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vgcreate(8) [bsd man page]

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

NAME
       vgcreate - create a volume group

SYNOPSIS
       vgcreate  [--addtag  Tag] [--alloc AllocationPolicy] [-A|--autobackup {y|n}] [-c|--clustered {y|n}] [-d|--debug] [-h|--help] [-l|--maxlogi-
       calvolumes  MaxLogicalVolumes]  [-M|--metadatatypetype]	[-p|--maxphysicalvolumes  MaxPhysicalVolumes]	[--[vg]metadatacopies]	 NumberOf-
       Copies|unmanaged|all]  [-s|--physicalextentsize	PhysicalExtentSize[bBsSkKmMgGtTpPeE]]  [-t|--test]  [-v|--verbose]  [--version] [ PHYSICAL
       DEVICE OPTIONS ] VolumeGroupName PhysicalDevicePath [PhysicalDevicePath...]

DESCRIPTION
       vgcreate creates a new volume group called VolumeGroupName using the block special device PhysicalDevicePath.

       If PhysicalDevicePath was not previously configured for LVM with pvcreate (8), the device will be initialized with the same default  values
       used  with  pvcreate.   If non-default pvcreate values are desired, they may be given on the commandline with the same options as pvcreate.
       See PHYSICAL DEVICE OPTIONS for available options.  Note that the restore-related options such as --restorefile, --uuid, and --physicalvol-
       umesize are not available.  If a restore operation is needed, use pvcreate (8) and vgcfgrestore (8).

OPTIONS
       See lvm for common options.

       -c, --clustered {y|n}
	      If clustered locking is enabled, this defaults to y indicating that this Volume Group is shared with other nodes in the cluster.

	      If  the  new Volume Group contains only local disks that are not visible on the other nodes, you must specify --clustered n.  If the
	      cluster infrastructure is unavailable on a particular node at a particular time, you may still be able to use such Volume Groups.

       -l, --maxlogicalvolumes MaxLogicalVolumes
	      Sets the maximum number of logical volumes allowed in this volume group.	The setting can be  changed  with  vgchange.   For  volume
	      groups  with  metadata in lvm1 format, the limit and default value is 255.  If the metadata uses lvm2 format, the default value is 0
	      which removes this restriction: there is then no limit.

       -p, --maxphysicalvolumes MaxPhysicalVolumes
	      Sets the maximum number of physical volumes that can belong to this volume group.  The setting can be changed  with  vgchange.   For
	      volume  groups  with  metadata  in  lvm1	format, the limit and default value 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.

       --vgmetadatacopies 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 pvcreate or pvchange --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.  The default value is unmanaged.

       -s, --physicalextentsize PhysicalExtentSize[bBsSkKmMgGtTpPeE]
	      Sets  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.

	      Once this value has been set, it is difficult to change it without recreating the volume group which would involve  backing  up  and
	      restoring  data  on  any	logical  volumes.   However, if no extents need moving for the new value to apply, it can be altered using
	      vgchange -s.

	      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.

PHYSICAL DEVICE OPTIONS
       The following options are available for initializing physical devices in the volume group.  These options  are  further	described  in  the
       pvcreate man page.

       -f, --force

       -y, --yes

       -Z, --zero y|n

       --labelsector sector

       --metadatasize size

       --pvmetadatacopies copies

       --dataalignment alignment

       --dataalignmentoffset alignment_offset

EXAMPLES
       To create a volume group named test_vg using physical volumes /dev/sdk1, and /dev/sdl1 with default physical extent size of 4MB:

	    vgcreate test_vg /dev/sdk1 /dev/sdl1

SEE ALSO
       lvm(8), pvdisplay(8), pvcreate(8), vgdisplay(8), vgextend(8), vgreduce(8), lvcreate(8), lvdisplay(8), lvextend(8), lvreduce(8)

Sistina Software UK					 LVM TOOLS 2.02.95(2) (2012-03-06)					       VGCREATE(8)

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