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] [--connectivity-only] [<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.

       --connectivity-only
           Check only the connectivity of tags, commits and tree objects. By avoiding to unpack
           blobs, this speeds up the operation, at the expense of missing corrupt objects or
           other problematic issues.

       --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