NAME

       git-fsck - Verifies the connectivity and validity of the objects in the database

SYNOPSIS

       git fsck [--tags] [--root] [--unreachable] [--cache] [--no-reflogs]
                [--[no-]full] [--strict] [--verbose] [--lost-found]
                [--[no-]dangling] [--[no-]progress] [<object>*]

DESCRIPTION

       Verifies the connectivity and validity of the objects in the database.

OPTIONS

       <object>
           An object to treat as the head of an unreachability trace.

           If no objects are given, git fsck defaults to using the index file, all SHA-1 references in refs
           namespace, and all reflogs (unless --no-reflogs is given) as heads.

       --unreachable
           Print out objects that exist but that aren’t reachable from any of the reference nodes.

       --[no-]dangling
           Print objects that exist but that are never directly used (default).  --no-dangling can be used to
           omit this information from the output.

       --root
           Report root nodes.

       --tags
           Report tags.

       --cache
           Consider any object recorded in the index also as a head node for an unreachability trace.

       --no-reflogs
           Do not consider commits that are referenced only by an entry in a reflog to be reachable. This option
           is meant only to search for commits that used to be in a ref, but now aren’t, but are still in that
           corresponding reflog.

       --full
           Check not just objects in GIT_OBJECT_DIRECTORY ($GIT_DIR/objects), but also the ones found in
           alternate object pools listed in GIT_ALTERNATE_OBJECT_DIRECTORIES or
           $GIT_DIR/objects/info/alternates, and in packed Git archives found in $GIT_DIR/objects/pack and
           corresponding pack subdirectories in alternate object pools. This is now default; you can turn it off
           with --no-full.

       --strict
           Enable more strict checking, namely to catch a file mode recorded with g+w bit set, which was created
           by older versions of Git. Existing repositories, including the Linux kernel, Git itself, and sparse
           repository have old objects that triggers this check, but it is recommended to check new projects
           with this flag.

       --verbose
           Be chatty.

       --lost-found
           Write dangling objects into .git/lost-found/commit/ or .git/lost-found/other/, depending on type. If
           the object is a blob, the contents are written into the file, rather than its object name.

       --[no-]progress
           Progress status is reported on the standard error stream by default when it is attached to a
           terminal, unless --no-progress or --verbose is specified. --progress forces progress status even if
           the standard error stream is not directed to a terminal.

DISCUSSION

       git-fsck tests SHA-1 and general object sanity, and it does full tracking of the resulting reachability
       and everything else. It prints out any corruption it finds (missing or bad objects), and if you use the
       --unreachable flag it will also print out objects that exist but that aren’t reachable from any of the
       specified head nodes (or the default set, as mentioned above).

       Any corrupt objects you will have to find in backups or other archives (i.e., you can just remove them
       and do an rsync with some other site in the hopes that somebody else has the object you have corrupted).

EXTRACTED DIAGNOSTICS

       expect dangling commits - potential heads - due to lack of head information
           You haven’t specified any nodes as heads so it won’t be possible to differentiate between un-parented
           commits and root nodes.

       missing sha1 directory <dir>
           The directory holding the sha1 objects is missing.

       unreachable <type> <object>
           The <type> object <object>, isn’t actually referred to directly or indirectly in any of the trees or
           commits seen. This can mean that there’s another root node that you’re not specifying or that the
           tree is corrupt. If you haven’t missed a root node then you might as well delete unreachable nodes
           since they can’t be used.

       missing <type> <object>
           The <type> object <object>, is referred to but isn’t present in the database.

       dangling <type> <object>
           The <type> object <object>, is present in the database but never directly used. A dangling commit
           could be a root node.

       sha1 mismatch <object>
           The database has an object who’s sha1 doesn’t match the database value. This indicates a serious data
           integrity problem.

ENVIRONMENT VARIABLES

       GIT_OBJECT_DIRECTORY
           used to specify the object database root (usually $GIT_DIR/objects)

       GIT_INDEX_FILE
           used to specify the index file of the index

       GIT_ALTERNATE_OBJECT_DIRECTORIES
           used to specify additional object database roots (usually unset)

GIT

       Part of the git(1) suite

Git 1.9.1                                          11/27/2018                                        GIT-FSCK(1)