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e2fsck.conf(5)		      File Formats Manual		e2fsck.conf(5)

       e2fsck.conf - Configuration file for e2fsck

       e2fsck.conf  is	the configuration file for e2fsck(8).  It controls the
       default behavior of e2fsck(8) while it is checking ext2, ext3, or  ext4

       The  e2fsck.conf	 file uses an INI-style format.	 Stanzas, or top-level
       sections, are delimited by square braces: [ ].	Within	each  section,
       each  line  defines  a  relation, which assigns tags to values, or to a
       subsection, which contains further relations or subsections.  An	 exam-
       ple  of	the  INI-style	format used by this configuration file follows

		 tag1 = value_a
		 tag1 = value_b
		 tag2 = value_c

	    [section 2]
		 tag3 = {
		      subtag1 = subtag_value_a
		      subtag1 = subtag_value_b
		      subtag2 = subtag_value_c
		 tag1 = value_d
		 tag2 = value_e

       Comments are delimited by a semicolon (';') or a hash  ('#')  character
       at  the beginning of the comment, and are terminated by the end of line

       Tags and values must be quoted using double quotes if they contain spa-
       ces.   Within  a	 quoted string, the standard backslash interpretations
       apply: "\n" (for the newline character), "\t" (for the tab  character),
       "\b" (for the backspace character), and "\\" (for the backslash charac-

       The following stanzas are used in the e2fsck.conf file.	They  will  be
       described in more detail in future sections of this document.

	      This   stanza  contains  general	configuration  parameters  for
	      e2fsck's behavior.

	      This stanza allows the administrator to reconfigure  how	e2fsck
	      handles various filesystem inconsistencies.

	      This  stanza  controls  when  e2fsck will attempt to use scratch
	      files to reduce the need for memory.

THE [options] STANZA
       The following relations are defined in the [options] stanza.

	      If this relation is set to a boolean value of true, then if  the
	      user  interrupts	e2fsck	using  ^C,  and	 the filesystem is not
	      explicitly flagged as containing errors, e2fsck will  exit  with
	      an  exit	status	of  0 instead of 32.  This setting defaults to

	      Unfortunately, due to Windows' unfortunate  design  decision  to
	      configure	 the  hardware clock to tick localtime, instead of the
	      more proper and less error-prone UTC time, many users end up  in
	      the  situation  where the system clock is incorrectly set at the
	      time when e2fsck is run.

	      Historically this was usually due to some	 distributions	having
	      buggy  init  scripts  and/or  installers	that  didn't correctly
	      detect this case and take appropriate countermeasures.  Unfortu-
	      nately,  this  is occasionally true even today, usually due to a
	      buggy or misconfigured virtualization manager or	the  installer
	      not  having access to a network time server during the installa-
	      tion process.  So by default, we allow the superblock  times  to
	      be  fudged  by  up to 24 hours.  This can be disabled by setting
	      accept_time_fudge to the boolean value of false.	 This  setting
	      defaults to true.

	      The  e2fsck(8)  program has some heuristics that assume that the
	      system clock is correct.	In addition, many system programs make
	      similar  assumptions.   For example, the UUID library depends on
	      time not going backwards in order for it to be able to make  its
	      guarantees  about issuing universally unique ID's.  Systems with
	      broken system clocks, are well, broken.  However, broken	system
	      clocks, particularly in embedded systems, do exist.  E2fsck will
	      attempt to use heuristics to determine if the time  can  not  be
	      trusted; and to skip time-based checks if this is true.  If this
	      boolean is set to true, then e2fsck will always assume that  the
	      system clock can not be trusted.

	      This  boolean  relation  is  an  alias for accept_time_fudge for
	      backwards compatibility; it used to be that the behavior defined
	      by    accept_time_fudge	 above	 defaulted   to	  false,   and
	      buggy_init_scripts would enable  superblock  time	 field	to  be
	      wrong  by	 up to 24 hours.  When we changed the default, we also
	      renamed this boolean relation to accept_time_fudge.

	      This boolean relation controls whether  or  not  e2fsck(8)  will
	      offer to clear the test_fs flag if the ext4 filesystem is avail-
	      able on the system.  It defaults to true.

	      This boolean relation  controls  whether	or  not	 the  interval
	      between  filesystem  checks  (either  based on time or number of
	      mounts) should be doubled if the system is running  on  battery.
	      This setting defaults to true.

