Provided by: lvm2_2.02.66-4ubuntu7_amd64 bug

NAME

       lvcreate - create a logical volume in an existing volume group

SYNOPSIS

       lvcreate  [--addtag Tag] [--alloc AllocationPolicy] [-A|--autobackup y|n] [-C|--contiguous
       y|n] [-d|--debug] [-h|-?|--help]  [--noudevsync]  [--ignoremonitoring]  [--monitor  {y|n}]
       [-i|--stripes        Stripes       [-I|--stripesize       StripeSize]]       {-l|--extents
       LogicalExtentsNumber[%{VG|PVS|FREE}] |
        -L|--size  LogicalVolumeSize[bBsSkKmMgGtTpPeE]}  [-M|--persistent  y|n]  [--minor  minor]
       [-m|--mirrors    Mirrors   [--nosync]   [--mirrorlog   {disk|core|mirrored}]   [--corelog]
       [-R|--regionsize  MirrorLogRegionSize]]  [-n|--name  LogicalVolumeName]   [-p|--permission
       r|rw]  [-r|--readahead  ReadAheadSectors|auto|none]  [-t|--test] [-v|--verbose] [-Z|--zero
       y|n] VolumeGroupName [PhysicalVolumePath[:PE[-PE]]...]

       lvcreate {-l|--extents LogicalExtentsNumber[%{VG|FREE|ORIGIN}] |
        -L|--size LogicalVolumeSize[bBsSkKmMgGtTpPeE]} [-c|--chunksize ChunkSize]  [--noudevsync]
       [--ignoremonitoring]     [--monitor     {y|n}]     -n|--name     SnapshotLogicalVolumeName
       {{-s|--snapshot} OriginalLogicalVolumePath | [-s|--snapshot] VolumeGroupName --virtualsize
       VirtualSize}

DESCRIPTION

       lvcreate  creates  a new logical volume in a volume group ( see vgcreate(8), vgchange(8) )
       by allocating logical extents from the free physical extent pool of that volume group.  If
       there  are  not  enough  free physical extents then the volume group can be extended ( see
       vgextend(8) ) with other physical volumes or by reducing existing logical volumes of  this
       volume  group  in  size  (  see lvreduce(8) ). If you specify one or more PhysicalVolumes,
       allocation of physical extents will be restricted to these volumes.
       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 volumes. 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) for metadata in LVM1 format.  For metadata in
              LVM2 format, the stripe size may be a larger power of 2 but  must  not  exceed  the
              physical extent size.

       -l, --extents LogicalExtentsNumber[%{VG|PVS|FREE|ORIGIN}]
              Gives  the  number  of logical extents to allocate for the new logical volume.  The
              number can also be expressed as a percentage of the total space in the Volume Group
              with  the  suffix  %VG,  as  a percentage of the remaining free space in the Volume
              Group with the suffix %FREE, as a percentage of the remaining free  space  for  the
              specified  PhysicalVolume(s)  with  the  suffix  %PVS,  or  (for  a  snapshot) as a
              percentage of the total space in the Origin Logical Volume with the suffix %ORIGIN.

       -L, --size LogicalVolumeSize[bBsSkKmMgGtTpPeE]
              Gives the size to allocate for the new logical volume.  A  size  suffix  of  K  for
              kilobytes,  M for megabytes, G for gigabytes, T for terabytes, P for petabytes or E
              for exabytes 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.

       -m, --mirrors Mirrors
              Creates a mirrored logical volume with Mirrors copies.  For example, specifying "-m
              1" would result in a mirror with two-sides; that is, a linear volume plus one copy.

              Specifying  the optional argument --nosync will cause the creation of the mirror to
              skip the initial resynchronization.  Any data written afterwards will be  mirrored,
              but  the  original  contents  will  not  be  copied.  This is useful for skipping a
              potentially long and resource intensive initial sync of an empty device.

              The optional argument --mirrorlog specifies the  type  of  log  to  be  used.   The
              default  is disk, which is persistent and requires a small amount of storage space,
              usually on a separate device from the data being mirrored.  Using  core  means  the
              mirror is regenerated by copying the data from the first device again each time the
              device is activated, for example, after every reboot.  Using "mirrored" will create
              a persistent log that is itself mirrored.

              The optional argument --corelog is equivalent to --mirrorlog core.

       -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.

       --noudevsync
              Disable udev synchronisation. The process will not wait for notification from udev.
              It  will  continue  irrespective of any possible udev processing in the background.
              You should only use this if udev is not  running  or  has  rules  that  ignore  the
              devices LVM2 creates.

       --monitor y|n
              Start  or  avoid monitoring a mirrored or snapshot logical volume with dmeventd, if
              it is installed.  If a device used by a monitored mirror reports an I/O error,  the
              failure     is     handled     according     to    mirror_image_fault_policy    and
              mirror_log_fault_policy set in lvm.conf.

       --ignoremonitoring
              Make no attempt to interact with dmeventd unless --monitor is specified.

       -p, --permission r|rw
              Set access permissions to read only or read and write.
              Default is read and write.

       -r, --readahead ReadAheadSectors|auto|none
              Set read ahead sector count  of  this  logical  volume.   For  volume  groups  with
              metadata in lvm1 format, this must be a value between 2 and 120.  The default value
              is "auto" which allows the kernel to choose a suitable value automatically.  "None"
              is equivalent to specifying zero.

       -R, --regionsize MirrorLogRegionSize
              A mirror is divided into regions of this size (in MB), and the mirror log uses this
              granularity to track which regions are in sync.

       -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  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.  Note that a small
              amount of the space you allocate to the snapshot is used to track the locations  of
              the  chunks  of  data, so you should allocate slightly more space than you actually
              need and monitor the rate at which the snapshot data is growing so  you  can  avoid
              running out of space.

       --virtualsize VirtualSize
              Create  a  sparse  device  of  the  given size (in MB by default) using a snapshot.
              Anything written to the device will be returned when reading from it.  Reading from
              other  areas  of  the  device  will  return  blocks of zeros.  It is implemented by
              creating a hidden virtual device of the requested size using the  zero  target.   A
              suffix of _vorigin is used for this device.

       -Z, --zero y|n
              Controls zeroing of the first KB of data in the new logical volume.
              Default is yes.
              Volume will not be zeroed if read only flag is set.
              Snapshot volumes are zeroed always.

              Warning: trying to mount an unzeroed logical volume can cause the system to hang.

Examples

       "lvcreate -i 3 -I 8 -L 100M 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  -m1  -L  500M vg00" tries to create a mirror logical volume with 2 sides with a
       useable size of 500 MiB.  This operation would require 3 devices  -  two  for  the  mirror
       devices and one for the disk log.

       "lvcreate  -m1 --mirrorlog core -L 500M vg00" tries to create a mirror logical volume with
       2 sides with a useable size of 500 MiB.  This operation would require 2 devices - the  log
       is "in-memory".

       "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.

       "lvcreate --virtualsize 1T --size 100M --snapshot --name sparse vg1"
       creates  a sparse device named /dev/vg1/sparse of size 1TB with space for just under 100MB
       of actual data on it.

       "lvcreate -L 64M -n lvol1 vg00 /dev/sda:0-7 /dev/sdb:0-7"
       creates a linear logical volume  "vg00/lvol1"  using  physical  extents  /dev/sda:0-7  and
       /dev/sdb:0-7 for allocation of extents.

SEE ALSO

       lvm(8),  vgcreate(8),  lvremove(8),  lvrename(8)  lvextend(8),  lvreduce(8), lvdisplay(8),
       lvscan(8)