jfs_fsck - initiate replay of the JFS transaction log, and check and
repair a JFS formatted device
jfs_fsck [ -afnpvV ] [ -j journal_device ] [ --omit_journal_replay ] [
--replay_journal_only ] device
jfs_fsck is used to replay the JFS transaction log, check a JFS
formatted device for errors, and fix any errors found.
device is the special file name corresponding to the actual device to
be checked (e.g. /dev/hdb1).
jfs_fsck must be run as root.
jfs_fsck should only be used to check an unmounted file system or a
file system that is mounted READ ONLY. Using jfs_fsck to check a file
system mounted other than READ ONLY could seriously damage the file
If no options are selected, the default is -p.
-a Autocheck mode - Replay the transaction log. Do not continue
fsck processing unless the aggregate state is dirty or the log
replay failed. Functionally equivalent to -p. Autocheck mode
is typically the default mode used when jfs_fsck is called at
-f Replay the transaction log and force checking even if the file
system appears clean. Repair all problems automatically.
Specify the journal device.
-n Open the file system read only. Do not replay the transaction
log. Report errors, but do not repair them.
Omit the replay of the transaction log. This option should not
be used unless as a last resort (i.e. the log has been severely
corrupted and replaying it causes further problems).
-p Automatically repair ("preen") the file system. Replay the
transaction log. Do not continue fsck processing unless the
aggregate state is dirty or the log replay failed. Functionally
equivalent to -a.
Only replay the transaction log. Do not continue with a full
file system check if the replay fails or if the file system is
still dirty even after a journal replay. In general, this
option should only be used for debugging purposes as it could
leave the file system in an unmountable state. This option
cannot be used with -f, -n, or --omit_journal_replay.
-v Verbose messaging - print details and debug statements to
-V Print version information and exit (regardless of any other
Check the 3rd partition on the 2nd hard disk, print extended
information to stdout, replay the transaction log, force complete
jfs_fsck checking, and give permission to repair all errors:
jfs_fsck -v -f /dev/hdb3
Check the 5th partition on the 1st hard disk, and report, but do not
repair, any errors:
jfs_fsck -n /dev/hda5
The exit code returned by jfs_fsck represents one of the following
0 No errors
1 File system errors corrected and/or transaction log replayed
2 File system errors corrected, system should be rebooted if file
system was mounted
4 File system errors left uncorrected
8 Operational error
16 Usage or syntax error
128 Shared library error
If you find a bug in JFS or jfs_fsck, please report it via the bug
tracking system ("Report Bugs" section) of the JFS project web site:
Please send as much pertinent information as possible, including the
complete output of running jfs_fsck with the -v option on the JFS
fsck(8), jfs_mkfs(8), jfs_fscklog(8), jfs_tune(8), jfs_logdump(8),
Barry Arndt (firstname.lastname@example.org)
William Braswell, Jr.
jfs_fsck is maintained by IBM.
See the JFS project web site for more details:
October 29, 2002 jfs_fsck(8)