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1<?xml version="1.0" encoding="ISO-8859-1"?>
2<!DOCTYPE sect1 PUBLIC "-//OASIS//DTD DocBook XML V4.5//EN"
3 "" [
4 <!ENTITY % general-entities SYSTEM "../general.ent">
5 <!ENTITY site SYSTEM "../appendices/">
6 %general-entities;
9<sect1 id="ch-config-usage" revision="sysv">
10 <?dbhtml filename="usage.html"?>
12 <title>System V Bootscript Usage and Configuration</title>
14 <indexterm zone="ch-config-usage">
15 <primary sortas="a-Bootscripts">Bootscripts</primary>
16 <secondary>usage</secondary>
17 </indexterm>
19 <sect2>
20 <title>How Do the System V Bootscripts Work?</title>
22 <para>Linux uses a special booting facility named SysVinit that is based on a
23 concept of <emphasis>run-levels</emphasis>. It can be quite different from one
24 system to another, so it cannot be assumed that because things worked in one
25 particular Linux distribution, they should work the same in LFS too. LFS has its
26 own way of doing things, but it respects generally accepted standards.</para>
28 <para>SysVinit (which will be referred to as <quote>init</quote> from now on)
29 works using a run-levels scheme. There are seven (numbered 0 to 6) run-levels
30 (actually, there are more run-levels, but they are for special cases and are
31 generally not used. See <filename>init(8)</filename> for more details), and
32 each one of those corresponds to the actions the computer is supposed to
33 perform when it starts up. The default run-level is 3. Here are the
34 descriptions of the different run-levels as they are implemented:</para>
36<literallayout>0: halt the computer
371: single-user mode
382: multi-user mode without networking
393: multi-user mode with networking
404: reserved for customization, otherwise does the same as 3
415: same as 4, it is usually used for GUI login (like X's <command>xdm</command> or KDE's <command>kdm</command>)
426: reboot the computer</literallayout>
44 </sect2>
46 <sect2 id="conf-sysvinit" role="configuration">
47 <title>Configuring Sysvinit</title>
49 <indexterm zone="conf-sysvinit">
50 <primary sortas="a-Sysvinit">Sysvinit</primary>
51 <secondary>configuring</secondary>
52 </indexterm>
54 <indexterm zone="conf-sysvinit">
55 <primary sortas="e-/etc/inittab">/etc/inittab</primary>
56 </indexterm>
58 <para>During the kernel initialization, the first program that is run
59 is either specified on the command line or, by default
60 <command>init</command>. This program reads the initialization file
61 <filename>/etc/inittab</filename>. Create this file with:</para>
63<screen><userinput>cat &gt; /etc/inittab &lt;&lt; "EOF"
64<literal># Begin /etc/inittab
68si::sysinit:/etc/rc.d/init.d/rc S
70l0:0:wait:/etc/rc.d/init.d/rc 0
71l1:S1:wait:/etc/rc.d/init.d/rc 1
72l2:2:wait:/etc/rc.d/init.d/rc 2
73l3:3:wait:/etc/rc.d/init.d/rc 3
74l4:4:wait:/etc/rc.d/init.d/rc 4
75l5:5:wait:/etc/rc.d/init.d/rc 5
76l6:6:wait:/etc/rc.d/init.d/rc 6
78ca:12345:ctrlaltdel:/sbin/shutdown -t1 -a -r now
821:2345:respawn:/sbin/agetty --noclear tty1 9600
832:2345:respawn:/sbin/agetty tty2 9600
843:2345:respawn:/sbin/agetty tty3 9600
854:2345:respawn:/sbin/agetty tty4 9600
865:2345:respawn:/sbin/agetty tty5 9600
876:2345:respawn:/sbin/agetty tty6 9600
89# End /etc/inittab</literal>
92 <para>An explanation of this initialization file is in the man page for
93 <emphasis>inittab</emphasis>. For LFS, the key command that is run is
94 <command>rc</command>. The initialization file above will instruct
95 <command>rc</command> to run all the scripts starting with an S in the
96 <filename class="directory">/etc/rc.d/rcS.d</filename> directory
97 followed by all the scripts starting with an S in the <filename
98 class="directory">/etc/rc.d/rc?.d</filename> directory where the question
99 mark is specified by the initdefault value.</para>
101 <para>As a convenience, the <command>rc</command> script reads a library of
102 functions in <filename class="directory">/lib/lsb/init-functions</filename>.
