LVREDUCE(8)



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

NAME
       lvreduce - Reduce the size of a logical volume

SYNOPSIS
       lvreduce option_args position_args
           [ option_args ]

DESCRIPTION
       lvreduce  reduces  the size of an LV. The freed logical extents are re-
       turned to the VG to be used by other LVs. A copy-on-write  snapshot  LV
       can also be reduced if less space is needed to hold COW blocks. Use lv-
       convert(8) to change the number of data images in a  RAID  or  mirrored
       LV.

       Be careful when reducing an LV's size, because data in the reduced area
       is lost. Ensure that any file system on the LV is resized  before  run-
       ning  lvreduce  so  that the removed extents are not in use by the file
       system.

       Sizes will be rounded if necessary. For example, the LV size must be an
       exact  number  of  extents, and the size of a striped segment must be a
       multiple of the number of stripes.

       In the usage section below, --size Size can be replaced with  --extents
       Number.  See both descriptions the options section.

USAGE
       lvreduce -L|--size [-]Size[m|UNIT] LV
           [ -l|--extents [-]Number[PERCENT] ]
           [ -A|--autobackup y|n ]
           [ -f|--force ]
           [ -n|--nofsck ]
           [ -r|--resizefs ]
           [    --noudevsync ]
           [    --reportformat basic|json ]
           [ COMMON_OPTIONS ]

       Common options for lvm:
           [ -d|--debug ]
           [ -h|--help ]
           [ -q|--quiet ]
           [ -t|--test ]
           [ -v|--verbose ]
           [ -y|--yes ]
           [    --commandprofile String ]
           [    --config String ]
           [    --driverloaded y|n ]
           [    --lockopt String ]
           [    --longhelp ]
           [    --nolocking ]
           [    --profile String ]
           [    --version ]

OPTIONS
       -A|--autobackup y|n
              Specifies if metadata should be backed up automatically after a
              change.  Enabling this is strongly advised! See vgcfgbackup(8)
              for more information.

       --commandprofile String
              The command profile to use for command configuration.  See
              lvm.conf(5) for more information about profiles.

       --config String
              Config settings for the command. These override lvm.conf set-
              tings.  The String arg uses the same format as lvm.conf, or may
              use section/field syntax.  See lvm.conf(5) for more information
              about config.

       -d|--debug ...
              Set debug level. Repeat from 1 to 6 times to increase the detail
              of messages sent to the log file and/or syslog (if configured).

       --driverloaded y|n
              If set to no, the command will not attempt to use device-mapper.
              For testing and debugging.

       -l|--extents [-]Number[PERCENT]
              Specifies the new size of the LV in logical extents.  The --size
              and --extents options are alternate methods of specifying size.
              The total number of physical extents used will be greater when
              redundant data is needed for RAID levels.  An alternate syntax
              allows the size to be determined indirectly as a percentage of
              the size of a related VG, LV, or set of PVs. The suffix %VG de-
              notes the total size of the VG, the suffix %FREE the remaining
              free space in the VG, and the suffix %PVS the free space in the
              specified PVs.  For a snapshot, the size can be expressed as a
              percentage of the total size of the origin LV with the suffix
              %ORIGIN (100%ORIGIN provides space for the whole origin).  When
              expressed as a percentage, the size defines an upper limit for
              the number of logical extents in the new LV. The precise number
              of logical extents in the new LV is not determined until the
              command has completed.  When the plus + or minus - prefix is
              used, the value is not an absolute size, but is relative and
              added or subtracted from the current size.

       -f|--force ...
              Override various checks, confirmations and protections.  Use
              with extreme caution.

       -h|--help
              Display help text.

       --lockopt String
              Used to pass options for special cases to lvmlockd.  See lvm-
              lockd(8) for more information.

       --longhelp
              Display long help text.

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

       --nolocking
              Disable locking.

       --noudevsync
              Disables udev synchronisation. The process will not wait for no-
              tification from udev. It will continue irrespective of any pos-
              sible udev processing in the background. Only use this if udev
              is not running or has rules that ignore the devices LVM creates.

       --profile String
              An alias for --commandprofile or --metadataprofile, depending on
              the command.