	      When  e2fsck(8)  repacks a indexed directory, reserve the speci-
	      fied percentage of empty space in each leaf nodes so that a  few
	      new entries can be added to the directory without splitting leaf
	      nodes, so that the average fill  ratio  of  directories  can  be
	      maintained  at  a	 higher,  more efficient level.	 This relation
	      defaults to 20 percent.

	      If the log_filename relation contains a relative pathname,  then
	      the  log	file  will  be	placed	in  the directory named by the
	      log_dir relation.

	      This relation contains an alternate directory that will be  used
	      if the directory specified by log_dir is not available or is not

	      If this boolean relation is true, them if the directories speci-
	      fied by log_dir or log_dir_fallback are not available or are not
	      yet writeable, e2fsck will save the output in a  memory  buffer,
	      and  a  child  process  will periodically test to see if the log
	      directory has become  available  after  the  boot	 sequence  has
	      mounted  the  requiste  file  system  for reading/writing.  This
	      implements the functionality provided by logsave(8)  for	e2fsck
	      log files.

	      This  relation  specifies the file name where a copy of e2fsck's
	      output will be written.	If certain problem  reports  are  sup-
	      pressed  using  the  max_count_problems  relation, (or on a per-
	      problem basis using the max_count relation),  the	 full  set  of
	      problem  reports	will be written to the log file.  The filename
	      may contain various percent-expressions (%D, %T, %N, etc.) which
	      will  be	expanded  so  that  the file name for the log file can
	      include things like date, time, device name, and other  run-time
	      parameters.  See the LOGGING section for more details.

	      This relation specifies the maximum number of problem reports of
	      a particular type will be printed to stdout before further prob-
	      lem  reports  of that type are squelched.	 This can be useful if
	      the console is slow (i.e., connected to a serial port) and so  a
	      large  amount  of	 output could end up delaying the boot process
	      for a long time (potentially hours).

	      Do not offer to optimize the extent tree by eliminating unneces-
	      sary width or depth.

	      Use  this percentage of memory to try to read in metadata blocks
	      ahead of the main e2fsck thread.	This should reduce run	times,
	      depending	 on the speed of the underlying storage and the amount
	      of free memory.  There is no default, but see  readahead_kb  for
	      more details.

	      Use  this	 amount	 of memory to read in metadata blocks ahead of
	      the main checking thread.	 Setting this value to	zero  disables
	      readahead	 entirely.   By	 default,  this is set the size of two
	      block groups' inode tables (typically 4MiB  on  a	 regular  ext4
	      filesystem);  if this amount is more than 1/50th of total physi-
	      cal memory, readahead is disabled.

	      If this boolean relation is true, e2fsck	will  print  the  file
	      system  features	as part of its verbose reporting (i.e., if the
	      -v option is specified)

	      If this boolean relation is true, e2fsck	will  run  as  if  the
	      options  -tt  are	 always	 specified.  This will cause e2fsck to
	      print timing statistics on a pass by pass basis  for  full  file
	      system checks.

	      If  this	boolean	 relation  is  true, e2fsck will run as if the
	      option -v is always specified.  This will cause e2fsck to	 print
	      some  additional information at the end of each full file system

THE [problems] STANZA
       Each tag in the [problems] stanza names a problem code specified with a
       leading	"0x"  followed	by  six hex digits.  The value of the tag is a
       subsection where the relations in that subsection override the  default
       treatment of that particular problem code.

       Note  that  inappropriate  settings  in this stanza may cause e2fsck to
       behave incorrectly, or even crash.  Most system	administrators	should
       not be making changes to this section without referring to source code.

       Within each problem code's subsection, the following tags may be used:

	      This  relation  allows  the  message  which is printed when this
	      filesystem inconsistency is detected to be overridden.

	      This boolean relation overrides the default behavior controlling
	      whether  this  filesystem	 problem should be automatically fixed
	      when e2fsck is running in preen mode.

	      This integer relation overrides the max_count_problems parameter
	      (set in the options section) for this particular problem.

       no_ok  This boolean relation overrides the default behavior determining
	      whether or not the filesystem will be marked as inconsistent  if
	      the user declines to fix the reported problem.

	      This  boolean  relation overrides whether the default answer for
	      this problem (or question) should be "no".

