tune2fs [ -l ] [ -c max-mount-counts ] [ -e errors-behavior ] [ -f ] [ -i interval-between-checks ] [ -I new_inode_size ] [ -j ] [ -J journal-options ] [ -m reserved-blocks-percentage ] [ -o [^]mount-options[,...] ] [ -p mmp_update_interval ] [ -r reserved-blocks-count ] [ -s sparse-super-flag ] [ -u user ] [ -g group ] [ -C mount-count ] [ -E extended-options ] [ -L volume-label ] [ -M last-mounted-directory ] [ -O [^]feature[,...] ] [ -Q quota-options ] [ -T time-last-checked ] [ -U UUID ] [ -z undo_file ] device
tune2fs allows the system administrator to adjust various tunable filesystem parameters on Linux ext2, ext3, or ext4 filesystems. The current values of these options can be displayed by using the -l option to tune2fs(8) program, or by using the dumpe2fs(8) program.
The device specifier can either be a filename (i.e., /dev/sda1), or a LABEL or UUID specifier: "LABEL=volume-label" or "UUID=uuid". (i.e., LABEL=home or UUID=e40486c6-84d5-4f2f-b99c-032281799c9d).
Staggering the mount-counts at which filesystems are forcibly checked will avoid all filesystems being checked at one time when using journaled filesystems.
You should strongly consider the consequences of disabling mount-count-dependent checking entirely. Bad disk drives, cables, memory, and kernel bugs could all corrupt a filesystem without marking the filesystem dirty or in error. If you are using journaling on your filesystem, your filesystem will never be marked dirty, so it will not normally be checked. A filesystem error detected by the kernel will still force an fsck on the next reboot, but it may already be too late to prevent data loss at that point.
See also the -i option for time-dependent checking.
WARNING: Removing an external journal from a filesystem which was not cleanly unmounted without first replaying the external journal can result in severe data loss and filesystem corruption.
It is strongly recommended that either -c (mount-count-dependent) or -i (time-dependent) checking be enabled to force periodic full e2fsck(8) checking of the filesystem. Failure to do so may lead to filesystem corruption (due to bad disks, cables, memory, or kernel bugs) going unnoticed, ultimately resulting in data loss or corruption.
WARNING: The undo file cannot be used to recover from a power or system crash.
We haven't found any bugs yet. That doesn't mean there aren't any...
tune2fs was written by Remy Card <Remy.Card@linux.org>. It is currently being maintained by Theodore Ts'o <firstname.lastname@example.org>. tune2fs uses the ext2fs library written by Theodore Ts'o <email@example.com>. This manual page was written by Christian Kuhtz <chk@data-hh.Hanse.DE>. Time-dependent checking was added by Uwe Ohse <firstname.lastname@example.org>.
tune2fs is part of the e2fsprogs package and is available from http://e2fsprogs.sourceforge.net.
debugfs(8), dumpe2fs(8), e2fsck(8), mke2fs(8), ext4(5)