b2a32d57c8403d5f3a48938760c18b498fc32112
[git/git.git] / Documentation / git-fsck.txt
1 git-fsck(1)
2 ===========
3
4 NAME
5 ----
6 git-fsck - Verifies the connectivity and validity of the objects in the database
7
8
9 SYNOPSIS
10 --------
11 [verse]
12 'git fsck' [--tags] [--root] [--unreachable] [--cache] [--no-reflogs]
13 [--[no-]full] [--strict] [--verbose] [--lost-found]
14 [--[no-]dangling] [--[no-]progress] [--connectivity-only]
15 [--[no-]name-objects] [<object>*]
16
17 DESCRIPTION
18 -----------
19 Verifies the connectivity and validity of the objects in the database.
20
21 OPTIONS
22 -------
23 <object>::
24 An object to treat as the head of an unreachability trace.
25 +
26 If no objects are given, 'git fsck' defaults to using the
27 index file, all SHA-1 references in `refs` namespace, and all reflogs
28 (unless --no-reflogs is given) as heads.
29
30 --unreachable::
31 Print out objects that exist but that aren't reachable from any
32 of the reference nodes.
33
34 --[no-]dangling::
35 Print objects that exist but that are never 'directly' used (default).
36 `--no-dangling` can be used to omit this information from the output.
37
38 --root::
39 Report root nodes.
40
41 --tags::
42 Report tags.
43
44 --cache::
45 Consider any object recorded in the index also as a head node for
46 an unreachability trace.
47
48 --no-reflogs::
49 Do not consider commits that are referenced only by an
50 entry in a reflog to be reachable. This option is meant
51 only to search for commits that used to be in a ref, but
52 now aren't, but are still in that corresponding reflog.
53
54 --full::
55 Check not just objects in GIT_OBJECT_DIRECTORY
56 ($GIT_DIR/objects), but also the ones found in alternate
57 object pools listed in GIT_ALTERNATE_OBJECT_DIRECTORIES
58 or $GIT_DIR/objects/info/alternates,
59 and in packed Git archives found in $GIT_DIR/objects/pack
60 and corresponding pack subdirectories in alternate
61 object pools. This is now default; you can turn it off
62 with --no-full.
63
64 --connectivity-only::
65 Check only the connectivity of reachable objects, making sure
66 that any objects referenced by a reachable tag, commit, or tree
67 is present. This speeds up the operation by avoiding reading
68 blobs entirely (though it does still check that referenced blobs
69 exist). This will detect corruption in commits and trees, but
70 not do any semantic checks (e.g., for format errors). Corruption
71 in blob objects will not be detected at all.
72
73 --strict::
74 Enable more strict checking, namely to catch a file mode
75 recorded with g+w bit set, which was created by older
76 versions of Git. Existing repositories, including the
77 Linux kernel, Git itself, and sparse repository have old
78 objects that triggers this check, but it is recommended
79 to check new projects with this flag.
80
81 --verbose::
82 Be chatty.
83
84 --lost-found::
85 Write dangling objects into .git/lost-found/commit/ or
86 .git/lost-found/other/, depending on type. If the object is
87 a blob, the contents are written into the file, rather than
88 its object name.
89
90 --name-objects::
91 When displaying names of reachable objects, in addition to the
92 SHA-1 also display a name that describes *how* they are reachable,
93 compatible with linkgit:git-rev-parse[1], e.g.
94 `HEAD@{1234567890}~25^2:src/`.
95
96 --[no-]progress::
97 Progress status is reported on the standard error stream by
98 default when it is attached to a terminal, unless
99 --no-progress or --verbose is specified. --progress forces
100 progress status even if the standard error stream is not
101 directed to a terminal.
102
103 DISCUSSION
104 ----------
105
106 git-fsck tests SHA-1 and general object sanity, and it does full tracking
107 of the resulting reachability and everything else. It prints out any
108 corruption it finds (missing or bad objects), and if you use the
109 `--unreachable` flag it will also print out objects that exist but that
110 aren't reachable from any of the specified head nodes (or the default
111 set, as mentioned above).
112
113 Any corrupt objects you will have to find in backups or other archives
114 (i.e., you can just remove them and do an 'rsync' with some other site in
115 the hopes that somebody else has the object you have corrupted).
116
117 If core.commitGraph is true, the commit-graph file will also be inspected
118 using 'git commit-graph verify'. See linkgit:git-commit-graph[1].
119
120 Extracted Diagnostics
121 ---------------------
122
123 expect dangling commits - potential heads - due to lack of head information::
124 You haven't specified any nodes as heads so it won't be
125 possible to differentiate between un-parented commits and
126 root nodes.
127
128 missing sha1 directory '<dir>'::
129 The directory holding the sha1 objects is missing.
130
131 unreachable <type> <object>::
132 The <type> object <object>, isn't actually referred to directly
133 or indirectly in any of the trees or commits seen. This can
134 mean that there's another root node that you're not specifying
135 or that the tree is corrupt. If you haven't missed a root node
136 then you might as well delete unreachable nodes since they
137 can't be used.
138
139 missing <type> <object>::
140 The <type> object <object>, is referred to but isn't present in
141 the database.
142
143 dangling <type> <object>::
144 The <type> object <object>, is present in the database but never
145 'directly' used. A dangling commit could be a root node.
146
147 sha1 mismatch <object>::
148 The database has an object who's sha1 doesn't match the
149 database value.
150 This indicates a serious data integrity problem.
151
152 Environment Variables
153 ---------------------
154
155 GIT_OBJECT_DIRECTORY::
156 used to specify the object database root (usually $GIT_DIR/objects)
157
158 GIT_INDEX_FILE::
159 used to specify the index file of the index
160
161 GIT_ALTERNATE_OBJECT_DIRECTORIES::
162 used to specify additional object database roots (usually unset)
163
164 GIT
165 ---
166 Part of the linkgit:git[1] suite