jfs_fsck(8)		            	              jfs_fsck(8)



NAME
       jfs_fsck - initiate replay of the JFS transaction log, and
       check and repair a JFS formatted device


SYNOPSIS
       jfs_fsck [ -afnpvV ] [  -j  journal_device  ]  
       [--omit_journal_replay	]  [ --replay_journal_only ] device


DESCRIPTION
       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 filename corresponding to	 the  actual
       device  to  be  checked (e.g. /dev/hdb1).

       jfs_fsck must be run as root.


WARNING
       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 system!


OPTIONS
       If no options are selected, the default is -p.

       -a     Autocheck	 mode  -  Replay  the transaction log.
              Do not continue fsck processing unless the aggre-
	      gate 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 boot time.

       -f     Replay the transaction log and force checking
              even if the file  system appears clean.  Repair
	      all problems automatically.

       -j journal_device
	      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_journal_replay
	      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.

       --replay_journal_only
	      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 stdout.

       -V     Print  version  information  and	exit (regardless
              of any other chosen options).

EXAMPLES
       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



EXIT CODE
       The  exit  code	returned  by jfs_fsck represents one of
       the following conditions:

	0     No errors

	1     File system errors corrected and/or transaction log
	      replayed  successfully

	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


REPORTING BUGS
       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:
       http://oss.software.ibm.com/jfs

       Please send as much pertinent information as possible, 
       including the complete output of running jfs_fsck with
       the -v option on the JFS device.


SEE ALSO
       fsck(8), jfs_mkfs(8), jfs_fscklog(8), jfs_tune(8),
       jfs_logdump(8), jfs_debugfs(8)


AUTHORS
       Barry Arndt  (barndt@us.ibm.com)
       William Braswell, Jr.

       jfs_fsck is maintained by IBM.
       See the JFS project web site for more details:
       http://oss.software.ibm.com/jfs



		 October 29, 2002		      jfs_fsck(8)