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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|--maxlogicalvolumes MaxLogicalVolumes] [-M|--metadatatypetype]
       [-p|--maxphysicalvolumes MaxPhysicalVolumes] [-s|--physicalextentsize
       PhysicalExtentSize[kKmMgGtT]] [-t|--test] [-v|--verbose] [--version]
       VolumeGroupName PhysicalVolumePath [PhysicalVolumePath...]

DESCRIPTION
       vgcreate creates a new volume group called VolumeGroupName using the
       block special device PhysicalVolumePath previously configured for LVM
       with pvcreate(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
              default value is 0 which 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 --metadatacopies 0 as
              described in pvcreate(8).

       -s, --physicalextentsize PhysicalExtentSize[kKmMgGtT]
              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.

EXAMPLES
       To create a volume group named test_vg using physical volumes
       /dev/hdk1, and /dev/hdl1 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 2.02.44-cvs (02-17-09)            VGCREATE(8)