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

     fsck -- file system consistency check and interactive repair

     fsck [-dfnPpqvy] [-l maxparallel] [-T fstype:fsoptions] [-t fstype]
          [-x mountpoint] [special | node ...]

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

     It is normally used in the script /etc/rc during automatic reboot.  If no
     file systems are specified, and ``preen'' mode is enabled ( -p option)
     fsck reads the table /etc/fstab to determine which file systems to check,
     in what order.  Only partitions in fstab that are mounted ``rw,'' ``rq''
     or ``ro'' and that have non-zero pass number 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, running one process per disk drive.  By default, file systems
     which are already mounted read-write are not checked.  The disk drive
     containing each file system is inferred from the longest prefix of the
     device name that ends in a digit; the remaining characters are assumed to
     be the partition designator.

     The options are as follows:

     -d      Debugging mode.  Just print the commands without executing them.

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

     -l maxparallel
             Limit the number of parallel checks to the number specified in
             the following argument.  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

     -n      Causes fsck to assume no as the answer to all operator questions,
             except "CONTINUE?".

     -P      Display a progress meter for each file system check.  This option
             also disables parallel checking.  Note that progress meters are
             not supported by all file system types.

     -p      Enter preen mode.  In preen mode, fsck will check all file sys-
             tems listed in /etc/fstab according to their pass number, and
             will make minor repairs without human intervention.

     -q      Quiet mode, do not output any messages for clean file systems.

     -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'' then invoke fsck for the
             file system types that are not specified in the list.

     -v      Print the commands before executing them.

     -x mountpoint
             Exclude the file system which has a mountpoint the same as in
             /etc/fstab.  Used only in ``preen'' mode.

     -y      Causes fsck to assume yes as the answer to all operator ques-

     /etc/fstab  file system table

     fsck exits with 0 on success.  Any major problems will cause fsck to exit
     with the following non-zero exit(3) codes, so as to alert any invoking
     program or script that human intervention is required.

     1     Usage problem.

     2     Unresolved errors while checking the file system.  Re-running fsck
           on the file system(s) is required.

     4     The root file system was changed in the process of checking, and
           updating the mount was unsuccessful.  A reboot (without sync) is

     8     The file system check has failed, and a subsequent check is
           required that will require human intervention.

     12    fsck exited because of the result of a signal (usually SIGINT or
           SIGQUIT from the terminal).

     fstab(5), fsck_ext2fs(8), fsck_ffs(8), fsck_lfs(8), fsck_msdos(8),

     A fsck utility appeared in 4.0BSD.  It was reimplemented as a file system
     independent wrapper in NetBSD 1.3.  The original file system specific
     utility became fsck_ffs(8) at this point.

NetBSD 7.0                    September 11, 2016                    NetBSD 7.0

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