man > pvck(8)

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

NAME
       pvck — Check metadata on physical volumes

SYNOPSIS
       pvck option_args position_args
           [ option_args ]

           --commandprofile String
           --config String
        -d|--debug
           --devices PV
           --devicesfile String
           --driverloaded y|n
           --dump headers|metadata|metadata_all|metadata_search
        -f|--file String
        -h|--help
           --journal String
           --labelsector Number
           --lockopt String
           --longhelp
           --nohints
           --nolocking
           --profile String
           --[pv]metadatacopies 0|1|2
        -q|--quiet
           --repair
           --repairtype pv_header|metadata|label_header
           --settings String
        -t|--test
        -v|--verbose
           --version
        -y|--yes

DESCRIPTION
       pvck checks and repairs LVM metadata on PVs.

   Dump options
       headers
       Print LVM on-disk headers and structures: label_header, pv_header, mda_header(s), and metada‐
       ta  text.   Warnings are printed if any values are incorrect.  The label_header and pv_header
       both exist in a 512 byte sector, usually the second sector of the device.  An mda_header  ex‐
       ists  in  a  512  byte sector at offset 4096 bytes.  A second mda_header can optionally exist
       near the end of the device.  The metadata text exists in an area (about 1MiB by default)  im‐
       mediately following the mda_header sector.  The metadata text is checked but not printed (see
       other options).

       metadata
       Print  the current LVM VG metadata text (or save to a file), using headers to locate the lat‐
       est copy of metadata.  If headers are  damaged,  metadata  may  not  be  found  (see  metada‐
       ta_search).  Use --settings "mda_num=2" to look in mda2 (the second mda at the end of the de‐
       vice, if used).  The metadata text is printed to stdout or saved to a file with --file.

       metadata_all
       List  all versions of VG metadata found in the metadata area, using headers to locate metada‐
       ta.  Full copies of all metadata are saved to a file with the --file option.  If headers  are
       damaged,  metadata  may  not  be  found (see metadata_search).  Use --settings "mda_num=2" as
       above.  Use -v to include descriptions and dates when listing metadata versions.

       metadata_search
       List all versions of VG metadata found in the metadata area, searching  common  locations  so
       metadata  can  be  found  if headers are damaged.  Full copies of all metadata are saved to a
       file with the --file option.  To save one specific version of metadata, use --settings "meta‐
       data_offset=<offset>", where the offset is taken from the list of versions found.  Use -v  to
       include descriptions and dates when listing metadata versions.

       metadata_area
       Save the entire text metadata area to a file without processing.

   Repair options
       --repair
       Repair  headers  and metadata on a PV.  This uses a metadata input file that was extracted by
       --dump, or a backup file (from /etc/lvm/backup).  When possible, use metadata saved by --dump
       from another PV in the same VG (or from a second metadata area on the PV).

       There are cases where the PV UUID needs to be specified for the PV  being  repaired.   It  is
       specified  using  --settings  "pv_uuid=<UUID>".  In particular, if the device name for the PV
       being repaired does not match the previous device name of the PV, then LVM may not be able to
       determine the correct PV UUID.  When headers are damaged on more than one PV in a VG,  it  is
       important for the user to determine the correct PV UUID and specify it in --settings.  Other‐
       wise,  the  wrong  PV UUID could be used if device names have been swapped since the metadata
       was last written.

       If a PV has no metadata areas and the pv_header is damaged, then the repair will not know  to
       create  no metadata areas during repair.  It will by default repair metadata in mda1.  To re‐
       pair with no metadata areas, use --settings "mda_offset=0 mda_size=0".

       There are cases where repair should be run on all PVs in the  VG  (using  the  same  metadata
       file):   if  all  PVs in the VG are damaged, if using an old metadata version, or if a backup
       file is used instead of raw metadata (taken from pvck dump.)

       Using --repair is equivalent to running --repairtype pv_header followed by --repairtype meta‐
       data.

       --repairtype pv_header
       Repairs the header sector, containing the pv_header and label_header.

       --repairtype metadata
       Repairs the mda_header and metadata text.  It requires the headers to be correct (having been
       undamaged or already repaired).

       --repairtype label_header
       Repairs label_header fields, leaving the pv_header (in the same sector) unchanged.   (repair‐
       type pv_header should usually be used instead.)

