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 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.
Repairs the header sector, containing the pv_header and label_header.
Repairs the mda_header and metadata text. It requires the headers to be correct (having been undamaged or already repaired).
Repairs label_header fields, leaving the pv_header (in the same sector) unchanged. (repairtype pv_header should usually be used instead.)
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.
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.
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.
pvck PV ...
Check and print LVM headers and metadata on a device
pvck --dump headers|metadata|metadata_all|metadata_search PV
Repair LVM headers or metadata on a device
pvck --repairtype pv_header|metadata|label_header PV
Repair LVM headers and metadata on a device
pvck --repair -f|--file String PV
Common options for command:
Common options for lvm:
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
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)