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



NAME
       lvreduce — reduce the size of a logical volume

SYNOPSIS
       lvreduce  [-A|--autobackup  {y|n}] [--commandprofile ProfileName] [-d|--debug] [-h|--help] [-t|--test] [-v|--verbose] [--version]
       [-f|--force]  [--noudevsync]   {-l|--extents   [-]LogicalExtentsNumber[%{VG|LV|FREE|ORIGIN}]   |   [-L|--size   [-]LogicalVolume‐
       Size[bBsSkKmMgGtTpPeE]} [-n|--nofsck] [-r|--resizefs] LogicalVolume{Name|Path}

DESCRIPTION
       lvreduce  allows  you  to reduce the size of a logical volume.  Be careful when reducing a logical volume's size, because data in
       the reduced part is lost!!!
       You should therefore ensure that any filesystem on the volume is resized before running lvreduce so that the extents that are  to
       be removed are not in use.
       Shrinking snapshot logical volumes (see lvcreate(8) for information to create snapshots) is supported as well.  But to change the
       number of copies in a mirrored logical volume use lvconvert(8).
       Sizes will be rounded if necessary - for example, the volume size must be an exact number of extents and the size  of  a  striped
       segment must be a multiple of the number of stripes.

OPTIONS
       See lvm(8) for common options.

       -f, --force
              Force size reduction without prompting even when it may cause data loss.

       -l, --extents [-]LogicalExtentsNumber[%{VG|LV|FREE|ORIGIN}]
              Reduce  or set the logical volume size in units of logical extents.  With the - sign the value will be subtracted from the
              logical volume's actual size and without it the value will be taken as an absolute size.  The  total  number  of  physical
              extents  freed  will  be  greater than this logical value if, for example, the volume is mirrored.  The number can also be
              expressed as a percentage of the total space in the Volume Group with the suffix %VG, relative to the existing size of the
              Logical Volume with the suffix %LV, as a percentage of the remaining free space in the Volume Group with the suffix %FREE,
              or (for a snapshot) as a percentage of the total space in the Origin Logical Volume with the suffix %ORIGIN.  The  result‐
              ing  value for the subtraction is rounded downward, for the absolute size it is rounded upward.  N.B. In a future release,
              when expressed as a percentage with VG or FREE, the number will be treated as an  approximate  total  number  of  physical
              extents  to be freed (including extents used by any mirrors, for example).  The code may currently release more space than
              you might otherwise expect.

       -L, --size [-]LogicalVolumeSize[bBsSkKmMgGtTpPeE]
              Reduce or set the logical volume size in units of megabytes.  A size suffix of k for kilobyte, m for megabyte, g for giga‐
              bytes,  t for terabytes, p for petabytes or e for exabytes is optional.  With the - sign the value will be subtracted from
              the logical volume's actual size and without it it will be taken as an absolute size.

       -n, --nofsck
              Do not perform fsck before resizing filesystem when filesystem requires it. You may need to use --force  to  proceed  with
              this option.

       --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.

       -r, --resizefs
              Resize underlying filesystem together with the logical volume using fsadm(8).

Examples
       Reduce the size of logical volume lvol1 in volume group vg00 by 3 logical extents:

       lvreduce -l -3 vg00/lvol1

SEE ALSO
       fsadm(8), lvchange(8), lvconvert(8), lvcreate(8), lvextend(8), lvm(8), lvresize(8), vgreduce(8)



Sistina Software UK                                LVM TOOLS 2.02.111(2) (2014-09-01)                                        LVREDUCE(8)