TUNE2FS(8)

NAME
       tune2fs  -  adjust tunable filesystem parameters on second
       extended filesystems

SYNOPSIS
       tune2fs [ -l ] [ -c max-mount-counts ] [ -e  errors-behav-
       ior ] [ -i interval-between-checks ] [ -m reserved-blocks-
       percentage ] [ -r reserved-blocks-count  ]  [  -s  sparse-
       super-flag ] [ -u user ] [ -g group ] [ -C mount-count ] [
       -L volume-name ] [ -M last-mounted-directory ] [ -U UUID ]
       device

DESCRIPTION
       tune2fs  adjusts  tunable filesystem parameters on a Linux
       second extended filesystem.

       Never use tune2fs on a read/write  mounted  filesystem  to
       change parameters!

OPTIONS
       -c max-mount-counts
              adjust   the   maximal  mounts  count  between  two
              filesystem checks.

       -e errors-behavior
              change the behavior of the kernel code when  errors
              are  detected.   errors-behavior  can be one of the
              followings:
                   continue       Continue normal execution.
                   remount-ro     Remount  the  filesystem  read-
              only.
                   panic          Causes a kernel panic.

       -g group
              set  the  user  group  which  can  benefit from the
              reserved blocks.
              group can be a numerical gid or a group name.

       -i interval-between-checks[d|m|w]
              adjust the  maximal  time  between  two  filesystem
              checks.   No  postfix or `d' result in days, `m' in
              months, and `w' in weeks.  A  value  of  zero  will
              disable the timedependent checking.

       -l     list the contents of the filesystem superblock.

       -m reserved-blocks-percentage
              adjust  the reserved blocks percentage on the given
              device.

       -r reserved-blocks-count
              adjust the  reserved  blocks  count  on  the  given
              device.

       -s sparse_super_flag
              sets  and  resets  the sparse_superblock flag.  The
              sparse_superblock feature saves space on really big
              filesystems.   Warning:  The  Linux 2.0 kernel does
              not properly support this feature.  Neither do  all
              Linux 2.1 kernels; please don't use this unless you
              know what you're doing!

       -u user
              set the user who  can  benefit  from  the  reserved
              blocks.   user  can  be  a  numerical uid or a user
              name.
              -C mount-count set the number of times the filesys-
              tem has been mounted.

       -L volume-label
              set the volume label of the filesystem.

       -M last-mounted-directory
              set the last-mounted direcctory for the filesystem.

       -U UUID
              set the UUID of  the  filesystem.   A  sample  UUID
              looks                   like                  this:
              "c1b9d5a2-f162-11cf-9ece-0020afc76f16".   The  uuid
              may  also  be "null", which will set the filesystem
              UUID to the null UUID.  The uuid may also be  "ran-
              dom", which will generate a new random UUID for the
              filesystem.

BUGS
       We didn't find any bugs yet. Perhaps there  are  bugs  but
       it's unlikely.

WARNING
       Use  this  utility  on  your  own  risk.  You're modifying
       filesystems.

AUTHOR
       tune2fs has been written by Remy Card  lt;card@masi.ibp.fr,
       the developer and maintainer of the ext2 fs.
       tune2fs  uses  the ext2fs library written by Theodore Ts'o
       lt;tytso@mit.edu.
       This manual page was written by Christian Kuhtz <chk@data-
       hh.Hanse.DE>.
       Timedependent    checking    was   added   by   Uwe   Ohse
       lt;uwe@tirka.gun.de.

AVAILABILITY
       tune2fs is available for anonymous ftp from ftp.ibp.fr and
       tsx-11.mit.edu in /pub/linux/packages/ext2fs.

SEE ALSO
       dumpe2fs(8) e2fsck(8) mke2fs(8)