GIT-FSCK(1)                                                        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] [<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 SHA1 references in .git/refs/*, and all reflogs
              (unless --no-reflogs is given) as heads.


       --unreachable
              Print out objects that exist but that aren&#8217;t reachable
              from any of the reference nodes.


       --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&#8217;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.


              It tests SHA1 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&#8217;t reachable from any of the
              specified head nodes.


              So for example

              git fsck --unreachable HEAD \
                      $(git for-each-ref --format="%(objectname)" refs/heads)


              will do quite a lot of verification on the tree. There are a few
              extra validity tests to be added (make sure that tree objects
              are sorted properly etc), but on the whole if git fsck is happy,
              you do have a valid tree.


              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).


              Of course, "valid tree" doesn&#8217;t mean that it wasn&#8217;t
              generated by some evil person, and the end result might be crap.
              git is a revision tracking system, not a quality assurance
              system ;)


EXTRACTED DIAGNOSTICS
       expect dangling commits - potential heads - due to lack of head
       information
              You haven&#8217;t specified any nodes as heads so it won&#8217;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&#8217;t actually referred to
              directly or indirectly in any of the trees or commits seen. This
              can mean that there&#8217;s another root node that you&#8217;re
              not specifying or that the tree is corrupt. If you haven&#8217;t
              missed a root node then you might as well delete unreachable
              nodes since they can&#8217;t be used.


       missing <type> <object>
              The <type> object <object>, is referred to but isn&#8217;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&#8217;s sha1 doesn&#8217;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-FSCK(1)
