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 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 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 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 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 questions.
- /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 required.
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).
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.