1git-fsck(1) 2=========== 3 4NAME 5---- 6git-fsck - Verifies the connectivity and validity of the objects in the database 7 8 9SYNOPSIS 10-------- 11[verse] 12'git fsck' [--tags] [--root] [--unreachable] [--cache] [--no-reflogs] 13 [--[no-]full] [--strict] [--verbose] [--lost-found] 14 [--[no-]progress] [<object>*] 15 16DESCRIPTION 17----------- 18Verifies the connectivity and validity of the objects in the database. 19 20OPTIONS 21------- 22<object>:: 23 An object to treat as the head of an unreachability trace. 24+ 25If no objects are given, 'git fsck' defaults to using the 26index file, all SHA1 references in .git/refs/*, and all reflogs (unless 27--no-reflogs is given) as heads. 28 29--unreachable:: 30 Print out objects that exist but that aren't reachable from any 31 of the reference nodes. 32 33--root:: 34 Report root nodes. 35 36--tags:: 37 Report tags. 38 39--cache:: 40 Consider any object recorded in the index also as a head node for 41 an unreachability trace. 42 43--no-reflogs:: 44 Do not consider commits that are referenced only by an 45 entry in a reflog to be reachable. This option is meant 46 only to search for commits that used to be in a ref, but 47 now aren't, but are still in that corresponding reflog. 48 49--full:: 50 Check not just objects in GIT_OBJECT_DIRECTORY 51 ($GIT_DIR/objects), but also the ones found in alternate 52 object pools listed in GIT_ALTERNATE_OBJECT_DIRECTORIES 53 or $GIT_DIR/objects/info/alternates, 54 and in packed git archives found in $GIT_DIR/objects/pack 55 and corresponding pack subdirectories in alternate 56 object pools. This is now default; you can turn it off 57 with --no-full. 58 59--strict:: 60 Enable more strict checking, namely to catch a file mode 61 recorded with g+w bit set, which was created by older 62 versions of git. Existing repositories, including the 63 Linux kernel, git itself, and sparse repository have old 64 objects that triggers this check, but it is recommended 65 to check new projects with this flag. 66 67--verbose:: 68 Be chatty. 69 70--lost-found:: 71 Write dangling objects into .git/lost-found/commit/ or 72 .git/lost-found/other/, depending on type. If the object is 73 a blob, the contents are written into the file, rather than 74 its object name. 75 76--progress:: 77--no-progress:: 78 Progress status is reported on the standard error stream by 79 default when it is attached to a terminal, unless 80 --no-progress or --verbose is specified. --progress forces 81 progress status even if the standard error stream is not 82 directed to a terminal. 83 84It tests SHA1 and general object sanity, and it does full tracking of 85the resulting reachability and everything else. It prints out any 86corruption it finds (missing or bad objects), and if you use the 87'--unreachable' flag it will also print out objects that exist but 88that aren't reachable from any of the specified head nodes. 89 90So for example 91 92 git fsck --unreachable HEAD \ 93 $(git for-each-ref --format="%(objectname)" refs/heads) 94 95will do quite a _lot_ of verification on the tree. There are a few 96extra validity tests to be added (make sure that tree objects are 97sorted properly etc), but on the whole if 'git fsck' is happy, you 98do have a valid tree. 99 100Any corrupt objects you will have to find in backups or other archives 101(i.e., you can just remove them and do an 'rsync' with some other site in 102the hopes that somebody else has the object you have corrupted). 103 104Of course, "valid tree" doesn't mean that it wasn't generated by some 105evil person, and the end result might be crap. git is a revision 106tracking system, not a quality assurance system ;) 107 108Extracted Diagnostics 109--------------------- 110 111expect dangling commits - potential heads - due to lack of head information:: 112 You haven't specified any nodes as heads so it won't be 113 possible to differentiate between un-parented commits and 114 root nodes. 115 116missing sha1 directory '<dir>':: 117 The directory holding the sha1 objects is missing. 118 119unreachable <type> <object>:: 120 The <type> object <object>, isn't actually referred to directly 121 or indirectly in any of the trees or commits seen. This can 122 mean that there's another root node that you're not specifying 123 or that the tree is corrupt. If you haven't missed a root node 124 then you might as well delete unreachable nodes since they 125 can't be used. 126 127missing <type> <object>:: 128 The <type> object <object>, is referred to but isn't present in 129 the database. 130 131dangling <type> <object>:: 132 The <type> object <object>, is present in the database but never 133 'directly' used. A dangling commit could be a root node. 134 135sha1 mismatch <object>:: 136 The database has an object who's sha1 doesn't match the 137 database value. 138 This indicates a serious data integrity problem. 139 140Environment Variables 141--------------------- 142 143GIT_OBJECT_DIRECTORY:: 144 used to specify the object database root (usually $GIT_DIR/objects) 145 146GIT_INDEX_FILE:: 147 used to specify the index file of the index 148 149GIT_ALTERNATE_OBJECT_DIRECTORIES:: 150 used to specify additional object database roots (usually unset) 151 152GIT 153--- 154Part of the linkgit:git[1] suite