NAME¶
vgcreate — create a volume group
SYNOPSIS¶
vgcreate [
--addtag Tag] [
--alloc
AllocationPolicy] [
-A|
--autobackup {
y|
n}]
[
-c|
--clustered {
y|
n}] [
--commandprofile
ProfileName] [
-d|
--debug] [
-h|
--help]
[
-l|
--maxlogicalvolumes MaxLogicalVolumes]
[
-M|
--metadatatype type] [
--metadataprofile
ProfileName] [
-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(8). If non-default
pvcreate values are
desired, they may be given on the commandline with the same options as
pvcreate(8). 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(8) 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(8). 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.
- --[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 pvcreate(8) 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.
- --metadataprofile ProfileName
- Uses and attaches the ProfileName configuration profile to the volume
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.
- -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 value must be at least 1
sector for LVM2 format (where the sector size is the largest sector size
of the PVs currently used in the VG) or 8KiB for LVM1 format and it must
be a power of 2. The default is 4 MiB.
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
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 logical volume. The smallest PE
is 1KiB
The 2.4 kernel has a limitation of 2TiB 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(8)
man page.
- -f, --force
- -y, --yes
- -Z, --zero
{y|n}
- --labelsector sector
- --metadatasize size
- --pvmetadatacopies copies
- --dataalignment alignment
- --dataalignmentoffset alignment_offset
Examples¶
Creates a volume group named "test_vg" using physical volumes
"/dev/sdk1" and "/dev/sdl1" with default physical extent
size of 4MiB:
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)