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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|ORI‐
       GIN}]   |   -L|--size   [-]LogicalVolumeSize[bBsSkKmMgGtTpPeE]}  [-n|--nofsck]  [--reportformat  {basic|json}]
       [-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 exam‐
              ple,  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 suf‐
              fix %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).