       -q|--quiet ...
              Suppress output and log messages. Overrides --debug and --ver-
              bose.  Repeat once to also suppress any prompts with answer
              'no'.

       --reportformat basic|json
              Overrides current output format for reports which is defined
              globally by the report/output_format setting in lvm.conf.  basic
              is the original format with columns and rows.  If there is more
              than one report per command, each report is prefixed with the
              report name for identification. json produces report output in
              JSON format. See lvmreport(7) for more information.

       -r|--resizefs
              Resize underlying filesystem together with the LV using
              fsadm(8).

       -L|--size [-]Size[m|UNIT]
              Specifies the new size of the LV.  The --size and --extents op-
              tions are alternate methods of specifying size.  The total num-
              ber of physical extents used will be greater when redundant data
              is needed for RAID levels.  When the plus + or minus - prefix is
              used, the value is not an absolute size, but is relative and
              added or subtracted from the current size.

       -t|--test
              Run in test mode. Commands will not update metadata.  This is
              implemented by disabling all metadata writing but nevertheless
              returning success to the calling function. This may lead to un-
              usual error messages in multi-stage operations if a tool relies
              on reading back metadata it believes has changed but hasn't.

       -v|--verbose ...
              Set verbose level. Repeat from 1 to 4 times to increase the de-
              tail of messages sent to stdout and stderr.

       --version
              Display version information.

       -y|--yes
              Do not prompt for confirmation interactively but always assume
              the answer yes. Use with extreme caution.  (For automatic no,
              see -qq.)

VARIABLES
       LV
              Logical  Volume  name.  See lvm(8) for valid names.  An LV posi-
              tional arg generally includes the VG  name  and  LV  name,  e.g.
              VG/LV.

       String
              See the option description for information about the string con-
              tent.

       Size[UNIT]
              Size is an input number that accepts an  optional  unit.   Input
              units are always treated as base two values, regardless of capi-
              talization, e.g. 'k' and 'K' both refer to  1024.   The  default
              input unit is specified by letter, followed by |UNIT.  UNIT rep-
              resents other possible input units:  bBsSkKmMgGtTpPeE.   b|B  is
              bytes,  s|S  is  sectors  of 512 bytes, k|K is kilobytes, m|M is
              megabytes, g|G is gigabytes, t|T is terabytes, p|P is petabytes,
              e|E  is  exabytes.  (This should not be confused with the output
              control --units, where capital letters mean multiple of 1000.)

ENVIRONMENT VARIABLES
       See lvm(8) for information about environment  variables  used  by  lvm.
       For example, LVM_VG_NAME can generally be substituted for a required VG
       parameter.

EXAMPLES
       Reduce the size of an LV by 3 logical extents:
       lvreduce -l -3 vg00/lvol1

SEE ALSO
       lvm(8) lvm.conf(5) lvmconfig(8)

       pvchange(8)  pvck(8)  pvcreate(8)  pvdisplay(8)  pvmove(8)  pvremove(8)
       pvresize(8) pvs(8) pvscan(8)

       vgcfgbackup(8)  vgcfgrestore(8)  vgchange(8) vgck(8) vgcreate(8) vgcon-
       vert(8)  vgdisplay(8)  vgexport(8)  vgextend(8)  vgimport(8)  vgimport-
       clone(8)  vgmerge(8)  vgmknodes(8)  vgreduce(8) vgremove(8) vgrename(8)
       vgs(8) vgscan(8) vgsplit(8)

       lvcreate(8) lvchange(8)  lvconvert(8)  lvdisplay(8)  lvextend(8)  lvre-
       duce(8) lvremove(8) lvrename(8) lvresize(8) lvs(8) lvscan(8)

       lvm-fullreport(8) lvm-lvpoll(8) lvm2-activation-generator(8) blkdeacti-
       vate(8) lvmdump(8)

       dmeventd(8) lvmpolld(8)  lvmlockd(8)  lvmlockctl(8)  cmirrord(8)  lvmd-
       busd(8)

       lvmsystemid(7) lvmreport(7) lvmraid(7) lvmthin(7) lvmcache(7)

Red Hat, Inc.          LVM TOOLS 2.03.07(2) (2019-11-30)           LVREDUCE(8)

Man(1) output converted with man2html
list of all man pages