82
If no filesystem type is specified,
84
will use the filesystem type
86
if the filesystem size is less than or equal to 3 megabytes.
87
If the filesystem size is greater than 3 but less than or equal to
90
will use the filesystem
94
will use the default filesystem type
96
82
.SH THE [defaults] STANZA
97
83
The following relations are defined in the
111
This relation, if set to a boolean value of true, forces
113
to always try to create an undo file, even if the undo file might be
114
huge and it might extend the time to create the filesystem image
115
because the inode table isn't being initialized lazily.
118
This relation specifies the default filesystem type if the user does not
123
is not started using a program name of the form
124
.BI mkfs. fs-type\fR.
125
If both the user and the
127
file does not specify a default filesystem type, mke2fs will use a
128
default filesystem type of
130
if a journal was requested via a command-line option, or
125
135
This relation specifies the default blocksize if the user does not
126
136
specify a blocksize on the command line, and the filesystem-type
137
147
specify one on the command line, and the filesystem-type
138
148
specific section of the configuration file does not specify a default
152
This relation specifies the directory where the undo file should be
153
stored. It can be overriden via the
154
.B E2FSPROGS_UNDO_DIR
155
environemnt variable. If the directory location is set to the value
158
will not create an undo file.
140
159
.SH THE [fs_types] STANZA
143
stanza names a filesystem type which can be specified via the
147
The value of the tag is a subsection where the relations in that
148
subsection define the defaults for that filesystem type. For
162
stanza names a filesystem type or usage type which can be specified via the
172
program constructs a list of fs_types by concatenating the filesystem
173
type (i.e., ext2, ext3, etc.) with the usage type list. For most
174
configuration options,
176
will look for a subsection in the
178
stanza corresponding with each entry in the constructed list, with later
179
entries overriding earlier filesystem or usage types.
181
example, consider the following
187
base_features = sparse_super,filetype,resize_inode,dir_index
201
features = has_journal
207
features = extents,flex_bg
223
features = ^resize_inode
231
If mke2fs started with a program name of
233
then the filesystem type of ext4 will be used. If the filesystem is
234
smaller than 3 megabytes, and no usage type is specified, then
239
This results in an fs_types list of "ext4, floppy". Both the ext4
240
subsection and the floppy subsection define an
242
relation, but since the later entries in the fs_types list supercede
243
earlier ones, the configuration parameter for fs_types.floppy.inode_size
244
will be used, so the filesystem will have an inode size of 128.
246
The exception to this resolution is the
248
tag, which is specifies a set of changes to the features used by the
249
filesystem, and which is cumulative. So in the above example, first
250
the configuration relation defaults.base_features would enable an
251
initial feature set with the sparse_super, filetype, resize_inode, and
252
dir_index features enabled. Then configuration relation
253
fs_types.ext4.features would enable the extents and flex_bg
254
features, and finally the configuration relation
255
fs_types.floppy.features would remove
256
the resize_inode feature, resulting in a filesystem feature set
257
consisting of the sparse_super, filetype, resize_inode, dir_index,
258
extents_and flex_bg features.
167
260
For each filesystem type, the following tags may be used in that
168
261
fs_type's subsection:
171
This relation specifies the features which are enabled for this
264
This relation specifies the features which are initially enabled for this
265
filesystem type. Only one
267
will be used, so if there are multiple entries in the fs_types list
268
whose subsections define the
270
relation, only the last will be used by
274
This relation specifies a comma-separated list of features edit
275
requests which modify the feature set
276
used by the newly constructed filesystem. The syntax is the same as the
278
command-line option to
280
that is, a feature can be prefixed by a caret ('^') symbol to disable
281
a named feature. Each
283
relation specified in the fs_types list will be applied in the order
284
found in the fs_types list.
174
286
.I default_features
175
287
This relation specifies set of features which should be enabled or
176
disabled to the features listed in the
288
disabled after applying the features listed in the
178
relation. It may be overridden by the
292
relations. It may be overridden by the
180
294
command-line option to
184
298
This relation specifies the default blocksize if the user does not
185
299
specify a blocksize on the command line.
302
This relation is a boolean which specifies whether the inode table should
303
be lazily initialized. It only has meaning if the uninit_bg feature is
304
enabled. If lazy_itable_init is true and the uninit_bg feature is
305
enabled, the inode table will
306
not fully initialized by
308
This speeds up filesystem
309
initialization noitceably, but it requires the kernel to finish
310
initializing the filesystem in the background when the filesystem is
188
314
This relation specifies the default inode ratio if the user does not
189
315
specify one on the command line.
192
318
This relation specifies the default inode size if the user does not
193
319
specify one on the command line.
322
This relation specifies the number of block goups that will be packed
323
together to create one large virtual block group on an ext4 filesystem.
324
This improves meta-data locality and performance on meta-data heavy
325
workloads. The number of goups must be a power of 2 and may only be
326
specified if the flex_bg filesystem feature is enabled.
328
This relation specifies additional extended options which should be
331
as if they were prepended to the argument of the
333
option. This can be used to configure the default extended options used
336
on a per-filesystem type basis.
196
339
.I /etc/mke2fs.conf
added
removed
misc/mke2fs.conf.5.in
