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

NAME
       pvcreate - Initialize physical volume(s) for use by LVM

SYNOPSIS
       pvcreate position_args
           [ option_args ]

DESCRIPTION
       pvcreate  initializes  a Physical Volume (PV) on a device so the device
       is recognized as belonging to LVM.  This allows the PV to be used in  a
       Volume Group (VG).  An LVM disk label is written to the device, and LVM
       metadata areas are initialized.  A PV can be placed on a  whole  device
       or partition.

       Use vgcreate(8) to create a new VG on the PV, or vgextend(8) to add the
       PV to an existing VG.  Use pvremove(8) to remove  the  LVM  disk  label
       from the device.

       The  force option will create a PV without confirmation.  Repeating the
       force option (-ff) will forcibly create a PV,  overriding  checks  that
       normally prevent it, e.g. if the PV is already in a VG.

       Metadata location, size, and alignment

       The  LVM  disk label begins 512 bytes from the start of the device, and
       is 512 bytes in size.

       The LVM metadata area begins at an offset (from the start  of  the  de-
       vice)  equal  to  the page size of the machine creating the PV (often 4
       KiB.) The metadata area contains a 512 byte header and a multi-KiB cir-
       cular buffer that holds text copies of the VG metadata.

       With  default  settings, the first physical extent (PE), which contains
       LV data, is 1 MiB from the start of the device.  This location is  con-
       trolled  by default_data_alignment in lvm.conf, which is set to 1 (MiB)
       by default.  The pe_start will be a multiple of this  many  MiB.   This
       location can be checked with:
       pvs -o pe_start PV

       The size of the LVM metadata area is the space between the the start of
       the metadata area and the first PE.  When metadata begins at 4 KiB  and
       the  first PE is at 1024 KiB, the metadata area size is 1020 KiB.  This
       can be checked with:
       pvs -o mda_size PV

       The mda_size cannot be increased after pvcreate, so if larger  metadata
       is  needed, it must be set during pvcreate.  Two copies of the VG meta-
       data must always fit within the metadata area, so the maximum VG  meta-
       data size is around half the mda_size.  This can be checked with:
       vgs -o mda_free VG

       A  larger  metadata area can be set with --metadatasize.  The resulting
       mda_size may be larger than  specified  due  to  default_data_alignment
       placing pe_start on a MiB boundary, and the fact that the metadata area
       extends to the first PE.  With metadata  starting  at  4  KiB  and  de-
       fault_data_alignment  1  (MiB), setting --metadatasize 2048k results in
       pe_start of 3 MiB and mda_size of 3068 KiB.  Alternatively, --metadata-
       size 2044k results in pe_start at 2 MiB and mda_size of 2044 KiB.

       The  alignment of pe_start described above may be automatically overri-
       den based on md device properties or device i/o properties reported  in
       sysfs.   These  automatic  adjustments  can  be  enabled/disabled using
       lvm.conf settings md_chunk_alignment  and  data_alignment_offset_detec-
       tion.

       To  use a different pe_start alignment, use the --dataalignment option.
       The --metadatasize option would also typically be used in this case be-
       cause  the metadata area size also determines the location of pe_start.
       When using these two options together, pe_start is calculated as: meta-
       data area start (page size), plus the specified --metadatasize, rounded
       up to the next multiple of --dataalignment.  With metadata starting  at
       4 KiB, --metadatasize 2048k, and --dataalignment 128k, pe_start is 2176
       KiB and mda_size is 2172 KiB.  The pe_start of 2176 KiB is the  nearest
       even  multiple  of  128 KiB that provides at least 2048 KiB of metadata
       space.  Always check the resulting alignment and metadata size when us-
       ing these options.

       To  shift  an  aligned pe_start value, use the --dataaligmentoffset op-
       tion.  The pe_start alignment is calculated  as  described  above,  and
       then  the value specified with --dataaligmentoffset is added to produce
       the final pe_start value.

USAGE
       pvcreate PV ...
           [ -f|--force ]
           [ -M|--metadatatype lvm2 ]
           [ -u|--uuid String ]
           [ -Z|--zero y|n ]
           [    --dataalignment Size[k|UNIT] ]
           [    --dataalignmentoffset Size[k|UNIT] ]
           [    --bootloaderareasize Size[m|UNIT] ]
           [    --labelsector Number ]
           [    --[pv]metadatacopies 0|1|2 ]
           [    --metadatasize Size[m|UNIT] ]
           [    --metadataignore y|n ]
           [    --norestorefile ]
           [    --setphysicalvolumesize Size[m|UNIT] ]
           [    --reportformat basic|json ]
           [    --restorefile String ]
           [ COMMON_OPTIONS ]

