git-fsck(1)

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]
            [--[no-]name-objects] [<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.

   --name-objects
       When displaying names of reachable objects, in addition to the
       SHA-1 also display a name that describes how they are reachable,
       compatible with git-rev-parse(1), e.g.
       HEAD@{1234567890}~25^2:src/.

   --[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

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