bup-fsck - verify or repair a bup repository
bup fsck [-r] [-g] [-v] [---quick] [-j jobs] [---par2-ok] [---disable-par2] [filenames...]
bup fsck is a tool for validating bup repositories in the same way that git fsck validates git repositories.
It can also generate and/or use "recovery blocks" using the par2(1) tool (if you have it installed). This allows you to recover from damaged blocks covering up to 5% of your .pack files.
In a normal backup system, damaged blocks are less important, because there tends to be enough data duplicated between backup sets that a single damaged backup set is non-critical. In a deduplicating backup system like bup, however, no block is ever stored more than once, even if it is used in every single backup. If that block were to be unrecoverable, all your backup sets would be damaged at once. Thus, it's important to be able to verify the integrity of your backups and recover from disk errors if they occur.
WARNING: bup fsck's recovery features are not available unless you have the free par2(1) package installed on your bup server.
WARNING: bup fsck obviously cannot recover from a complete disk failure. If your backups are important, you need to carefully consider redundancy (such as using RAID for multi-disk redundancy, or making off-site backups for site redundancy).
# generate recovery blocks for all packs that don't
# have them
bup fsck -g
# generate recovery blocks for a particular pack
bup fsck -g ~/.bup/objects/pack/153a1420cb1c8*.pack
# check all packs for correctness (can be very slow!)
# check all packs for correctness and recover any
# damaged ones
bup fsck -r
# check a particular pack for correctness and recover
# it if damaged
bup fsck -r ~/.bup/objects/pack/153a1420cb1c8*.pack
# check if recovery blocks are available on this system
if bup fsck --par2-ok; then
echo "par2 is ok"
bup-damage(1), fsck(1), git-fsck(1)
Part of the bup(1) suite.