# pvcreate

## 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
           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 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
           overridden 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_detection.
    
           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 --dataalignmentoffset
           option.  The pe_start alignment is calculated as described above,
           and then the value specified with --dataalignmentoffset 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_ ]
               [    **--devices** _PV_ ]
               [    **--devicesfile** _String_ ]
               [    **--driverloaded y** |**n**]
               [    **--journal** _String_ ]
               [    **--lockopt** _String_ ]
               [    **--longhelp**]
               [    **--nohints**]
               [    **--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
                  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(5)
                  settings.   The  String  arg  uses  the  same   format   as
                  lvm.conf(5),   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
                  configured).
    
           **--devices** _PV_
                  Devices  that  the  command  can  use.  This  option can be
                  repeated or accepts a comma separated list of devices. This
                  overrides the devices file.
    
           **--devicesfile** _String_
                  A file listing devices that LVM should use.  The file  must
                  exist   in   _/etc/lvm/devices/_  and  is  managed  with  the
                  lvmdevices(8)  command.   This  overrides  the  lvm.conf(5)
                  **devices/devicesfile** and **devices/use_devicesfile** settings.
    
           **--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.
    
           **--journal** _String_
                  Record   information   in   the   systemd   journal.   This
                  information is in addition to information  enabled  by  the
                  lvm.conf  log/journal setting.  command: record information
                  about the command.   output:  record  the  default  command
                  output.  debug: record full command debugging.
    
           **--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.
    
           **--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.
    
           **--nohints**
                  Do  not  use  the  hints  file to locate devices for PVs. A
                  command may read more devices to find PVs  when  hints  are
                  not used. The command will still perform standard hint file
                  invalidation where appropriate.
    
           **--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 provided.
    
           **--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(5).  **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 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  unusual  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 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.
    
           **--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 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): _PV_[**:**_PE_**+**_PE_]...
    
           _String_ See the option description for information about the string
                  content.
    
           _Size_[UNIT]
                  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: **b** |**B** is bytes, **s** |**S** is sectors of 512 bytes, **k** |**K** is
                  KiB, **m** |**M** is MiB, **g** |**G** is GiB, **t** |**T** is TiB, **p** |**P** is PiB, **e** |**E** is
                  EiB.  (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 4 KiB sector drive that compensates for windows
           partitioning (sector 7 is the lowest aligned logical block, the
           4 KiB sectors start at LBA -1, and consequently sector 63 is
           aligned on a 4 KiB boundary) manually account for this when
           initializing for use by LVM.
           **pvcreate --dataalignmentoffset 7s /dev/sdb**
    


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