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



NAME
       vgchange -- change attributes of a volume group

SYNOPSIS
       vgchange	 [--addtag  Tag]  [--alloc  AllocationPolicy] [-A|--autobackup
       {y|n}]  [-a|--activate	[a|e|s|l]   {y|n}]   [--activationmode	 {com-
       plete|degraded|partial}]	 [-K|--ignoreactivationskip] [--monitor {y|n}]
       [--poll {y|n}]  [-c|--clustered	{y|n}]	[-u|--uuid]  [--commandprofile
       ProfileName]  [-d|--debug] [--deltag Tag] [--detachprofile] [-h|--help]
       [--ignorelockingfailure] [--ignoremonitoring]  [--ignoreskippedcluster]
       [--sysinit]  [--noudevsync]  [--lock-start]  [--lock-stop] [--lock-type
       LockType] [-l|--logicalvolume MaxLogicalVolumes]	 [-p|--maxphysicalvol-
       umes  MaxPhysicalVolumes]  [--metadataprofile ProfileName] [--[vg]meta-
       datacopies  NumberOfCopies|unmanaged|all]  [-P|--partial]  [-s|--physi-
       calextentsize   PhysicalExtentSize[bBsSkKmMgGtTpPeE]]   [--reportformat
       {basic|json}] [-S|--select Selection] [--systemid SystemID] [--refresh]
       [-t|--test]  [-v|--verbose]  [--version]	 [-x|--resizeable {y|n}] [Vol-
       umeGroupName...]

DESCRIPTION
       vgchange allows you to change the attributes  of	 one  or  more	volume
       groups. Its main purpose is to activate and deactivate VolumeGroupName,
       or all volume groups if none is specified.  Only active	volume	groups
       are subject to changes and allow access to their logical volumes.  [Not
       yet implemented: During volume group activation, if vgchange recognizes
       snapshot	 logical  volumes  which  were dropped because they ran out of
       space, it displays a message  informing	the  administrator  that  such
       snapshots should be removed (see lvremove(8)).  ]

OPTIONS
       See lvm(8) for common options.

       -A, --autobackup {y|n}
	      Controls	automatic  backup  of  metadata after the change.  See
	      vgcfgbackup(8).  Default is yes.

       -a, --activate [a|e|s|l]{y|n}
	      Controls the availability of the logical volumes in  the	volume
	      group  for input/output.	In other words, makes the logical vol-
	      umes known/unknown to the kernel.	 If autoactivation  option  is
	      used  (-aay),  each  logical volume in the volume group is acti-
	      vated only if it matches an item in the  activation/auto_activa-
	      tion_volume_list	set in lvm.conf. If this list is not set, then
	      all volumes are considered  for  activation.   The  -aay	option
	      should  be  also	used  during  system  boot so it's possible to
	      select which volumes to activate using the activation/auto_acti-
	      vation_volume_list settting.

	      Activation of a logical volume creates a symbolic link /dev/Vol-
	      umeGroupName/LogicalVolumeName  pointing	to  the	 device	 node.
	      This  link is removed on deactivation.  All software and scripts
	      should access the device through this symbolic link and  present
	      this  as	the  name of the device.  The location and name of the
	      underlying device node may depend on the distribution  and  con-
	      figuration (e.g. udev) and might change from release to release.

	      In a clustered VG, clvmd is used for activation, and the follow-
	      ing options are possible:

	      With -aey, clvmd activates the LV in  exclusive  mode  (with  an
	      exclusive lock), allowing a single node to activate the LV.

	      With  -asy, clvmd activates the LV in shared mode (with a shared
	      lock), allowing multiple nodes to activate the LV	 concurrently.
	      If  the  LV  type	 prohibits shared access, such as an LV with a
	      snapshot, the 's' option is ignored and  an  exclusive  lock  is
	      used.

	      With  -ay	 (no mode specified), clvmd activates the LV in shared
	      mode if the LV type allows concurrent access, such as  a	linear
	      LV.  Otherwise, clvmd activates the LV in exclusive mode.

	      With  -aey,  -asy, and -ay, clvmd attempts to activate the LV on
	      all nodes.  If exclusive mode is used,  then  only  one  of  the
	      nodes will be successful.

	      With -an, clvmd attempts to deactivate the LV on all nodes.

	      With  -aly,  clvmd  activates the LV only on the local node, and
	      -aln deactivates only on the local node.	If the LV type	allows
	      concurrent  access,  then	 shared mode is used, otherwise exclu-
	      sive.

	      LVs with snapshots are always activated exclusively because they
	      can only be used on one node at once.

	      For local VGs, -ay, -aey, and -asy are all equivalent.

