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Diffstat (limited to 'man/pvck.8_des')
| -rw-r--r-- | man/pvck.8_des | 87 |
1 files changed, 81 insertions, 6 deletions
diff --git a/man/pvck.8_des b/man/pvck.8_des index fb826d30e..2169d730f 100644 --- a/man/pvck.8_des +++ b/man/pvck.8_des @@ -1,8 +1,83 @@ -pvck checks LVM metadata on PVs. +pvck checks and repairs LVM metadata on PVs. -Use the --dump option to extract metadata from PVs for debugging. -With dump, set --pvmetadatacopies 2 to extract metadata from a -second metadata area at the end of the device. Use the --file -option to save the raw metadata to a specified file. (The raw -metadata is not usable with vgcfgbackup and vgcfgrestore.) +.SS Dump + +.B headers +.br +Print header values and warn if any values are incorrect. Checks the +label_header, pv_header, mda_header(s), and metadata text. + +.B metadata +.br +Print or save the current metadata text, using headers to locate the +metadata. If headers are damaged, the metadata may not be found. 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. With --file, +the metadata text is saved to a file. + +.B metadata_all +.br +List or save all versions of metadata found in the metadata area, using +headers to locate the metadata. If headers are damaged, the metadata may +not be found. Use --settings "mda_num=2" as above. All metadata versions +are listed (add -v to include descriptions and dates in the listing.) +With -file, all versions are written to a file. + +.B metadata_search +.br +Search for all versions of metadata in the common locations. This does +not use headers, so it can find metadata even when headers are damaged. +Use --settings "mda_num=2" as above. All metadata versions are listed +(add -v to include descriptions and dates in the listing.) With --file, +all versions are written to a file. To save one copy of metadata, use +--settings "metadata_offset=<offset>", where the offset is taken from the +dump listing. + +.B metadata_area +.br +Save the entire text metadata area to a file without processing. + +.SS Repair + +.B --repair +.br +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 had 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. + +Using --repair is equivalent to running --repairtype pv_header followed by +--repairtype metadata. + +.B --repairtype pv_header +.br +Repairs the header sector, containing the pv_header and label_header. + +.B --repairtype metadata +.br +Repairs the mda_header and metadata text. It requires the headers to be +correct (having been undamaged or already repaired). + +.B --repairtype label_header +.br +Repairs label_header fields, leaving the pv_header (in the same sector) +unchanged. (repairtype pv_header should usually be used instead.) |