1 .\" Revision 1.0 93/06/3 23:00 chk
5 .TH TUNE2FS 8 "@E2FSPROGS_MONTH@ @E2FSPROGS_YEAR@" "E2fsprogs version @E2FSPROGS_VERSION@"
7 tune2fs \- adjust tunable filesystem parameters on second extended filesystems
23 .I interval-between-checks
34 .I reserved-blocks-percentage
38 .I reserved-blocks-count
62 .I last-mounted-directory
66 \fR[^]\fIfeature\fR[,...]
75 adjusts tunable filesystem parameters on a Linux second extended filesystem.
78 .BI \-c " max-mount-counts"
79 adjust the maximal mounts count between two filesystem checks. If
81 is -1 then the number of times the filesystem is mounted will be disregarded
82 by e2fsck and the kernel.
84 .BI \-e " error-behavior"
85 change the behavior of the kernel code when errors are detected.
87 can be one of the following:
89 \ continue\ \ Continue normal execution.
91 \ remount-ro\ Remount filesystem read-only.
93 \ panic\ \ Cause a kernel panic.
96 set the user group which can benefit from the reserved blocks.
99 can be a numerical gid or a group name. If a group name is given,
100 it is converted to a numerical gid before it is stored in the superblock.
102 .BI \-i " interval-between-checks\fR[\fBd\fR|\fBm\fR|\fBw\fR]"
103 adjust the maximal time between two filesystem checks.
110 in weeks. A value of zero will disable the timedependent checking.
113 Add an ext3 journal to the filesystem.
116 option is not specified, the default journal parameters will used will create
117 an appropriately sized journal (given the size of the filesystem)
118 stored within the filesystem.
120 .BR \-J " journal_options"
121 add a journal inode or device to the filesystem.
122 Journal options are comma
123 separated, and may take an argument using the equals ('=') sign.
124 Currently only two (mutually exclusive) options are supported,
129 .BI "\-J size=" journal-size
130 Create a journal stored in the filesystem of size
132 The size of the journal must be between 1MB and 100MB and there
133 must be sufficient free space in the filesystem to create a journal of
136 .BI "\-J device=" external-journal
137 Add an external journal found on a block device
142 journal must have been already created using the command
143 .B mke2fs -O journal_dev
147 list the contents of the filesystem superblock.
149 .BI \-m " reserved-blocks-percentage"
150 adjust the reserved blocks percentage on the given device.
152 .BI \-r " reserved-blocks-count"
153 adjust the reserved blocks count on the given device.
155 .BI \-s " sparse_super_flag"
156 set or reset the sparse_superblock flag. The sparse_superblock feature
157 saves space on really big filesystems.
159 The Linux 2.0 kernel does not properly support this feature. Neither do
160 all Linux 2.1 kernels; please don't use this unless you know what you're
164 set the user who can benefit from the reserved blocks.
166 can be a numerical uid or a user name. If a user name is given, it
167 is converted to a numerical uid before it is stored in the superblock.
169 .BI \-C " mount-count"
170 set the number of times the filesystem has been mounted.
172 .BI \-L " volume-label"
173 set the volume label of the filesystem.
174 Ext2 filesystem labels can be at most 16 characters long; if
176 is longer than 16 characters,
178 will truncate it and print a warning message.
180 .BI \-M " last-mounted-directory"
181 set the last-mounted directory for the filesystem.
183 .BI \-O " \fR[^]\fIfeature\fR[,...]"
184 set or clear the indicated filesystem features (options) in the filesystem.
186 can be one of the following supported filesystem options:
188 which will cause the filesystem to use sparse superblocks, and
190 which will cause the filesystem to store file type information in
191 directory entries. After setting or clearing either filesystem feature,
192 e2fsck must be run on the filesystem.
195 set the UUID of the filesystem. A sample UUID looks like this:
196 "c1b9d5a2-f162-11cf-9ece-0020afc76f16". The uuid may also be
198 which will set the filesystem UUID to the null UUID (clearing it),
200 which will generate a new random-based UUID for the filesystem, or
202 which will generate a new time-based UUID for the filesystem (see
205 We haven't found any bugs yet. That doesn't mean there aren't any...
207 Never use tune2fs to change parameters of a read/write mounted filesystem!
210 You're modifying a filesystem!
213 was written by Remy Card <Remy.Card@linux.org>.
215 uses the ext2fs library written by Theodore Ts'o <tytso@mit.edu>.
216 This manual page was written by Christian Kuhtz <chk@data-hh.Hanse.DE>.
217 Timedependent checking was added by Uwe Ohse <uwe@tirka.gun.de>.
220 is part of the e2fsprogs package and is available for anonymous
221 ftp from tsx-11.mit.edu in /pub/linux/packages/ext2fs.