lvreduce(8) — Linux manual page

NAME | SYNOPSIS | DESCRIPTION | USAGE | OPTIONS | VARIABLES | ENVIRONMENT VARIABLES | EXAMPLES | SEE ALSO | COLOPHON

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

NAME         top

       lvreduce — Reduce the size of a logical volume

SYNOPSIS         top

       lvreduce option_args position_args
           [ option_args ]

DESCRIPTION         top

       lvreduce reduces the size of an LV. The freed logical extents are
       returned 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 lvconvert(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 running 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         top

       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 ]
           [    --devices PV ]
           [    --devicesfile String ]
           [    --driverloaded y|n ]
           [    --journal String ]
           [    --lockopt String ]
           [    --longhelp ]
           [    --nohints ]
           [    --nolocking ]
           [    --profile String ]
           [    --version ]

OPTIONS         top


       -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(5) settings.  The String arg uses the same format
              as lvm.conf(5), 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).

       --devices PV
              Devices  that  the  command  can  use.  This option can be
              repeated or accepts a comma  separated  list  of  devices.
              This overrides the devices file.

       --devicesfile String
              A file listing devices that LVM should use.  The file must
              exist   in  /etc/lvm/devices/  and  is  managed  with  the
              lvmdevices(8) command.   This  overrides  the  lvm.conf(5)
              devices/devicesfile  and devices/use_devicesfile settings.

       --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 denotes 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.

       --journal String
              Record  information  in   the   systemd   journal.    This
              information  is  in addition to information enabled by the
              lvm.conf log/journal setting.  command: record information
              about the command.  output:  record  the  default  command
              output.  debug: record full command debugging.

       --lockopt String
              Used  to  pass options for special cases to lvmlockd.  See
              lvmlockd(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.

       --nohints
              Do not use the hints file to locate  devices  for  PVs.  A
              command  may  read more devices to find PVs when hints are
              not used. The command will  still  perform  standard  hint
              file invalidation where appropriate.

       --nolocking
              Disable locking.

       --noudevsync
              Disables  udev  synchronisation. The process will not wait
              for notification from udev. It will continue  irrespective
              of  any  possible  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
              --verbose.   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(5).  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 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.
              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  unusual 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 detail 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         top

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

       String See the option description for information about the
              string content.

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

ENVIRONMENT VARIABLES         top

       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         top

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

SEE ALSO         top

       lvm(8), lvm.conf(5), lvmconfig(8), lvmdevices(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), vgconvert(8), vgdisplay(8), vgexport(8),
       vgextend(8), vgimport(8), vgimportclone(8), vgimportdevices(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), lvreduce(8), lvremove(8), lvrename(8), lvresize(8),
       lvs(8), lvscan(8),

       lvm-fullreport(8), lvm-lvpoll(8), blkdeactivate(8), lvmdump(8),

       dmeventd(8), lvmpolld(8), lvmlockd(8), lvmlockctl(8),
       cmirrord(8), lvmdbusd(8), fsadm(8),

       lvmsystemid(7), lvmreport(7), lvmcache(7), lvmraid(7),
       lvmthin(7), lvmvdo(7), lvmautoactivation(7)

COLOPHON         top

       This page is part of the lvm2 (Logical Volume Manager 2) project.
       Information about the project can be found at 
       ⟨http://www.sourceware.org/lvm2/⟩.  If you have a bug report for
       this manual page, see ⟨https://github.com/lvmteam/lvm2/issues⟩.
       This page was obtained from the project's upstream Git repository
       ⟨git://sourceware.org/git/lvm2.git⟩ on 2024-06-14.  (At that
       time, the date of the most recent commit that was found in the
       repository was 2024-06-11.)  If you discover any rendering
       problems in this HTML version of the page, or you believe there
       is a better or more up-to-date source for the page, or you have
       corrections or improvements to the information in this COLOPHON
       (which is not part of the original manual page), send a mail to
       [email protected]

Red Hat, Inc.     LVM TOOLS 2.03.25(2)-git (2024-05-16)      LVREDUCE(8)

Pages that refer to this page: lvmvdo(7)lvchange(8)lvconvert(8)lvcreate(8)lvdisplay(8)lvextend(8)lvm(8)lvmconfig(8)lvmdevices(8)lvmdiskscan(8)lvm-fullreport(8)lvm-lvpoll(8)lvreduce(8)lvremove(8)lvrename(8)lvresize(8)lvs(8)lvscan(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)vgconvert(8)vgcreate(8)vgdisplay(8)vgexport(8)vgextend(8)vgimport(8)vgimportclone(8)vgimportdevices(8)vgmerge(8)vgmknodes(8)vgreduce(8)vgremove(8)vgrename(8)vgs(8)vgscan(8)vgsplit(8)