pvcreate - initialize a disk or partition for use by LVM
pvcreate [-d|--debug] [-f[f]|--force
[--force]] [-y|--yes] [-h|--help]
[-t|--test] [-v|--verbose] [--labelsector]
[-M|--metadatatypetype]
[--metadatacopies#copies] [--metadatasizesize]
[--restorefilefile] [--setphysicalvolumesizesize]
[-u|--uuiduuid] [--version]
[-Z|--zeroy|n] PhysicalVolume
[PhysicalVolume...]
pvcreate initializes PhysicalVolume for later use by the Logical
Volume Manager (LVM). Each PhysicalVolume can be a disk partition,
whole disk, meta device, or loopback file. For DOS disk partitions, the
partition id should be set to 0x8e using fdisk(8), cfdisk(8), or
a equivalent. For whole disk devices only the partition table must be
erased, which will effectively destroy all data on that disk. This can be done
by zeroing the first sector with:
dd if=/dev/zero of=PhysicalVolume bs=512
count=1
Continue with vgcreate(8) to create a new volume group on
PhysicalVolume, or vgextend(8) to add PhysicalVolume to
an existing volume group.
See lvm(8) for common options.
- -f, --force
- Force the creation without any confirmation. You can not recreate
(reinitialize) a physical volume belonging to an existing volume group. In
an emergency you can override this behaviour with -ff.
- -u, --uuid uuid
- Specify the uuid for the device. Without this option, pvcreate
generates a random uuid. All of your physical volumes must have unique
uuids. You need to use this option before restoring a backup of LVM
metadata onto a replacement device - see vgcfgrestore(8).
- -y, --yes
- Answer yes to all questions.
- -Z, --zero y|n
- Whether or not the first 4 sectors (2048 bytes) of the device should be
wiped. If this option is not given, the default is to wipe these sectors
unless either or both of the --restorefile or --uuid options were
specified.
LVM2 introduces a new format for storing metadata on disk. This new format is
more efficient and resilient than the format the original version of LVM used
and offers the advanced user greater flexibility and control.
The new format may be selected on the command line with -M2
or by setting format = "lvm2" in the global section
of lvm.conf. Each physical volume in the same volume group must use
the same format, but different volume groups on a machine may use different
formats simultaneously: the tools can handle both formats. Additional
formats can be added as shared libraries.
Additional tools for manipulating the locations and sizes of
metadata areas will be written in due course. Use the verbose/debug options
on the tools to see where the metadata areas are placed.
- --metadatasize size
- The approximate amount of space to be set aside for each metadata area.
(The size you specify may get rounded.)
- --metadatacopies copies
- The number of metadata areas to set aside on each PV. Currently this can
be 0, 1 or 2. If set to 2, two copies of the volume group metadata are
held on the PV, one at the front of the PV and one at the end. If set to 1
(the default), one copy is kept at the front of the PV (starting in the
5th sector). If set to 0, no copies are kept on this PV - you might wish
to use this with VGs containing large numbers of PVs. But if you do this
and then later use vgsplit you must ensure that each VG is still
going to have a suitable number of copies of the metadata after the
split!
- --restorefile file
- In conjunction with --uuid, this extracts the location and size of
the data on the PV from the file (produced by vgcfgbackup) and
ensures that the metadata that the program produces is consistent with the
contents of the file i.e. the physical extents will be in the same place
and not get overwritten by new metadata. This provides a mechanism to
upgrade the metadata format or to add/remove metadata areas. Use with
care. See also vgconvert(8).
- --labelsector sector
- By default the PV is labelled with an LVM2 identifier in its second sector
(sector 1). This lets you use a different sector near the start of the
disk (between 0 and 3 inclusive - see LABEL_SCAN_SECTORS in the source).
Use with care.
- --setphysicalvolumesize size
- Overrides the automatically-detected size of the PV. Use with care.
Initialize partition #4 on the third SCSI disk and the entire fifth SCSI disk
for later use by LVM:
pvcreate /dev/sdc4 /dev/sde
lvm(8), vgcreate(8), vgextend(8), lvcreate(8),
cfdisk(8), fdisk(8), losetup(8), mdadm(8),
vgcfgrestore(8), vgconvert(8)