	      This boolean relation overrides the default behavior controlling
	      whether  or  not	the  description  for  this filesystem problem
	      should be suppressed when e2fsck is running in preen mode.

	      This boolean relation overrides the default behavior controlling
	      whether  or  not	the  description  for  this filesystem problem
	      should be suppressed when a problem  forced  not	to  be	fixed,
	      either  because  e2fsck is run with the -n option or because the
	      force_no flag has been set for the problem.

	      This boolean option, if set to true, forces a problem  to	 never
	      be  fixed.   That is, it will be as if the user problem responds
	      'no' to the question of 'should this problem  be	fixed?'.   The
	      force_no	option	even overrides the -y option given on the com-
	      mand-line (just for the specific problem, of course).

	      This boolean option, it set to true, marks the  problem  as  one
	      where if the user gives permission to make the requested change,
	      it does not mean that the file system had a  problem  which  has
	      since  been  fixed.   This  is used for requests to optimize the
	      file system's data structure, such as pruning an extent tree.

THE [scratch_files] STANZA
       The following relations are defined in the [scratch_files] stanza.

	      If the directory named by this relation exists and is writeable,
	      then  e2fsck will attempt to use this directory to store scratch
	      files instead of using in-memory data structures.

	      If this relation is set, then in-memory data structures be  used
	      if  the  number  of directories in the filesystem are fewer than
	      amount specified.

	      This relation controls whether or not the scratch file directory
	      is  used	instead	 of  an in-memory data structure for directory
	      information.  It defaults to true.

       icount This relation controls whether or not the scratch file directory
	      is  used	instead	 of  an in-memory data structure when tracking
	      inode counts.  It defaults to true.

       E2fsck has the facility to save the information from an e2fsck run in a
       directory so that a system administrator can review its output at their
       leisure.	 This allows information captured during the automatic	e2fsck
       preen  run,  as	well as a manually started e2fsck run, to be saved for
       posterity.  This facility is controlled by the  log_filename,  log_dir,
       log_dir_fallback, and log_dir_wait relations in the [options] stanza.

       The  filename in log_filename may contain the following percent-expres-
       sions that will be expanded as follows.

       %d     The current day of the month

       %D     The current date; this is a equivalent of %Y%m%d

       %h     The hostname of the system.

       %H     The current hour in 24-hour format (00..23)

       %m     The current month as a two-digit number (01..12)

       %M     The current minute (00..59)

       %N     The name of the block device containing the  file	 system,  with
	      any directory pathname stripped off.

       %p     The pid of the e2fsck process

       %s     The  current  time  expressed  as	 the  number  of seconds since
	      1970-01-01 00:00:00 UTC

       %S     The current second (00..59)

       %T     The current time; this is equivalent of %H%M%S

       %u     The name of the user running e2fsck.

       %U     This percent expression does not expand to anything, but it sig-
	      nals  that  any  following  date	or  time expressions should be
	      expressed in UTC time instead of the local timzeone.

       %y     The last two digits of the current year (00..99)

       %Y     The current year (i.e., 2012).

       The following recipe will prevent e2fsck from aborting during the  boot
       process when a filesystem contains orphaned files.  (Of course, this is
       not always a good idea, since critical files that are  needed  for  the
       security	 of  the  system  could	 potentially end up in lost+found, and
       starting the system without first having a system  administrator	 check
       things out may be dangerous.)

		 0x040002 = {
		      preen_ok = true
		      description = "@u @i %i.	"

       The  following recipe will cause an e2fsck logfile to be written to the
       directory /var/log/e2fsck, with a filename  that	 contains  the	device
       name,  the  hostname  of the system, the date, and time: e.g., "e2fsck-
       sda3.server.INFO.20120314-112142".    If	  the	directory   containing
       /var/log	 is located on the root file system which is initially mounted
       read-only, then the output will be saved in memory and written out once
       the root file system has been remounted read/write.   To avoid too much
       detail from being written to the serial	console	 (which	 could	poten-
       tially  slow  down  the	boot  sequence),  only	print  no more than 16
       instances of each type of file system corruption.

		 max_count_problems = 16
		 log_dir = /var/log/e2fsck
		 log_filename = e2fsck-%N.%h.INFO.%D-%T
		 log_dir_wait = true

	      The configuration file for e2fsck(8).


E2fsprogs version 1.43.5	  August 2017			e2fsck.conf(5)