FSCK(8)                 OpenBSD System Manager's Manual                FSCK(8)

NAME
     fsck - file system consistency check and interactive repair

SYNOPSIS
     fsck [-dfnpvy] [-b block#] [-l maxparallel] [-T fstype:fsoptions]
          [-t fstype] [special | node ...]

DESCRIPTION
     The fsck command invokes file-system-specific programs to check the spe-
     cial devices listed in the fstab(5) file or on the command line for con-
     sistency.

     It is normally used in the script rc(8) during automatic reboot.  If no
     file systems are specified, fsck reads the file fstab(5) to determine
     which file systems to check and in what order.  Only partitions in fstab
     that are mounted ``rw'' or ``ro'' and that have non-zero pass numbers are
     checked.  File systems with pass number 1 (normally just the root file
     system) are checked one at a time.  When pass 1 completes, all remaining
     file systems are checked, with one process spawned per disk drive.  The
     disk drive containing each file system is inferred from the longest pre-
     fix of the device name that ends in a digit; the remaining characters are
     assumed to be the partition designator.  By default, file systems which
     are already mounted read/write are not checked.

     The options are as follows:

     -b block#
             Causes fsck to use the specified block as the location of the su-
             perblock.  Block 32 is usually an alternate super block.  This
             option is only valid for filesystems that support backup su-
             perblocks (ffs and ext2fs).

     -d      Debugging mode.  Just print the commands without executing them.
             Available only if fsck is compiled to support it.

     -f      Force checking of file systems, even when they are marked clean
             (for file systems that support this).

     -l maxparallel
             Limit the number of parallel checks to maxparallel.  By default,
             the limit is the number of disks, running one process per disk.
             If a smaller limit is given, the disks are checked round-robin,
             one file system at a time.

     -n      Assume a ``no'' response to all questions asked by fsck except
             for ``CONTINUE?'', which is assumed to be affirmative.  File sys-
             tems will not be opened for writing.  This is the default for
             file systems to be checked that are concurrently mounted
             writable.

     -p      Enter preen mode: fsck will check all file systems listed in
             fstab(5) according to their pass number, or any special devices
             listed on the command line, and will make minor repairs without
             human intervention.  Any major problems will cause fsck to exit
             with a non-zero exit code, so as to alert any invoking program or
             script that human intervention is required.

     -T fstype:fsoptions
             List of comma separated file system specific options for the
             specified file system type, in the same format as mount(8).

     -t fstype
             Invoke fsck only for the comma separated list of file system
             types.  If the list starts with ``no'', invoke fsck only in the
             file system types that are not specified in the list.

     -v      Print the commands before executing them.

     -y      Cause fsck to assume ``yes'' as the answer to all operator ques-
             tions.

     If neither of the -y or -n options are specified, the user may force fsck
     to assume an answer of ``yes'' to all the remaining questions by replying
     to a question with a value of ``F''.

FILES
     /etc/fstab  file system table

SEE ALSO
     fs(5), fstab(5), fsck_ext2fs(8), fsck_ffs(8), fsck_msdos(8), fsdb(8),
     growfs(8), mount(8), newfs(8), rc(8)

OpenBSD 4.7                      May 31, 2007                                2
