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] [<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 67It tests SHA1 and general object sanity, and it does full tracking of 68the resulting reachability and everything else. It prints out any 69corruption it finds (missing or bad objects), and if you use the 70'--unreachable' flag it will also print out objects that exist but 71that aren't readable from any of the specified head nodes. 72 73So for example 74 75 git-fsck --unreachable HEAD $(cat .git/refs/heads/*) 76 77will do quite a _lot_ of verification on the tree. There are a few 78extra validity tests to be added (make sure that tree objects are 79sorted properly etc), but on the whole if "git-fsck" is happy, you 80do have a valid tree. 81 82Any corrupt objects you will have to find in backups or other archives 83(i.e., you can just remove them and do an "rsync" with some other site in 84the hopes that somebody else has the object you have corrupted). 85 86Of course, "valid tree" doesn't mean that it wasn't generated by some 87evil person, and the end result might be crap. git is a revision 88tracking system, not a quality assurance system ;) 89 90Extracted Diagnostics 91--------------------- 92 93expect dangling commits - potential heads - due to lack of head information:: 94 You haven't specified any nodes as heads so it won't be 95 possible to differentiate between un-parented commits and 96 root nodes. 97 98missing sha1 directory '<dir>':: 99 The directory holding the sha1 objects is missing. 100 101unreachable <type> <object>:: 102 The <type> object <object>, isn't actually referred to directly 103 or indirectly in any of the trees or commits seen. This can 104 mean that there's another root node that you're not specifying 105 or that the tree is corrupt. If you haven't missed a root node 106 then you might as well delete unreachable nodes since they 107 can't be used. 108 109missing <type> <object>:: 110 The <type> object <object>, is referred to but isn't present in 111 the database. 112 113dangling <type> <object>:: 114 The <type> object <object>, is present in the database but never 115 'directly' used. A dangling commit could be a root node. 116 117warning: git-fsck: tree <tree> has full pathnames in it:: 118 And it shouldn't... 119 120sha1 mismatch <object>:: 121 The database has an object who's sha1 doesn't match the 122 database value. 123 This indicates a serious data integrity problem. 124 125Environment Variables 126--------------------- 127 128GIT_OBJECT_DIRECTORY:: 129 used to specify the object database root (usually $GIT_DIR/objects) 130 131GIT_INDEX_FILE:: 132 used to specify the index file of the index 133 134GIT_ALTERNATE_OBJECT_DIRECTORIES:: 135 used to specify additional object database roots (usually unset) 136 137Author 138------ 139Written by Linus Torvalds <torvalds@osdl.org> 140 141Documentation 142-------------- 143Documentation by David Greaves, Junio C Hamano and the git-list <git@vger.kernel.org>. 144 145GIT 146--- 147Part of the gitlink:git[7] suite