1BTRFS-INSPECT-INTE(8)            Btrfs Manual            BTRFS-INSPECT-INTE(8)
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NAME

6       btrfs-inspect-internal - query various internal information
7

SYNOPSIS

9       btrfs inspect-internal <subcommand> <args>
10

DESCRIPTION

12       This command group provides an interface to query internal information.
13       The functionality ranges from a simple UI to an ioctl or a more complex
14       query that assembles the result from several internal structures. The
15       latter usually requires calls to privileged ioctls.
16

SUBCOMMAND

18       dump-super [options] <device> [device...]
19           (replaces the standalone tool btrfs-show-super)
20
21           Show btrfs superblock information stored on given devices in
22           textual form. By default the first superblock is printed, more
23           details about all copies or additional backup data can be printed.
24
25           Besides verification of the filesystem signature, there are no
26           other sanity checks. The superblock checksum status is reported,
27           the device item and filesystem UUIDs are checked and reported.
28
29               Note
30               the meaning of option -s has changed in version 4.8 to be
31               consistent with other tools to specify superblock copy rather
32               the offset. The old way still works, but prints a warning.
33               Please update your scripts to use --bytenr instead. The option
34               -i has been deprecated.
35           Options
36
37           -f|--full
38               print full superblock information, including the system chunk
39               array and backup roots
40
41           -a|--all
42               print information about all present superblock copies (cannot
43               be used together with -s option)
44
45           -i <super>
46               (deprecated since 4.8, same behaviour as --super)
47
48           --bytenr <bytenr>
49               specify offset to a superblock in a non-standard location at
50               bytenr, useful for debugging (disables the -f option)
51
52               If there are multiple options specified, only the last one
53               applies.
54
55           -F|--force
56               attempt to print the superblock even if a valid BTRFS signature
57               is not found; the result may be completely wrong if the data
58               does not resemble a superblock
59
60           -s|--super <bytenr>
61               (see compatibility note above)
62
63               specify which mirror to print, valid values are 0, 1 and 2 and
64               the superblock must be present on the device with a valid
65               signature, can be used together with --force
66
67       dump-tree [options] <device>
68           (replaces the standalone tool btrfs-debug-tree)
69
70           Dump tree structures from a given device in textual form, expand
71           keys to human readable equivalents where possible. This is useful
72           for analyzing filesystem state or inconsistencies and has a
73           positive educational effect on understanding the internal
74           filesystem structure.
75
76               Note
77               contains file names, consider that if you’re asked to send the
78               dump for analysis. Does not contain file data.
79           Options
80
81           -e|--extents
82               print only extent-related information: extent and device trees
83
84           -d|--device
85               print only device-related information: tree root, chunk and
86               device trees
87
88           -r|--roots
89               print only short root node information, ie. the root tree keys
90
91           -R|--backups
92               same as --roots plus print backup root info, ie. the backup
93               root keys and the respective tree root block offset
94
95           -u|--uuid
96               print only the uuid tree information, empty output if the tree
97               does not exist
98
99           -b <block_num>
100               print info of the specified block only, can be specified
101               multiple times
102
103           --follow
104               use with -b, print all children tree blocks of <block_num>
105
106           --dfs
107               use depth-first search to print trees. (default) the nodes and
108               leaves are intermixed in the output
109
110           --bfs
111               use breadth-first search to print trees. the nodes are printed
112               before all leaves
113
114           -t <tree_id>
115               print only the tree with the specified ID, where the ID can be
116               numerical or common name in a flexible human readable form
117
118               The tree id name recognition rules:
119
120               ·   case does not matter
121
122               ·   the C source definition, eg. BTRFS_ROOT_TREE_OBJECTID
123
124               ·   short forms without BTRFS_ prefix, without _TREE and
125                   _OBJECTID suffix, eg. ROOT_TREE, ROOT
126
127               ·   convenience aliases, eg. DEVICE for the DEV tree, CHECKSUM
128                   for CSUM
129
130               ·   unrecognized ID is an error
131
132       inode-resolve [-v] <ino> <path>
133           (needs root privileges)
134
135           resolve paths to all files with given inode number ino in a given
136           subvolume at path, ie. all hardlinks
137
138           Options
139
140           -v
141               verbose mode, print count of returned paths and ioctl() return
142               value
143
144       logical-resolve [-Pv] [-s <bufsize>] <logical> <path>
145           (needs root privileges)
146
147           resolve paths to all files at given logical address in the linear
148           filesystem space
149
150           Options
151
152           -P
153               skip the path resolving and print the inodes instead
154
155           -v
156               verbose mode, print count of returned paths and all ioctl()
157               return values
158
159           -s <bufsize>
160               set internal buffer for storing the file names to bufsize,
161               default is 4096, maximum 64k
162
163       min-dev-size [options] <path>
164           (needs root privileges)
165
166           return the minimum size the device can be shrunk to, without
167           performing any resize operation, this may be useful before
168           executing the actual resize operation
169
170           Options
171
172           --id <id>
173               specify the device id to query, default is 1 if this option is
174               not used
175
176       rootid <path>
177           for a given file or directory, return the containing tree root id,
178           but for a subvolume itself return its own tree id (ie. subvol id)
179
180               Note
181               The result is undefined for the so-called empty subvolumes
182               (identified by inode number 2), but such a subvolume does not
183               contain any files anyway
184
185       subvolid-resolve <subvolid> <path>
186           (needs root privileges)
187
188           resolve the absolute path of the subvolume id subvolid
189
190       tree-stats [options] <device>
191           (needs root privileges)
192
193           Print sizes and statistics of trees.
194
195           Options
196
197           -b
198               Print raw numbers in bytes.
199

EXIT STATUS

201       btrfs inspect-internal returns a zero exit status if it succeeds. Non
202       zero is returned in case of failure.
203

AVAILABILITY

205       btrfs is part of btrfs-progs. Please refer to the btrfs wiki
206       http://btrfs.wiki.kernel.org for further details.
207

SEE ALSO

209       mkfs.btrfs(8)
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213Btrfs v5.1                        05/17/2019             BTRFS-INSPECT-INTE(8)
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