fsck_ufs(1M)


fsck_ufs -- filesystem consistency check and interactive repair

Synopsis

fsck [-F ufs] [generic_options] [special ...]

fsck [-F ufs] [generic_options] [(-y|-Y)|(-n|-N)] [-o p,b=blkno] [-w] [special . . .]

Description

generic_options are options supported by the generic fsck command.

fsck audits and interactively repairs inconsistent conditions on filesystems. In this case, it asks for confirmation before attempting any corrections. Inconsistencies other than those mentioned above can often result in some loss of data. The amount and severity of data lost can be determined from the diagnostic output.

fsck corrects innocuous inconsistencies such as: unreferenced inodes, incorrect link count of inodes, missing blocks in the free list, blocks appearing in the free list and also in files, or incorrect counts in the super block, automatically. It displays a message for each inconsistency corrected that identifies the nature of, and file system on which, the correction is to take place. After successfully correcting a filesystem, fsck prints the number of files on that filesystem, the number of used and free blocks, and the percentage of fragmentation.

The default action for each correction is to wait for the operator to respond either yes or no. If the operator does not have write permission on the filesystem, fsck will default to a -n (no corrections) action.

Inconsistencies checked are as follows:

Orphaned files and directories (allocated but unreferenced) are, with the operator's concurrence, reconnected by placing them in the lost+found directory. The name assigned is the inode number. If the lost+found directory does not exist, it is created. If there is insufficient space its size is increased.

A filesystem may be specified by giving the name of the block or character special device on which it resides, or by giving the name of its mount point.

ufs-specific options

-F ufs
Specifies the ufs-FSType.

-y | -Y
Assume a yes response to all questions asked by fsck.

-n | -N
Assume a no response to all questions asked by fsck; do not open the filesystem for writing.

-o
Specify the options specific to the ufs filesystem. These options can be any combination of the following:

p
Check the filesystem non-interactively. Exit if there is a problem requiring intervention.

b=blkno
Use blkno as the super block for the filesystem. Block 32 is always an alternate super block.

-w
Only check writeable filesystems.

References

crash(1M), fs_ufs(4), generic fsck(1M), generic mkfs(1M)

Notices

Checking the character special device is almost always faster.
30 January 1998
© 1998 The Santa Cruz Operation, Inc. All rights reserved.