fsck, fsck1 - perform file system consistency check
fsck [-aclmrs] [device] ...
-a Automatically repair inconsistencies
-c Check and list only the specified i-nodes
-l List the files and directories in the filesytem
-r Prompt user for repairs if inconsistencies are found
-s List the superblock of the file system
fsck /dev/hd4 # Check file system on /dev/hd4
fsck -a /dev/at0 # Automatically fix errors on /dev/at0
fsck -l /dev/fd0 # List the contents of /dev/fd0
fsck -c 2 3 /dev/hd3
# Check and list /dev/hd3 i-nodes 2 & 3
Fsck performs consistency checks on the file systems which reside on the
specified devices. Fsck1 is an alternate version for use on obsolete V1
file systems. When either the -a or -r flags are given, the file system
will be repaired if errors are found. Before running fsck on a mounted
file system, it must first be unmounted. Trying to repair a mounted file
system is dangerous and should not be attempted.
To repair the root file system (which cannot be unmounted), first type
CTRL-F9 at the console to kill any and all processes. Log back in as
root, type sync to force any buffered changes to disk, run fsck on the
root file system and immediately reboot the computer by typing reboot.
It is necessary to kill all processes before repairing the root file
system to prevent them from modifying any disk blocks while fsck is
running. This is only necessary for the root file system, any other file
system can simply be unmounted before it is checked.