add new superblock field: s_overhead_blocks

[tools/e2fsprogs.git] / e2fsck / e2fsck.conf.5.in

diff --git a/e2fsck/e2fsck.conf.5.in b/e2fsck/e2fsck.conf.5.in
index 6638a39..e09cd6d 100644 (file)
--- a/e2fsck/e2fsck.conf.5.in
+++ b/e2fsck/e2fsck.conf.5.in
@@ -11,7 +11,7 @@ is the configuration file for
 .BR e2fsck (8).  
 It controls the default behavior of 
 .BR e2fsck (8)
-while it is checking ext2 or ext3 filesystems.
+while it is checking ext2, ext3, or ext4 filesystems.
 .PP
 The
 .I e2fsck.conf
@@ -87,19 +87,41 @@ 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 false.
 .TP
-.I buggy_init_scripts
-Some buggy distributions (such as Ubuntu) have init scripts and/or
-installers which fail to correctly set the system clock before running
-e2fsck and/or formatting the filesystem initially.  Normally this
-happens because the hardware clock is ticking localtime, instead of the
-more proper and less error-prone UTC time.  So while the kernel is
-booting, the system time (which in Linux systems always ticks in UTC
-time) is set from the hardware clock, but since the hardware clock is
-ticking localtime, the system time is incorrect.  Unfortunately, some
-buggy distributions do not correct this before running e2fsck.  If this
-option is set to a boolean value of true, we attempt to work around this
-situation by allowing the superblock last write time, last mount time,
-and last check time to be in the future by up to 24 hours.
+.I accept_time_fudge
+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.
+.IP
+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.  However, it's still possible, despite the
+best efforts of init script and installer authors to not be
+able to detect this misconfiguration, usually due to a
+buggy or misconfigured virtualization manager or the
+installer not having access to a network time server
+during the installation process.  So by default, we allow
+the superblock times to be fudged by up to 24 hours.
+This can be disabled by setting
+.I accept_time_fudge
+to the
+boolean value of false.  This setting defaults to true.
+.TP
+.I broken_system_clock
+The
+.BR e2fsck (8)
+program has some hueristics 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 hueristics to determine if the time
+can no tbe 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.
 .TP
 .I clear_test_fs_flag
 This boolean relation controls whether or not 
@@ -111,7 +133,7 @@ defaults to true.
 .I defer_check_on_battery
 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.  It defaults to 
+be doubled if the system is running on battery.  This setting defaults to 
 true.
 .TP
 .I indexed_dir_slack_percentage
@@ -168,11 +190,22 @@ is running in preen mode.
 .I no_nomsg
 This boolean relation overrides the default behavior controlling 
 whether or not the description for this filesystem problem should
-be suppressed when
+be suppressed when a problem forced not to be fixed, either because
 .B e2fsck
 is run with the
 .B -n
-option.
+option or because the
+.I force_no
+flag has been set for the problem.
+.TP
+.I force_no
+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
+.I force_no
+option even overrides the
+.B -y
+option given on the command-line (just for the specific problem, of course).
 .SH THE [scratch_files] STANZA
 The following relations are defined in the 
 .I [scratch_files]