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fsck(1M)							      fsck(1M)

NAME
       fsck - check and	repair file systems

SYNOPSIS
       fsck [-F	FSType]	[-m] [-V] [special...]

       fsck  [-F FSType]  [-n  | N | y | Y]  [-V] [-o FSType-specific-options]
       [special...]

       fsck audits and interactively repairs inconsistent file	system	condi-
       tions.  If  the file system is inconsistent the default action for each
       correction is to	wait for the user to respond yes or no.	 If  the  user
       does  not have write permission fsck defaults to	a no action. Some cor-
       rective actions will result in loss of data. The	amount and severity of
       data loss can be	determined from	the diagnostic output.

       FSType-specific-options	are  options  specified	 in  a comma-separated
       (with no	intervening spaces) list of options or keyword-attribute pairs
       for interpretation by the FSType-specific module	of the command.

       special	represents the character special device	on which the file sys-
       tem resides, for	example, /dev/rdsk/c1t0d0s7. Note: the character  spe-
       cial  device,  not  the block special device, should be used. fsck will
       not work	if the block device is mounted.

       If no special device is specified fsck checks the file  systems	listed
       in  /etc/vfstab.	  Those	 entries in /etc/vfstab	which have a character
       special device entry in the fsckdev field and have a  non-zero  numeric
       entry  in the fsckpass field will be checked. Specifying	-F FSType lim-
       its the file systems to be checked to those of the type indicated.

       If special is specified,	but -F is not, the file	system	type  will  be
       determined  by looking for a matching entry in /etc/vfstab. If no entry
       is found, the default local file	 system	 type  specified  in  /etc/de-
       fault/fs	will be	used.

       If  a  file  system  type supports parallel checking, for example, ufs,
       some file systems eligible for checking may  be	checked	 in  parallel.
       Consult	the  file system-specific man page (for	example, fsck_ufs(1M))
       for more	information.

       The following generic options are supported:

       -F FSType	       Specify the file	system type on which to	 oper-
			       ate.

       -m		       Check  but  do  not  repair. This option	checks
			       that the	file system is suitable	for  mounting,
			       returning  the  appropriate exit	status.	If the
			       file system is ready for	 mounting,  fsck  dis-
			       plays a message such as:

			       ufs fsck: sanity	check: /dev/rdsk/c0t3d0s1 okay

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

       -V		       Echo the	expanded command line but do not  exe-
			       cute  the  command.  This option	may be used to
			       verify and to validate the command line.

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

       -o specific-options     These  specific-options	can be any combination
			       of the following	separated by commas  (with  no
			       intervening spaces).

			       b=n

				   Use block n as the super block for the file
				   system. Block 32 is always one of  the  al-
				   ternate  super blocks.  Determine the loca-
				   tion	 of  other  super  blocks  by  running
				   newfs(1M) with the -Nv options specified.

			       c

				   If  the  file  system is in the old (static
				   table) format, convert it to	the  new  (dy-
				   namic  table) format. If the	file system is
				   in the new format, convert it  to  the  old
				   format  provided the	old format can support
				   the file system configuration.  In interac-
				   tive	mode, fsck will	list the direction the
				   conversion is to be made  and  ask  whether
				   the	conversion  should be done. If a nega-
				   tive	answer is given, no further operations
				   are done on the file	system.	In preen mode,
				   the direction of the	conversion  is	listed
				   and	done if	possible without user interac-
				   tion. Conversion in preen mode is best used
				   when	 all  the  file	systems	are being con-
				   verted at once. The format of a file	system
				   can	be  determined	from the first line of
				   output from fstyp(1M).  Note: the c	option
				   is  seldom  used  and  is included only for
				   compatibility with pre-4.1 releases.	 There
				   is  no  guarantee  that this	option will be
				   included in future releases.

			       f

				   Force checking of file  systems  regardless
				   of  the  state  of  their super block clean
				   flag.

			       p

				   Check and fix the file system  non-interac-
				   tively ("preen"). Exit immediately if there
				   is a	problem	requiring  intervention.  This
				   option  is required to enable parallel file
				   system checking.

			       w

				   Check writable file systems only.

       0	file system is okay and	does not need checking

       1	erroneous parameters are specified

       32	file system is unmounted and needs checking (fsck -monly)

       33	file system is already mounted

       34	cannot stat device

       36	uncorrectable errors detected -	terminate normally

       37	a signal was caught during processing

       39	uncorrectable errors detected -	terminate immediately

       40	for root, same as 0.

USAGE
       See largefile(5)	for the	description of the behavior of fsck  when  en-
       countering files	greater	than or	equal to 2 Gbyte (2**31	bytes).

       /etc/default/fs	       default	local file system type.	Default	values
			       can be set for the following flags in  /etc/de-
			       fault/fs. For example: LOCAL=ufs.

			       LOCAL	The default partition for a command if
					no FSType is specified.

       /etc/vfstab	       list of default parameters for each file	system

       See attributes(5) for descriptions of the following attributes:

       +-----------------------------+-----------------------------+
       |      ATTRIBUTE	TYPE	     |	    ATTRIBUTE VALUE	   |
       +-----------------------------+-----------------------------+
       |Availability		     |SUNWcsu			   |
       +-----------------------------+-----------------------------+

       clri(1M), fsck_cachefs(1M),  fsck_ufs(1M),  fsdb_ufs(1M),  fsirand(1M),
       fstyp(1M),  mkfs(1M),  mkfs_ufs(1M),  mountall(1M),  newfs(1M), reboot(
       1M), vfstab(4), attributes(5), largefile(5), ufs(7FS)

WARNINGS
       The operating system buffers  file  system  data.  Running  fsck	 on  a
       mounted	file system can	cause the operating system's buffers to	become
       out of date with	respect	to the disk. For this reason, the file	system
       should  be  unmounted  when fsck	is used. If this is not	possible, care
       should be taken that the	system is quiescent and	that  it  is  rebooted
       immediately  after  fsck	is run.	Quite often, however, this will	not be
       sufficient. A panic will	probably occur if running fsck on a file  sys-
       tem modifies the	file system.

       This command may	not be supported for all FSTypes.

       Running fsck on file systems larger than	2 Gb fails if the user chooses
       to use the block	interface to the device:

       fsck /dev/dsk/c?t?d?s?

       rather than the raw (character special) device:

       fsck /dev/rdsk/c?t?d?s?

       Starting	with Solaris 9,	fsck manages extended attribute	 data  on  the
       disk.  (See fsattr(5) for a description of extended file	attributes.) A
       file system with	extended attributes can	be mounted on versions of  So-
       laris  that  are	not attribute-aware (versions prior to Solaris 9), but
       the attributes will not be accessible and fsck will strip them from the
       files  and  place  them	in  lost+found.	 Once the attributes have been
       stripped, the file system is completely stable on versions  of  Solaris
       that  are not attribute-aware, but would	be considered corrupted	on at-
       tribute-aware versions. In the latter circumstance, run the  attribute-
       aware  fsck  to	stabilize the file system before using it in an	attri-
       bute-aware environment.

				 18 July 2004			      fsck(1M)

NAME | SYNOPSIS | USAGE | WARNINGS

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