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E2FSCK(8)							     E2FSCK(8)

       e2fsck - check a Linux ext2/ext3 file system

       e2fsck [ -pacnyrdfkvstDFSV ] [ -b superblock ] [ -B blocksize ] [ -l|-L
       bad_blocks_file	]  [  -C  fd  ]  [  -j	 external-journal   ]	[   -E
       extended_options ] device

       e2fsck  is  used to check a Linux second extended file system (ext2fs).
       E2fsck also supports ext2 filesystems containing a journal,  which  are
       also sometimes known as ext3 filesystems, by first applying the journal
       to the filesystem before  continuing  with  normal  e2fsck  processing.
       After  the  journal  has  been  applied,  a filesystem will normally be
       marked as clean.  Hence, for ext3 filesystems, e2fsck will normally run
       the  journal  and  exit,  unless  its superblock indicates that further
       checking is required.

       device is  the  device  file  where  the  filesystem  is  stored  (e.g.

       Note  that  in general it is not safe to run e2fsck on mounted filesys
       tems.  The only exception is if the -n option is specified, and -c, -l,
       or  -L  options	are not specified.   However, even if it is safe to do
       so, the results printed by e2fsck are not valid if  the	filesystem  is
       mounted.    If e2fsck asks whether or not you should check a filesystem
       which is mounted, the only correct answer is no.  Only experts  who
       really know what they are doing should consider answering this question
       in any other way.

       -a     This option does the same thing as the -p option.   It  is  pro
	      vided  for  backwards  compatibility  only; it is suggested that
	      people use -p option whenever possible.

       -b superblock
	      Instead of using	the  normal  superblock,  use  an  alternative
	      superblock  specified  by  superblock.   This option is normally
	      used when the primary superblock has been corrupted.  The  loca
	      tion  of	the backup superblock is dependent on the filesystems
	      blocksize.   For	filesystems  with  1k  blocksizes,  a	backup
	      superblock  can  be found at block 8193; for filesystems with 2k
	      blocksizes, at block 16384; and  for  4k	blocksizes,  at  block

	      Additional  backup  superblocks  can  be determined by using the
	      mke2fs program using the	-n  option  to	print  out  where  the
	      superblocks were created.   The -b option to mke2fs, which spec
	      ifies blocksize of the filesystem must be specified in order for
	      the superblock locations that are printed out to be accurate.

	      If  an alternative superblock is specified and the filesystem is
	      not opened read-only, e2fsck will make  sure  that  the  primary
	      superblock  is  updated  appropriately  upon  completion	of the
	      filesystem check.

       -B blocksize
	      Normally, e2fsck will search for the superblock at various  dif
	      ferent  block  sizes in an attempt to find the appropriate block
	      size.  This search can be fooled in  some  cases.   This	option
	      forces  e2fsck to only try locating the superblock at a particu
	      lar blocksize.  If the superblock  is  not  found,  e2fsck  will
	      terminate with a fatal error.

       -c     This  option  causes  e2fsck to use badblocks(8) program to do a
	      read-only scan of the device in order to find  any  bad  blocks.
	      If  any  bad  blocks  are found, they are added to the bad block
	      inode to prevent them from being allocated to a file  or	direc
	      tory.   If  this	option	is specified twice, then the bad block
	      scan will be done using a non-destructive read-write test.

       -C fd  This option causes e2fsck to write completion information to the
	      specified file descriptor so that the progress of the filesystem
	      check can be monitored.  This option is typically used  by  pro
	      grams  which  are running e2fsck.  If the file descriptor speci
	      fied is 0, e2fsck will print a completion bar as it  goes  about
	      its  business.   This requires that e2fsck is running on a video
	      console or terminal.

       -d     Print  debugging	output	(useless  unless  you  are   debugging

       -D     Optimize	directories  in filesystem.  This option causes e2fsck
	      to try to optimize all directories, either by reindexing them if
	      the  filesystem  supports directory indexing,  or by sorting and
	      compressing directories for smaller directories, or for filesys
	      tems using traditional linear directories.

       -E extended_options
	      Set  e2fsck  extended options.  Extended options are comma sepa
	      rated, and may take an argument using  the  equals  (=)  sign.
	      The following options are supported:

			  Assume  the  format of the extended attribute blocks
			  in the filesystem is the specified  version  number.
			  The  version	number	may  be  1  or 2.  The default
			  extended attribute version format is 2.

       -f     Force checking even if the file system seems clean.

       -F     Flush the filesystem devices buffer  caches  before  beginning.
	      Only really useful for doing e2fsck time trials.

       -j external-journal
	      Set  the pathname where the external-journal for this filesystem
	      can be found.

