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vgchange(8) [bsd man page]

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|--available [e|l] {y|n}] [--monitor {y|n}] [--poll {y|n}]
       [-c|--clustered {y|n}] [-u|--uuid]  [-d|--debug]  [--deltag  Tag]  [-h|--help]  [--ignorelockingfailure]  [--ignoremonitoring]  [--sysinit]
       [--noudevsync]	[-l|--logicalvolume   MaxLogicalVolumes]  [-p|--maxphysicalvolumes  MaxPhysicalVolumes]  [--[vg]metadatacopies]  NumberOf-
       Copies|unmanaged|all] [-P|--partial] [-s|--physicalextentsize PhysicalExtentSize[bBsSkKmMgGtTpPeE]] [--refresh] [-t|--test]  [-v|--verbose]
       [--version] [-x|--resizeable {y|n}] [VolumeGroupName...]

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 for common options.

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

       -a, --available [e|l]{y|n}
	      Controls the availability of the logical volumes in the volume group for input/output.  In other words, makes  the  logical  volumes
	      known/unknown to the kernel.

	      If  clustered  locking  is enabled, add 'e' to activate/deactivate exclusively on one node or 'l' to activate/deactivate only on the
	      local node.  Logical volumes with single-host snapshots are always activated exclusively because they can only be used on  one  node
	      at once.

       -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.

       -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 monitored
	      mirror reports an I/O error, the failure is handled  according  to  mirror_image_fault_policy  and  mirror_log_fault_policy  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.  However, 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  write-
	      able 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 equivalent to using  --ignorelockingfailure, --ignoremonitoring, --poll n and  setting
	      LVM_SUPPRESS_LOCKING_FAILURE_MESSAGES environment variable.

       --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  cre-
	      ates.

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

       -l, --logicalvolume MaxLogicalVolumes
	      Changes the maximum logical volume number of an existing inactive 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  for-
	      mat, 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.

       --[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 automatically manage the 'metadataignore' flags.  If set to all, LVM will first
	      clear all of the 'metadataignore' flags on all metadata areas in the volume group, then set the value to unmanaged.  The vgmetadata-
	      copies  option  is useful for volume groups containing large numbers of physical volumes with metadata as it may be used to minimize
	      metadata read and write overhead.

       -s, --physicalextentsize PhysicalExtentSize[bBsSkKmMgGtTpPeE]
	      Changes the physical extent size on physical volumes of this volume group.  A size suffix (k for kilobytes up to t for terabytes) is
	      optional, megabytes is the default if no suffix is present.  The default is 4 MB and it must be at least 1 KB and a power of 2.

	      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 8KB to 16GB and there is a limit of	65534  extents	in
	      each logical volume.  The default of 4 MB leads to a maximum logical volume size of around 256GB.

	      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 logical volume.  The smallest PE is 1KB.

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

       --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 UK					 LVM TOOLS 2.02.95(2) (2012-03-06)					       VGCHANGE(8)

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