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] [--[vg]metadatacopies]
NumberOfCopies|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
--physicalvolumesize 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 vgmetadatacopies 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)