	      In  a shared VG, lvmlockd is used for locking if LVM is compiled
	      with lockd support, and the following options are possible:

	      With -aey, the command  activates	 the  LV  in  exclusive	 mode,
	      allowing	a single host to activate the LV (the host running the
	      command).	 Before activating the LV, the command	uses  lvmlockd
	      to  acquire  an exclusive lock on the LV.	 If the lock cannot be
	      acquired, the LV is not activated	 and  an  error	 is  reported.
	      This would happen if the LV is active on another host.

	      With -asy, the command activates the LV in shared mode, allowing
	      multiple hosts to activate the LV concurrently.  Before activat-
	      ing  the	LV, the command uses lvmlockd to acquire a shared lock
	      on the LV.  If the lock cannot be acquired, the LV is not	 acti-
	      vated  and an error is reported.	This would happen if the LV is
	      active exclusively on another host.  If the  LV  type  prohibits
	      shared  access,  such  as a snapshot, the command will report an
	      error and fail.

	      With -an, the command deactivates the LV on the host running the
	      command.	 After	deactivating the LV, the command uses lvmlockd
	      to release the current lock on the LV.

	      With lvmlockd, an unspecified  mode  is  always  exclusive,  -ay
	      defaults to -aey.


       --activationmode {complete|degraded|partial}
	      The  activation  mode  determines	 whether  logical  volumes are
	      allowed to activate when	there  are  physical  volumes  missing
	      (e.g.  due  to a device failure).	 complete is the most restric-
	      tive; allowing only those logical volumes to be  activated  that
	      are not affected by the missing PVs.  degraded allows RAID logi-
	      cal volumes to be activated  even	 if  they  have	 PVs  missing.
	      (Note  that  the	"mirror" segment type is not considered a RAID
	      logical  volume.	 The  "raid1"  segment	type  should  be  used
	      instead.)	  Finally,  partial  allows  any  logical volume to be
	      activated even if portions are  missing  due  to	a  missing  or
	      failed PV.  This last option should only be used when performing
	      recovery or repair operations.  degraded is  the	default	 mode.
	      To change it, modify activation_mode in lvm.conf(5).

       -K, --ignoreactivationskip
	      Ignore the flag to skip Logical Volumes during activation.

       -c, --clustered {y|n}
	      If  clustered  locking  is  enabled, this indicates whether this
	      Volume Group is shared  with  other  nodes  in  the  cluster  or
	      whether it contains only local disks that are not visible on the
	      other nodes.  If the cluster infrastructure is unavailable on  a
	      particular  node	at a particular time, you may still be able to
	      use Volume Groups that are not marked as clustered.

       --detachprofile
	      Detach any metadata configuration	 profiles  attached  to	 given
	      Volume  Groups. See lvm.conf(5) for more information about meta-
	      data profiles.

       -u, --uuid
	      Generate new random UUID for specified Volume Groups.

       --monitor {y|n}
	      Start or stop monitoring a mirrored or snapshot  logical	volume
	      with  dmeventd, if it is installed.  If a device used by a moni-
	      tored mirror reports  an	I/O  error,  the  failure  is  handled
	      according to mirror_image_fault_policy and mirror_log_fault_pol-
	      icy set in lvm.conf(5).

       --poll {y|n}
	      Without polling a logical volume's  backgrounded	transformation
	      process  will  never complete.  If there is an incomplete pvmove
	      or lvconvert (for example, on  rebooting	after  a  crash),  use
	      --poll  y to restart the process from its last checkpoint.  How-
	      ever, it may not be appropriate to immediately  poll  a  logical
	      volume  when  it	is  activated,	use --poll n to defer and then
	      --poll y to restart the process.

       --sysinit
	      Indicates that vgchange(8) is being invoked  from	 early	system
	      initialisation  scripts  (e.g.  rc.sysinit or an initrd), before
	      writeable filesystems are available. As such, some functionality
	      needs  to	 be  disabled and this option acts as a shortcut which
	      selects an appropriate set of options. Currently this is equiva-
	      lent to using --ignorelockingfailure, --ignoremonitoring, --poll
	      n and setting LVM_SUPPRESS_LOCKING_FAILURE_MESSAGES  environment
	      variable.

	      If  --sysinit is used in conjunction with lvmetad(8) enabled and
	      running, autoactivation is preferred over manual activation  via
	      direct vgchange call.  Logical volumes are autoactivated accord-
	      ing to auto_activation_volume_list set in lvm.conf(5).

       --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.

       --ignoremonitoring
	      Make no attempt to interact with dmeventd	 unless	 --monitor  is
	      specified.   Do not use this if dmeventd is already monitoring a
	      device.

       --lock-start
	      Start the lockspace of a shared VG in lvmlockd.  lvmlockd	 locks
	      becomes  available  for the VG, allowing LVM to use the VG.  See
	      lvmlockd(8).