   Settings
       The --settings option controls or overrides certain dump or repair behaviors.  All offset and
       size  values in settings are in bytes (units are not recognized.)  These settings are subject
       to change.

       mda_num=1|2
       Select which metadata area should be used.  By default the first metadata area (1)  is  used.
       mda1  is always located at offset 4096.  mda2, at the end of the device, often does not exist
       (it's not created by default.) If mda1 is erased, mda2, if it exists, will often  still  have
       metadata.

       metadata_offset=bytes
       Select  metadata text at this offset.  Use with metadata_search to print/save one instance of
       metadata text.

       mda_offset=bytes mda_size=bytes
       Refers to a metadata area (mda) location and size.  An mda includes an mda_header and  circu‐
       lar metadata text buffer.  Setting this forces metadata_search look for metadata in the given
       area  instead of the standard locations.  When set to zero with repair, it indicates no meta‐
       data areas should exist.

       mda2_offset=bytes mda2_size=bytes
       When repairing a pv_header, this forces a specific offset and size for mda2  that  should  be
       recorded in the pv_header.

       pv_uuid=uuid
       Specify the PV UUID of the device being repaired.  When not specified, repair will attempt to
       determine the correct PV UUID by matching a device name in the metadata.

       device_size=bytes
       data_offset=bytes
       When  repairing  a pv_header, the device_size, data_offset, and pvid can all be specified di‐
       rectly, in which case these values are not taken from a metadata  file  (where  they  usually
       come  from),  and  the metadata file can be omitted.  data_offset is the starting location of
       the first physical extent (data), which follows the first metadata area.

USAGE
       Check for metadata on a device

       pvck PV ...
           [ COMMON_OPTIONS ]

       —

       Check and print LVM headers and metadata on a device

       pvck --dump headers|metadata|metadata_all|metadata_search PV
           [ -f|--file String ]
           [    --settings String ]
           [    --[pv]metadatacopies 0|1|2 ]
           [ COMMON_OPTIONS ]

       —

       Repair LVM headers or metadata on a device

       pvck --repairtype pv_header|metadata|label_header PV
           [ -f|--file String ]
           [    --settings String ]
           [ COMMON_OPTIONS ]

       —

       Repair LVM headers and metadata on a device

       pvck --repair -f|--file String PV
           [    --settings String ]
           [ COMMON_OPTIONS ]

       —

       Common options for command:
           [    --labelsector Number ]

       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


       --commandprofile String
              The command profile to use for command configuration.  See lvm.conf(5) for more infor‐
              mation 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.

       -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
              Restricts the devices that are visible and accessible to  the  command.   Devices  not
              listed will appear to be missing. This option can be repeated, or accepts a comma sep‐
              arated 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)  de‐
              vices/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 de‐
              bugging.

       --dump headers|metadata|metadata_all|metadata_search
              Dump headers and metadata from a PV for debugging and repair.  Option values  include:
              headers  to  print  and  check LVM headers, metadata to print or save the current text
              metadata, metadata_all to list or save all versions of  metadata,  metadata_search  to
              list or save all versions of metadata, searching standard locations in case of damaged
              headers, metadata_area to save an entire text metadata area to a file.

       -f|--file String
              Metadata file to read or write.

       -h|--help
              Display help text.

       --journal String
              Record  information in the systemd journal.  This information is in addition to infor‐
              mation 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 in‐
              clusive - 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 informa‐
              tion.

       --longhelp
              Display long help text.

       --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. Use with caution, concurrent commands may produce incorrect results.


       --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 al‐
              so suppress any prompts with answer 'no'.

       --repair
              Repair headers and metadata on a PV.

       --repairtype pv_header|metadata|label_header
              Repair headers and metadata on a PV. See command description.

       --settings String
              Specifies  command specific settings in "Key = Value" form.  Combine multiple settings
              in quotes, or repeat the settings option for each.

       -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 read‐
              ing back metadata it believes has changed but hasn't.

       -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.)

VARIABLES
       PV     Physical Volume name, a device path under /dev.  For commands  managing  physical  ex‐
              tents,  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
       If  the  partition  table  is corrupted or lost on /dev/sda, and you suspect there was an LVM
       partition at approximately 100 MiB, then this area of the disk can be scanned using the --la‐
       belsector parameter with a value of 204800 (100 * 1024 * 1024 / 512 = 204800).
       pvck --labelsector 204800 /dev/sda

SEE ALSO
       lvm(8), lvm.conf(5), lvmconfig(8), lvmdevices(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), vgimportdevices(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), blkdeactivate(8), lvmdump(8),

       dmeventd(8), lvmpolld(8), lvmlockd(8), lvmlockctl(8), cmirrord(8), lvmdbusd(8), fsadm(8),

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

Red Hat, Inc.                     LVM TOOLS 2.03.16(2) (2022-05-18)                          PVCK(8)