lvdisplay(8), lvscan(8)Sistina Software UK LVM TOOLS LVCREATE(8)