       -k     When combined with the -c option, any existing bad blocks in the
	      bad  blocks  list are preserved, and any new bad blocks found by
	      running badblocks(8) will be added to the  existing  bad	blocks

       -l filename
	      Add  the	block numbers listed in the file specified by filename
	      to the list of bad blocks.  The format of this file is the  same
	      as the one generated by the badblocks(8) program.  Note that the
	      block numbers are based on  the  blocksize  of  the  filesystem.
	      Hence,  badblocks(8) must be given the blocksize of the filesys
	      tem in order to obtain correct results.  As a result, it is much
	      simpler  and safer to use the -c option to e2fsck, since it will
	      assure that the correct parameters are passed to	the  badblocks

       -L filename
	      Set  the	bad  blocks list to be the list of blocks specified by
	      filename.  (This option is the same as the -l option, except the
	      bad  blocks list is cleared before the blocks listed in the file
	      are added to the bad blocks list.)

       -n     Open the filesystem read-only, and assume an answer of  no  to
	      all  questions.	Allows	e2fsck	to  be used non-interactively.
	      (Note: if the -c, -l, or -L options are specified in addition to
	      the -n option, then the filesystem will be opened read-write, to
	      permit the bad-blocks list to be	updated.   However,  no  other
	      changes will be made to the filesystem.)	This option may not be
	      specified at the same time as the -p or -y options.

       -p     Automatically repair ("preen") the  file	system.   This	option
	      will  case  e2fsck  to automatically fix any filesystem problems
	      that can be safely fixed without human intervention.  If	e2fsck
	      discovers  a  problem which may require the system administrator
	      to take  additional  corrective  action,	e2fsck	will  print  a
	      description  of the problem and then exit with the value 4 logi
	      cally ored into the exit code.  (See the	EXIT  CODE  section.)
	      This  option  is normally used by the systems boot scripts.  It
	      may not be specified at the same time as the -n or -y options.

       -r     This option does nothing at all; it is provided only  for  back
	      wards compatibility.

       -s     This  option  will  byte-swap the filesystem so that it is using
	      the normalized, standard byte-order (which  is  i386  or	little
	      endian).	 If  the  filesystem  is already in the standard byte-
	      order, e2fsck will take no action.

       -S     This option will byte-swap the  filesystem,  regardless  of  its
	      current byte-order.

       -t     Print  timing  statistics  for  e2fsck.	If this option is used
	      twice, additional timing statistics are printed  on  a  pass  by
	      pass basis.

       -v     Verbose mode.

       -V     Print version information and exit.

       -y     Assume  an answer of yes to all questions; allows e2fsck to be
	      used non-interactively.  This option may not be specified at the
	      same time as the -n or -p options.

       The  exit  code	returned  by e2fsck is the sum of the following condi
	    0	 - No errors
	    1	 - File system errors corrected
	    2	 - File system errors corrected, system should
		   be rebooted
	    4	 - File system errors left uncorrected
	    8	 - Operational error
	    16	 - Usage or syntax error
	    32	 - E2fsck canceled by user request
	    128  - Shared library error

       The following signals have the following effect when sent to e2fsck.

	      This signal causes e2fsck to start displaying a completion  bar.
	      (See discussion of the -C option.)

	      This signal causes e2fsck to stop displaying a completion bar.

       Almost  any  piece of software will have bugs.  If you manage to find a
       filesystem which causes e2fsck to crash, or which e2fsck is  unable  to
       repair, please report it to the author.

       Please  include	as  much  information  as possible in your bug report.
       Ideally, include a complete transcript of the e2fsck run, so I can  see
       exactly	what  error  messages  are displayed.  (Make sure the messages
       printed by e2fsck are in English; if your system has been configured so
       that  e2fscks  messages	have  been  translated into another language,
       please set the the LC_ALL environment variable to C so that  the  tran
       script  of  e2fscks  output  will  be  useful  to  me.)	If you have a
       writable filesystem where the transcript can be stored,	the  script(1)
       program is a handy way to save the output of e2fsck to a file.

       It  is  also  useful  to send the output of dumpe2fs(8).  If a specific
       inode or inodes seems to be giving  e2fsck  trouble,  try  running  the
       debugfs(8)  command  and send the output of the stat(1u) command run on
       the relevant inode(s).  If the inode is a directory, the  debugfs  dump
       command	will allow you to extract the contents of the directory inode,
       which can sent to me after being first run  through  uuencode(1).   The
       most useful data you can send to help reproduce the bug is a compressed
       raw image dump of the filesystem, generated using e2image(8).  See  the
       e2image(8) man page for more details.

       Always include the full version string which e2fsck displays when it is
       run, so I know which version you are running.

       This version of e2fsck was written by Theodore Tso .

       badblocks(8),   dumpe2fs(8),   debugfs(8),    e2image(8),    mke2fs(8),

E2fsprogs version 1.40-WIP	 November 2006			     E2FSCK(8)

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