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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	 [-]LogicalExtentsNum-
       ber[%{VG|LV|FREE|ORIGIN}] |  -L|--size  [-]LogicalVolumeSize[bBsSkKmMg-
       GtTpPeE]}  [-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 example,
	      the volume is mirrored.  The number can also be expressed	 as  a
	      percentage  of the total space in the Volume Group with the suf-
	      fix %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 resulting value for	 the  subtrac-
	      tion  is	rounded	 downward, for the absolute size it is rounded
	      upward.  N.B. In a future release, when expressed as a  percent-
	      age  with	 VG or FREE, the number will be treated as an approxi-
	      mate total number of physical extents  to	 be  freed  (including
	      extents  used  by	 any mirrors, for example).  The code may cur-
	      rently 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 abso-
	      lute 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 logi-
       cal 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 UKLVM TOOLS 2.02.166(2)-RHEL7 (2016-11-16)	   LVREDUCE(8)