pvck(8) — Linux manual page


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

NAME         top

       pvck — Check metadata on physical volumes

SYNOPSIS         top

       pvck option_args position_args
           [ option_args ]

           --commandprofile String
           --config String
           --devices PV
           --devicesfile String
           --driverloaded y|n
           --dump headers|metadata|metadata_all|metadata_search
        -f|--file String
           --journal String
           --labelsector Number
           --lockopt String
           --profile String
           --[pv]metadatacopies 0|1|2
           --repairtype pv_header|metadata|label_header
           --settings String

DESCRIPTION         top

       pvck checks and repairs LVM metadata on PVs.

   Dump options
       Print LVM on-disk headers and structures: label_header,
       pv_header, mda_header(s), and metadata 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 exists 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) immediately following the mda_header
       sector.  The metadata text is checked but not printed (see other

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

       List all versions of VG metadata found in the metadata area,
       using headers to locate metadata.  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.

       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 "metadata_offset=<offset>", where the
       offset is taken from the list of versions found.  Use -v to
       include descriptions and dates when listing metadata versions.

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

   Repair options
       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.  Otherwise, 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 repair
       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 metadata.

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

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

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

       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

       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.

       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 circular 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 metadata 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.

       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.

       When repairing a pv_header, the device_size, data_offset, and
       pvid can all be specified directly, 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         top

       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         top

       --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.

       -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

       --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.

       --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.

              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.

              Display long help text.

              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.

              Disable locking.

       --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'.

              Repair headers and metadata on a PV.

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

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

              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.

       -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.)

VARIABLES         top

       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 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


       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

       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 --labelsector
       parameter with a value of 204800 (100 * 1024 * 1024 / 512 =
       pvck --labelsector 204800 /dev/sda

SEE ALSO         top

       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), lvmcache(7), lvmraid(7),
       lvmthin(7), lvmvdo(7), lvmautoactivation(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 project's upstream Git repository
       ⟨git://sourceware.org/git/lvm2.git⟩ on 2023-12-22.  (At that
       time, the date of the most recent commit that was found in the
       repository was 2023-12-06.)  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

Red Hat, Inc.     LVM TOOLS 2.03.24(2)-git (2023-11-21)          PVCK(8)

Pages that refer to this page: lvchange(8)lvconvert(8)lvcreate(8)lvdisplay(8)lvextend(8)lvm(8)lvmconfig(8)lvmdevices(8)lvmdiskscan(8)lvm-fullreport(8)lvm-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)vgimportdevices(8)vgmerge(8)vgmknodes(8)vgreduce(8)vgremove(8)vgrename(8)vgs(8)vgscan(8)vgsplit(8)