LVCREATE(8)						      System Manager's Manual						       LVCREATE(8)

NAME

       lvcreate - create a logical volume in an existing volume group

SYNOPSIS

       lvcreate  [-A|--autobackup  {y|n}]  [-C|--contiguous {y|n}] [-d|--debug] [-h|--help] [-i|--stripes StripesI] [-I|--stripesize StripeSizeI]]
       {-l|--extents  LogicalExtentsNumber|   -L|--size   LogicalVolumeSize[kKmMgGtT]}	 [-n|--name   LogicalVolumeName]   [-p|--permission{r|rw}]
       [-r|--readahead ReadAheadSectors] [-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 [PhysicalVolumePath...]

DESCRIPTION

       lvcreate creates a new logical volume in a volume group ( see vgcreate(8), vgchange(8) ) by allocating logical extents from the free physi-
       cal  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), e2fsadm(8) ).
       The second form supports the creation of snapshot logical volumes which keep the contents of the original logical volume  for  backup  pur-
       poses.

   OPTIONS
       -A, --autobackup {y|n}
	      Controls automatic backup of VG metadata after the change ( see vgcfgbackup(8) ).
	      Default is yes.

       -c, --chunksize ChunkSize
	      Power of 2 chunk size for the snapshot logical volume between 4k and 1024k.

       -C, --contiguous y/n
	      Sets  or resets the contiguous allocation policy for logical volumes. Default is no contiguous allocation based on a next free prin-
	      ciple.

       -d, --debug
	      Enables additional debugging output (if compiled with DEBUG).

       -h, --help
	      Print a usage message on standard output and exit successfully.

       -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 logical 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.

       -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.

       -s, --snapshot
	      Create  a snapshot logical volume (or snapshot) for an existing, so called original logical volume (or origin).  Snapshots provide a
	      'frozen image' of the contents of the origin while the origin can still be updated. They enable consistent backups and online recov-
	      ery  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.

       -v, --verbose
	      Gives verbose information about lvcreate's activities.

       -Z, --zero y/n
	      Controls zeroing of the first KB of data in the new logical volume.
	      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 volume with 3 stripes, a stripesize of 8KB and a size of 100MB in the
       volume group named vg00. The logical volume name will be chosen by lvcreate.

       "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 is
       updated.

DIAGNOSTICS

       lvcreate returns an exit code of 0 for success or > 0 for error:

       1  invalid volume group name
       2  error checking existence of volume group
       3  volume group inactive
       4  invalid logical volume name
       5  error getting status of logical volume
       6  error checking existence of logical volume
       7  invalid physical volume name
       8  invalid number of physical volumes
       9  invalid number of stripes
       10 invalid stripe size
       11 error getting status of volume group
       12 invalid logical volume size
       13 invalid number of free physical extents
       14 more stripes than physical volumes requested
       15 error reading VGDA
       16 requested physical volume not in volume group
       17 error reading physical volume
       18 maximum number of logical volumes exceeded
       19 not enoungh space available to create logical volume
       20 error setting up VGDA for logical volume creation
       21 error creating VGDA for logical volume in kernel
       22 error writing VGDA to physical volume(s)
       23 error creating device special for logical volume
       24 error opening logical volume
       25 error writing to logical volume
       26 invalid read ahead sector count
       27 no free logical volume manager block specials available
       28 invalid snapshot logical volume name
       29 error setting up snapshot copy on write exception table
       30 error initializing snapshot copy on write exception table on disk
       31 error getting status of logical volume from kernel
       32 snapshot already exists

       95 driver/module not in kernel
       96 invalid I/O protocol version
       97 error locking logical volume manager
       98 invalid lvmtab (run vgscan(8))
       99 invalid command line

ENVIRONMENT VARIABLES

       LVM_AUTOBACKUP
	      If this variable is set to "no" then the automatic backup of VG metadata is turned off.

       LVM_VG_MAX_BACKUPS
	      This  variable  determines  the  backup  history	depth  of kept VGDA copy files in /etc/lvmconf. It can be set to a positive number
	      between 0 and 999.  The higher this number is, the more changes you can restore using vgcfgrestore(8).

       LVM_VG_NAME
	      The default Volume Group Name to use. Setting this variable enables you to enter just the Logical Volume Name rather than  its  com-
	      plete path.

See also
       lvm(8), vgcreate(8), lvremove(8), lvrename(8),
       lvextend(8), lvreduce(8), lvdisplay(8), lvscan(8),
       lvmsadc(8), lvmsar(8)

AUTHOR

       Heinz Mauelshagen <Linux-LVM@Sistina.com>

Heinz Mauelshagen						     LVM TOOLS							       LVCREATE(8)