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
           --driverloaded y|n
           --dump headers|metadata|metadata_all|metadata_search
        -f|--file 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 options).

       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 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.  (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 change.

       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

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 ]
           [    --driverloaded y|n ]
           [    --lockopt String ]
           [    --longhelp ]
           [    --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
              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.

       -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.

       --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.

       --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.

              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 description.

       --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

       -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

              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

       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 = 204800).
       pvck --labelsector 204800 /dev/sda

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)              PVCK(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)