pvcreate(8) — Linux manual page


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

NAME         top

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

SYNOPSIS         top

       pvcreate position_args
           [ option_args ]

DESCRIPTION         top

       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
       device) 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
       circular 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
       controlled 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 metadata must always fit within the metadata area, so the
       maximum VG metadata 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
       default_data_alignment 1 (MiB), setting --metadatasize 2048k results
       in pe_start of 3 MiB and mda_size of 3068 KiB.  Alternatively,
       --metadatasize 2044k results in pe_start at 2 MiB and mda_size of
       2044 KiB.

       The alignment of pe_start described above may be automatically
       overriden 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

       To use a different pe_start alignment, use the --dataalignment
       option.  The --metadatasize option would also typically be used in
       this case because the metadata area size also determines the location
       of pe_start.  When using these two options together, pe_start is
       calculated as: metadata 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 using these options.

       To shift an aligned pe_start value, use the --dataaligmentoffset
       option.  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         top

       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         top

       --bootloaderareasize Size[m|UNIT]
              Reserve space for the bootloader between the LVM metadata area
              and the first PE.  The bootloader area is reserved for
              bootloaders 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 bootloader 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 alignment, 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
              settings.  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
              number.  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

       --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.

              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
              LABEL_SCAN_SECTORS in the source). Use with care.

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

              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.

              Disable locking.

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

       --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 limitations on the ability to use vgsplit later.)

       -q|--quiet ...
              Suppress output and log messages. Overrides --debug and
              --verbose.  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
              extents will be in the same place and not be overwritten by
              new metadata. This provides a mechanism to upgrade the
              metadata format or to add/remove metadata areas. Use with

       --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.

              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
              unusual error messages in multi-stage operations if a tool
              relies on reading back metadata it believes has changed but

       -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
              vgcfgrestore(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
              detail of messages sent to stdout and stderr.

              Display version information.

              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         top

              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 extents (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):

              See the option description for information about the string

              Size is an input number that accepts an optional unit.  Input
              units are always treated as base two values, regardless of
              capitalization, e.g. 'k' and 'K' both refer to 1024.  The
              default input unit is specified by letter, followed by |UNIT.
              UNIT represents 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.)


       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         top

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

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

SEE ALSO         top

       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)
       vgconvert(8) vgdisplay(8) vgexport(8) vgextend(8) vgimport(8)
       vgimportclone(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)
       lvreduce(8) lvremove(8) lvrename(8) lvresize(8) lvs(8) lvscan(8)

       lvm-fullreport(8) lvm-lvpoll(8) lvm2-activation-generator(8)
       blkdeactivate(8) lvmdump(8)

       dmeventd(8) lvmpolld(8) lvmlockd(8) lvmlockctl(8) cmirrord(8)

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

COLOPHON         top

       This page is part of the lvm2 (Logical Volume Manager 2) project.
       Information about the project can be found at 
       ⟨http://www.sourceware.org/lvm2/⟩.  If you have a bug report for this
       manual page, see ⟨https://github.com/lvmteam/lvm2/issues⟩.  This page
       was obtained from the tarball
       https://github.com/lvmteam/lvm2/archive/v2_03_10.tar.gz fetched from
       ⟨https://github.com/lvmteam/lvm2/releases⟩ on 2020-08-13.  If you
       discover any rendering problems in this HTML version of the page, or
       you believe there is a better or more up-to-date source for the page,
       or you have corrections or improvements to the information in this
       COLOPHON (which is not part of the original manual page), send a mail
       to man-pages@man7.org

Red Hat, Inc.         LVM TOOLS 2.03.10(2) (2020-08-09)          PVCREATE(8)

Pages that refer to this page: fullreport(8)lvchange(8)lvconvert(8)lvcreate(8)lvdisplay(8)lvextend(8)lvm(8)lvm-config(8)lvmconfig(8)lvmdiskscan(8)lvm-dumpconfig(8)lvm-fullreport(8)lvm-lvpoll(8)lvpoll(8)lvreduce(8)lvremove(8)lvrename(8)lvresize(8)lvs(8)lvscan(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)vgconvert(8)vgcreate(8)vgdisplay(8)vgexport(8)vgextend(8)vgimport(8)vgimportclone(8)vgmerge(8)vgmknodes(8)vgreduce(8)vgremove(8)vgrename(8)vgs(8)vgscan(8)vgsplit(8)