FSCK(8) BSD System Manager's Manual FSCK(8)
NAME
fsck -- file system consistency check and interactive repair
SYNOPSIS
fsck [-dfnPpqvy] [-l maxparallel] [-T fstype:fsoptions] [-t fstype] [-x mountpoint] [special | node ...]
DESCRIPTION
The fsck command invokes file system-specific programs to check the special devices listed in the fstab(5) file or in the command line for
consistency.
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 sys-
tem) 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 read-
write.
-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 time.
-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 systems 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 filesystems.
-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 filesystem 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 questions.
FILES
/etc/fstab file system table
EXIT STATUS
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 filesystem. Re-running fsck on the filesystem(s) is required.
4 The root filesystem was changed in the process of checking, and updating the mount was unsuccessful. A reboot (without sync) is
required.
8 The filesystem 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).
SEE ALSO
fstab(5), fsck_ext2fs(8), fsck_ffs(8), fsck_lfs(8), fsck_msdos(8), mount(8)
BSD
February 17, 2010 BSD