       Common options for lvm:
           [ -d|--debug ]
           [ -h|--help ]
           [ -q|--quiet ]
           [ -t|--test ]
           [ -v|--verbose ]
           [ -y|--yes ]
           [    --commandprofile String ]
           [    --config String ]
           [    --driverloaded y|n ]
           [    --lockopt String ]
           [    --longhelp ]
           [    --nolocking ]
           [    --profile String ]
           [    --version ]

OPTIONS
       --bootloaderareasize Size[m|UNIT]
              Reserve space for the bootloader between the LVM metadata area
              and the first PE.  The bootloader area is reserved for bootload-
              ers to embed their own data or metadata; LVM will not use it.
              The bootloader area begins where the first PE would otherwise be
              located.  The first PE is moved out by the size of the boot-
              loader area, and then moved out further if necessary to match
              the data alignment.  The start of the bootloader area is always
              aligned, see also --dataalignment and --dataalignmentoffset. The
              bootloader area may be larger than requested due to the align-
              ment, but it's never less than the requested size.  To see the
              bootloader area start and size of an existing PV use pvs -o
              +pv_ba_start,pv_ba_size.

       --commandprofile String
              The command profile to use for command configuration.  See
              lvm.conf(5) for more information about profiles.

       --config String
              Config settings for the command. These override lvm.conf set-
              tings.  The String arg uses the same format as lvm.conf, or may
              use section/field syntax.  See lvm.conf(5) for more information
              about config.

       --dataalignment Size[k|UNIT]
              Align the start of a PV data area with a multiple of this num-
              ber.  To see the location of the first Physical Extent (PE) of
              an existing PV, use pvs -o +pe_start. In addition, it may be
              shifted by an alignment offset, see --dataalignmentoffset.  Also
              specify an appropriate PE size when creating a VG.

       --dataalignmentoffset Size[k|UNIT]
              Shift the start of the PV data area by this additional offset.

       -d|--debug ...
              Set debug level. Repeat from 1 to 6 times to increase the detail
              of messages sent to the log file and/or syslog (if configured).

       --driverloaded y|n
              If set to no, the command will not attempt to use device-mapper.
              For testing and debugging.

       -f|--force ...
              Override various checks, confirmations and protections.  Use
              with extreme caution.

       -h|--help
              Display help text.

       --labelsector Number
              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 LA-
              BEL_SCAN_SECTORS in the source). Use with care.

       --lockopt String
              Used to pass options for special cases to lvmlockd.  See lvm-
              lockd(8) for more information.

       --longhelp
              Display long help text.

       --metadataignore y|n
              Specifies the metadataignore property of a PV.  If yes, metadata
              areas on the PV are ignored, and lvm will not store metadata in
              the metadata areas of the PV.  If no, lvm will store metadata on
              the PV.

       --metadatasize Size[m|UNIT]
              The approximate amount of space used for each VG metadata area.
              The size may be rounded.

       -M|--metadatatype lvm2
              Specifies the type of on-disk metadata to use.  lvm2 (or just 2)
              is the current, standard format.  lvm1 (or just 1) is no longer
              used.

       --nolocking
              Disable locking.

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

       --profile String
              An alias for --commandprofile or --metadataprofile, depending on
              the command.

       --[pv]metadatacopies 0|1|2
              The number of metadata areas to set aside on a PV for storing VG
              metadata.  When 2, one copy of the VG metadata is stored at the
              front of the PV and a second copy is stored at the end.  When 1,
              one copy of the VG metadata is stored at the front of the PV.
              When 0, no copies of the VG metadata are stored on the given PV.
              This may be useful in VGs containing many PVs (this places limi-
              tations on the ability to use vgsplit later.)

       -q|--quiet ...
              Suppress output and log messages. Overrides --debug and --ver-
              bose.  Repeat once to also suppress any prompts with answer
              'no'.

       --reportformat basic|json
              Overrides current output format for reports which is defined
              globally by the report/output_format setting in lvm.conf.  basic
              is the original format with columns and rows.  If there is more
              than one report per command, each report is prefixed with the
              report name for identification. json produces report output in
              JSON format. See lvmreport(7) for more information.

       --restorefile String
              In conjunction with --uuid, this reads the file (produced by
              vgcfgbackup), extracts the location and size of the data on the
              PV, and ensures that the metadata produced by the program is
              consistent with the contents of the file, i.e. the physical ex-
              tents will be in the same place and not be overwritten by new
              metadata. This provides a mechanism to upgrade the metadata for-
              mat or to add/remove metadata areas. Use with care.