       --lock-stop
	      Stop the lockspace of a shared VG in lvmlockd.   lvmlockd	 locks
	      become unavailable for the VG, preventing LVM from using the VG.
	      See lvmlockd(8).

       --lock-type LockType
	      Change the VG lock type to or from a shared lock type used  with
	      lvmlockd.	 See lvmlockd(8).

       -l, --logicalvolume MaxLogicalVolumes
	      Changes  the  maximum logical volume number of an existing inac-
	      tive volume group.

       -p, --maxphysicalvolumes MaxPhysicalVolumes
	      Changes the maximum number of physical volumes that  can	belong
	      to  this	volume group.  For volume groups with metadata in lvm1
	      format, the limit is 255.	 If the metadata uses lvm2 format, the
	      value  0	removes	 this restriction: there is then no limit.  If
	      you have a large number of physical volumes in  a	 volume	 group
	      with  metadata in lvm2 format, for tool performance reasons, you
	      should consider some use of --pvmetadatacopies 0 as described in
	      pvcreate(8), and/or use --vgmetadatacopies.

       --metadataprofile ProfileName
	      Uses  and attaches ProfileName configuration profile to the vol-
	      ume group metadata. Whenever the volume group is processed  next
	      time,  the  profile  is  automatically  applied.	The profile is
	      inherited by all logical volumes in the volume group unless  the
	      logical	volume	itself	has  its  own  profile	attached.  See
	      lvm.conf(5) for more information about metadata profiles.

       --[vg]metadatacopies NumberOfCopies|unmanaged|all
	      Sets the desired number of metadata copies in the volume	group.
	      If  set  to  a non-zero value, LVM will automatically manage the
	      'metadataignore' flags on the physical volumes (see pvchange  or
	      pvcreate	--metadataignore)  in  order to achieve NumberOfCopies
	      copies of metadata.  If set to unmanaged, LVM will not automati-
	      cally  manage  the  'metadataignore'  flags.  If set to all, LVM
	      will first clear all of the 'metadataignore' flags on all	 meta-
	      data areas in the volume group, then set the value to unmanaged.
	      The vgmetadatacopies option is useful for volume groups contain-
	      ing large numbers of physical volumes with metadata as it may be
	      used to minimize metadata read and write overhead.

       -s, --physicalextentsize PhysicalExtentSize[BbBsSkKmMgGtTpPeE]
	      Changes the physical extent size on  physical  volumes  of  this
	      volume  group.   A size suffix (k for kilobytes up to t for ter-
	      abytes) is optional, megabytes is the default if	no  suffix  is
	      present.	 For LVM2 format, the value must be a power of 2 of at
	      least 1 sector (where the sector size is the largest sector size
	      of the PVs currently used in the VG) or, if not a power of 2, at
	      least 128KiB.  For the older LVM1 format, it must be a power  of
	      2 of at least 8KiB.  The default is 4 MiB.

	      Before  increasing  the  physical extent size, you might need to
	      use lvresize, pvresize and/or pvmove so  that  everything	 fits.
	      For example, every contiguous range of extents used in a logical
	      volume must start and end on an extent boundary.

	      If the volume group metadata uses lvm1 format, extents can  vary
	      in size from 8KiB to 16GiB and there is a limit of 65534 extents
	      in each logical volume.  The default of 4 MiB leads to a maximum
	      logical volume size of around 256GiB.

	      If the volume group metadata uses lvm2 format those restrictions
	      do not apply, but having a large number  of  extents  will  slow
	      down the tools but have no impact on I/O performance to the log-
	      ical volume.  The smallest PE is 1KiB.

	      The 2.4 kernel has a limitation of 2TiB per block device.

       --systemid SystemID
	      Changes the system ID of the VG.	 Using	this  option  requires
	      caution  because	the  VG may become foreign to the host running
	      the command, leaving the host unable to access it.  See  lvmsys-
	      temid(7).

       --refresh
	      If  any logical volume in the volume group is active, reload its
	      metadata.	 This is not necessary in normal operation, but may be
	      useful if something has gone wrong or if you're doing clustering
	      manually without a clustered lock manager.

       -x, --resizeable {y|n}
	      Enables or disables the extension/reduction of this volume group
	      with/by physical volumes.

Examples
       To activate all known volume groups in the system:

       vgchange -a y

       To  change  the	maximum	 number	 of logical volumes of inactive volume
       group vg00 to 128.

       vgchange -l 128 /dev/vg00



SEE ALSO
       lvchange(8), lvm(8), vgcreate(8)



Sistina Software UKLVM TOOLS 2.02.166(2)-RHEL7 (2016-11-16)	   VGCHANGE(8)