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  [-]Logi‐
       calExtentsNumber[%{VG|LV|FREE|ORIGIN}]    |   [-L|--size   [-]LogicalVolumeSize[bBsSkKmMg‐
       GtTpPeE]} [-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  mir‐
              rored.   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 Vol‐
              ume  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 resulting 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 gigabytes, 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), vgre‐
       duce(8)



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