       --setphysicalvolumesize Size[m|UNIT]
              Overrides the automatically detected size of the PV.  Use with
              care, or prior to reducing the physical size of the device.

       -t|--test
              Run in test mode. Commands will not update metadata.  This is
              implemented by disabling all metadata writing but nevertheless
              returning success to the calling function. This may lead to un-
              usual error messages in multi-stage operations if a tool relies
              on reading back metadata it believes has changed but hasn't.

       -u|--uuid String
              Specify a UUID for the device.  Without this option, a random
              UUID is generated.  This option is needed 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.  All PVs must have unique UUIDs, and
              LVM will prevent certain operations if multiple devices are seen
              with the same UUID.  See vgimportclone(8) for more information.

       -v|--verbose ...
              Set verbose level. Repeat from 1 to 4 times to increase the de-
              tail of messages sent to stdout and stderr.

       --version
              Display version information.

       -y|--yes
              Do not prompt for confirmation interactively but always assume
              the answer yes. Use with extreme caution.  (For automatic no,
              see -qq.)

       -Z|--zero y|n
              Controls if the first 4 sectors (2048 bytes) of the device are
              wiped.  The default is to wipe these sectors unless either or
              both of --restorefile or --uuid are specified.

VARIABLES
       PV
              Physical Volume name, a device path under  /dev.   For  commands
              managing physical extents, a PV positional arg generally accepts
              a suffix indicating a range (or multiple ranges) of physical ex-
              tents  (PEs).  When  the first PE is omitted, it defaults to the
              start of the device, and when the last PE is omitted it defaults
              to  end.   Start and end range (inclusive): PV[:PE-PE]...  Start
              and length range (counting from 0): PV[:PE+PE]...

       String
              See the option description for information about the string con-
              tent.

       Size[UNIT]
              Size  is  an  input number that accepts an optional unit.  Input
              units are always treated as base two values, regardless of capi-
              talization,  e.g.  'k'  and 'K' both refer to 1024.  The default
              input unit is specified by letter, followed by |UNIT.  UNIT rep-
              resents  other  possible  input units: bBsSkKmMgGtTpPeE.  b|B is
              bytes, s|S is sectors of 512 bytes, k|K  is  kilobytes,  m|M  is
              megabytes, g|G is gigabytes, t|T is terabytes, p|P is petabytes,
              e|E is exabytes.  (This should not be confused with  the  output
              control --units, where capital letters mean multiple of 1000.)

ENVIRONMENT VARIABLES
       See  lvm(8)  for  information  about environment variables used by lvm.
       For example, LVM_VG_NAME can generally be substituted for a required VG
       parameter.

EXAMPLES
       Initialize a partition and a full device.
       pvcreate /dev/sdc4 /dev/sde

       If  a device is a 4KiB sector drive that compensates for windows parti-
       tioning (sector 7 is the lowest aligned logical block, the 4KiB sectors
       start at LBA -1, and consequently sector 63 is aligned on a 4KiB bound-
       ary) manually account for this when initializing for use by LVM.
       pvcreate --dataalignmentoffset 7s /dev/sdb

SEE ALSO
       lvm(8) lvm.conf(5) lvmconfig(8)

       pvchange(8)  pvck(8)  pvcreate(8)  pvdisplay(8)  pvmove(8)  pvremove(8)
       pvresize(8) pvs(8) pvscan(8)

       vgcfgbackup(8)  vgcfgrestore(8)  vgchange(8) vgck(8) vgcreate(8) vgcon-
       vert(8)  vgdisplay(8)  vgexport(8)  vgextend(8)  vgimport(8)  vgimport-
       clone(8)  vgmerge(8)  vgmknodes(8)  vgreduce(8) vgremove(8) vgrename(8)
       vgs(8) vgscan(8) vgsplit(8)

       lvcreate(8) lvchange(8)  lvconvert(8)  lvdisplay(8)  lvextend(8)  lvre-
       duce(8) lvremove(8) lvrename(8) lvresize(8) lvs(8) lvscan(8)

       lvm-fullreport(8) lvm-lvpoll(8) lvm2-activation-generator(8) blkdeacti-
       vate(8) lvmdump(8)

       dmeventd(8) lvmpolld(8)  lvmlockd(8)  lvmlockctl(8)  cmirrord(8)  lvmd-
       busd(8)

       lvmsystemid(7) lvmreport(7) lvmraid(7) lvmthin(7) lvmcache(7)

Red Hat, Inc.          LVM TOOLS 2.03.07(2) (2019-11-30)           PVCREATE(8)

NAME | SYNOPSIS | DESCRIPTION | USAGE | OPTIONS | VARIABLES | ENVIRONMENT VARIABLES | EXAMPLES | SEE ALSO