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

NAME

       lvreduce - reduce the size of a logical volume

SYNOPSIS

       lvreduce  [-A|--autobackup  {y|n}] [-d|--debug] [-f|--force] [-h|--help] {-l|--extents [-]LogicalExtentsNumber| -L|--size [-]LogicalVolume-
       Size[kKmMgGtT]} [-v|--verbose] LogicalVolumePath

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 the (eg) filesystem on the volume is resized running lvreduce so that the extents that are to be removed
       are not in use.	If the filesystem is ext2 then you can use the e2fsadm(8) command to both resize the filesystem  and  the  logical  volume
       together.  Shrinking snapshot logical volumes (see lvcreate(8) for information to create snapshots) is supported as well.

   OPTIONS
       -A, --autobackup y/n
	      Controls automatic backup of VG metadata after the change ( see vgcfgbackup(8) ). Default is yes.

       -d, --debug
	      Enables additional debugging output (if compiled with DEBUG).

       -f, --force
	      Force size reduction without any question.

       -h, --help
	      Print a usage message on standard output and exit successfully.

       -l, --extents [-]LogicalExtentsNumber
	      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 will be taken as an absolute size.

       -L, --size [-]LogicalVolumeSize[kKmMgGtT]
	      Reduce or set the logical volume size in units of megabyte by default.  A size suffix of k for kilobyte, m for megabyte, g for giga-
	      byte  or t for terabyte is optional.  With the - sign the value will be subtracted from the logical volume's actual size and without
	      it the will be taken as an absolute size.

       -v, --verbose
	      Gives verbose runtime information about lvreduce's activities.

Example
       "lvreduce -l -3 /dev/vg00/lvol1" reduces the size of logical volume lvol1 in volume group vg00 by 3 logical extents.

DIAGNOSTICS

       lvreduce returns an exit code of 0 for success and > 0 for error:

       1  no logical volume name on command line
       2  invalid logical volume name
       3  logical volume is not active
       4  logical volume doesn't exist
       5  error reading VGDA
       6  error getting index of logical volume
       7  new size of logical volume not smaller than old one
       8  error setting VGDA up for reduce
       9  error reducing logical volume in kernel
       10 error writing VGDA to physical volume(s)
       11 error getting index for read/write statistic transfer
       12 error getting status of logical volume from kernel
       13 error setting up copy on write exception table

       95 driver/module not in kernel
       96 invalid I/O protocol version
       97 error locking logical volume manager
       98 invalid lvmtab (run vgscan(8))
       99 invalid command line

ENVIRONMENT VARIABLES

       LVM_AUTOBACKUP
	      If this variable is set to "no" then the automatic backup of VG metadata is turned off.

       LVM_VG_MAX_BACKUPS
	      This variable determins the backup history depth of kept VGDA copy files in /etc/lvmconf. It can be set to a positive number between
	      0  and  999.  The higher this number is the more steps are you able to backup with vgcfgrestore(8) from the changes you make to your
	      volume groups.

       LVM_VG_NAME
	      The default Volume Group Name to use. Setting this variable enables you to enter just the Logical Volume Name rather than  its  com-
	      plete path.

See also
       lvm(8), lvcreate(8), lvextend(8), lvchange(8), e2fsadm(8)

AUTHOR

       Heinz Mauelshagen <Linux-LVM@Sistina.com>

Heinz Mauelshagen						     LVM TOOLS							       LVREDUCE(8)