fsck_s5(1M)

fsck_s5 -- check and repair s5 filesystems

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.

s5-specific options

-F s5

Specify the s5 FSType. If -F s5 is not specified heuristics similiar to those used by fstyp(1M) are used to determine the file system type.

NOTE: This command executes faster if it is not required to autodetect file system types. If possible, specify the -F s5.

-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 filesystem 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 filesystem. The filesystem 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 does not continue to be used, or is written back to the filesystem.

The -sX suboption allows for creating an optimal free-list organization.

If X is not given, the values used when the filesystem 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 filesystem. Using this option forces a no response to all questions asked by fsck. This is useful for forcing free list reorganization on uncontaminated filesystems.

-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 prompts for the name of the scratch file. The file chosen should not be on the filesystem being checked, and if it is not a special file or did not already exist, it is 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 are 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 is reconstructed if it is necessary.

Inconsistencies checked are as follows:

Blocks claimed by more than one i-node or the free list.
Blocks claimed by an i-node or the free list outside the range of the file system.
Incorrect link counts.
Size checks:
- Incorrect number of blocks.
- Directory size not 16-byte aligned.
Bad i-node format.
Blocks not accounted for anywhere.
Directory checks:
- File pointing to unallocated i-node.
- I-node number out of range.
Super Block checks:
- More than 65536 i-nodes.
- More blocks for i-nodes than there are in the filesystem.
Bad free block list format.
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 is 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 forces the reconnection of nonempty directories. The name assigned is the i-node number.

References

crash(1M), fs_s5(4), generic fsck(1M), fstyp(1M), generic ncheck(1M)

Notices

Checking the raw device is almost always faster.

I-node numbers for ``.'' and ``..'' in each directory are not checked for validity.

When fsck detects an incorrect file size, it prompts you to choose whether you want the file truncated or expanded to match the number of blocks allocated. Increasing the file size may produce unwanted data at the end of your file; truncating the file may destroy data in the last few blocks.