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