Linux and UNIX Man Pages

Linux & Unix Commands - Search Man Pages

pvcreate(8) [bsd man page]

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

       pvcreate - initialize a disk or partition for use by LVM

       pvcreate  [-d|--debug]  [-h|--help] [-t|--test] [-v|--verbose] [--version] [-f[f]|--force [--force]] [-y|--yes] [--labelsector] [-M|--meta-
       datatype type] [--[pv]metadatacopies #copies] [--metadatasize size]  [--metadataignore  {y|n}]  [--dataalignment  alignment]  [--dataalign-
       mentoffset alignment_offset] [--restorefile file] [--norestorefile] [--setphysicalvolumesize size] [-u|--uuid uuid] [-Z|--zero {y|n}] Phys-
       icalVolume [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 vgcfgre-
	      store(8).  As such, use of --restorefile is compulsory unless the --norestorefile is used.

       -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 simultane-
       ously: 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.)

       --dataalignment alignment
	      Align  the  start of the data to a multiple of this number.  You should also specify an appropriate PhysicalExtentSize when creating
	      the Volume Group with vgcreate.

	      To see the location of the first Physical Extent of an existing Physical Volume use pvs -o +pe_start .  It will be a multiple of the
	      requested  alignment.   In  addition  it	may  be  shifted  by  alignment_offset from data_alignment_offset_detection (if enabled in
	      lvm.conf) or --dataalignmentoffset.

       --dataalignmentoffset alignment_offset
	      Shift the start of the data area by this additional alignment_offset.

       --[pv]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 con-
	      taining  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!

       --metadataignore y|n
	      Ignore or un-ignore metadata areas on this physical volume.  The default is "n".	This setting can be  changed  with  pvchange.	If
	      metadata	areas on a physical volume are ignored, LVM will not store metadata in the metadata areas present on this Physical Volume.
	      Metadata areas cannot be created or extended after Logical Volumes have been allocated on the device. If you do not  want  to  store
	      metadata	on  this  device,  it  is  still wise always to allocate a metadata area in case you need it in the future and to use this
	      option to instruct LVM2 to ignore it.

       --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).

	      In conjunction with --uuid, this allows a uuid to be specified without also requiring that a backup of the metadata be provided.

       --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

       If the 2nd SCSI disk is a 4KB sector drive that compensates for windows partitioning (sector 7 is the lowest aligned logical block, the 4KB
       sectors	start  at  LBA -1, and consequently sector 63 is aligned on a 4KB boundary) manually account for this when initializing for use by

       pvcreate --dataalignmentoffset 7s /dev/sdb

       lvm.conf(5), lvm(8), vgcreate(8), vgextend(8), lvcreate(8), cfdisk(8), fdisk(8), losetup(8), mdadm(8), vgcfgrestore(8), vgconvert(8)

Sistina Software UK					 LVM TOOLS 2.02.95(2) (2012-03-06)					       PVCREATE(8)
Man Page