fsck(1M) UNIX System V(s5) fsck(1M)
NAME
fsck (s5) - check and repair s5 file systems
SYNOPSIS
fsck [-F s5] [generic_options] [special...]
fsck [-F s5] [generic_options] [-y] [-n] [-p] [-sX] [-SX] [-tfile] [-l]
[-q] [-D] [-f] [special...]
DESCRIPTION
generic_options are options supported by the generic fsck command.
The options are:
-F s5 Specifies the s5-FSType.
-y Assume a yes response to all questions asked by fsck.
-n Assume a no response to all questions asked by fsck; do not
open the file system for writing.
-p Correct inconsistencies that can be fixed automatically, that
is, inconsistencies that are deemed harmless and can be fixed
without confirmation by the administrator. Examples of such
inconsistencies are unreferenced i-nodes, incorrect counts in
the superblocks, and missing blocks in the free list.
-sX Ignore the actual free list and (unconditionally) reconstruct a
new one by rewriting the super-block of the file system. The
file system should be unmounted while this is done; if this is
not possible, care should be taken that the system is quiescent
and that it is rebooted immediately afterwards. This
precaution is necessary so that the old, bad, in-core copy of
the superblock will not continue to be used, or written on the
file system.
The -sX suboption allows for creating an optimal free-list
organization.
If X is not given, the values used when the file system was
created are used. The format of X is cylinder size:gap size.
-SX Conditionally reconstruct the free list. This suboption is like
-sX above except that the free list is rebuilt only if there
were no discrepancies discovered in the file system. Using S
will force a no response to all questions asked by fsck. This
suboption is useful for forcing free list reorganization on
uncontaminated file systems.
-tfile If fsck cannot obtain enough memory to keep its tables, it uses
a scratch file. If the t option is specified, the file named is
used as the scratch file, if needed. Without the t option,
fsck will prompt the user for the name of the scratch file. The
file chosen should not be on the file system being checked, and
if it is not a special file or did not already exist, it is
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fsck(1M) UNIX System V(s5) fsck(1M)
removed when fsck completes.
-l Identify damaged files by their logical names.
-q Quiet fsck. Unreferenced fifos will silently be removed. If
fsck requires it, counts in the superblock will be
automatically fixed and the free list salvaged.
-D Directories are checked for bad blocks. Useful after system
crashes.
-f Fast check. Check block and sizes and check the free list.
The free list will be reconstructed if it is necessary.
Inconsistencies checked are as follows:
1. Blocks claimed by more than one i-node or the free list.
2. Blocks claimed by an i-node or the free list outside the
range of the file system.
3. Incorrect link counts.
4. Size checks:
Incorrect number of blocks.
Directory size not 16-byte aligned.
5. Bad i-node format.
6. Blocks not accounted for anywhere.
7. Directory checks:
File pointing to unallocated i-node.
I-node number out of range.
8. Super Block checks:
More than 65536 i-nodes.
More blocks for i-nodes than there are in the file
system.
9. Bad free block list format.
10. Total free block and/or free i-node count incorrect.
Orphaned files and directories (allocated but unreferenced) are, with the
user's concurrence, reconnected by placing them in the lost+found
directory, if the files are nonempty. The user will be notified if the
file or directory is empty or not. Empty files or directories are
removed, as long as the n suboption is not specified. fsck will force
the reconnection of nonempty directories. The name assigned is the i-
node number.
NOTE
Checking the raw device is almost always faster.
I-node numbers for . and .. in each directory are not checked for
validity.
SEE ALSO
checkfsys(1M), crash(1M), generic fsck(1M), mkfs(1M), ncheck(1M), fs(4).
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