103 This library also reads an optional configuration file,
104 <filename>/etc/sysconfig/</filename>. Any of the system
105 configuration file parameters described in subsequent sections can be
106 alternatively placed in this file allowing consolidation of all system
107 parameters in this one file.</para>
109 <para>As a debugging convenience, the functions script also logs all output
110 to <filename>/run/var/bootlog</filename>. Since the <filename
111 class="directory">/run</filename> directory is a tmpfs, this file is not
112 persistent across boots, however it is appended to the more permanent file
113 <filename>/var/log/boot.log</filename> at the end of the boot process.</para>
115 <sect3 id="init-levels" >
116 <title>Changing Run Levels</title>
118 <para>Changing run-levels is done with <command>init
119 <replaceable>&lt;runlevel&gt;</replaceable></command>, where
120 <replaceable>&lt;runlevel&gt;</replaceable> is the target run-level. For example, to
121 reboot the computer, a user could issue the <command>init 6</command> command,
122 which is an alias for the <command>reboot</command> command. Likewise,
123 <command>init 0</command> is an alias for the <command>halt</command>
124 command.</para>
126 <para>There are a number of directories under <filename
127 class="directory">/etc/rc.d</filename> that look like <filename
128 class="directory">rc?.d</filename> (where ? is the number of the run-level) and
129 <filename class="directory">rcsysinit.d</filename>, all containing a number of
130 symbolic links. Some begin with a <emphasis>K</emphasis>, the others begin with
131 an <emphasis>S</emphasis>, and all of them have two numbers following the
132 initial letter. The K means to stop (kill) a service and the S means to start a
133 service. The numbers determine the order in which the scripts are run, from 00
134 to 99&mdash;the lower the number the earlier it gets executed. When
135 <command>init</command> switches to another run-level, the appropriate services
136 are either started or stopped, depending on the runlevel chosen.</para>
138 <para>The real scripts are in <filename
139 class="directory">/etc/rc.d/init.d</filename>. They do the actual work, and
140 the symlinks all point to them. K links and S links point to
141 the same script in <filename class="directory">/etc/rc.d/init.d</filename>.
142 This is because the scripts can be called with different parameters like
143 <parameter>start</parameter>, <parameter>stop</parameter>,
144 <parameter>restart</parameter>, <parameter>reload</parameter>, and
145 <parameter>status</parameter>. When a K link is encountered, the appropriate
146 script is run with the <parameter>stop</parameter> argument. When an S link
147 is encountered, the appropriate script is run with the
148 <parameter>start</parameter> argument.</para>
150 <para>There is one exception to this explanation. Links that start
151 with an <emphasis>S</emphasis> in the <filename
152 class="directory">rc0.d</filename> and <filename
153 class="directory">rc6.d</filename> directories will not cause anything
154 to be started. They will be called with the parameter
155 <parameter>stop</parameter> to stop something. The logic behind this
156 is that when a user is going to reboot or halt the system, nothing
157 needs to be started. The system only needs to be stopped.</para>
159 <para>These are descriptions of what the arguments make the scripts
160 do:</para>
162 <variablelist>
164 <varlistentry>
165 <term><parameter>start</parameter></term>
166 <listitem>
167 <para>The service is started.</para>
168 </listitem>
169 </varlistentry>
171 <varlistentry>
172 <term><parameter>stop</parameter></term>
173 <listitem>
174 <para>The service is stopped.</para>
175 </listitem>
176 </varlistentry>
178 <varlistentry>
179 <term><parameter>restart</parameter></term>
180 <listitem>
181 <para>The service is stopped and then started again.</para>
182 </listitem>
183 </varlistentry>
185 <varlistentry>
186 <term><parameter>reload</parameter></term>
187 <listitem>
188 <para>The configuration of the service is updated.
189 This is used after the configuration file of a service was modified, when
190 the service does not need to be restarted.</para>
191 </listitem>
192 </varlistentry>
194 <varlistentry>
195 <term><parameter>status</parameter></term>
196 <listitem>
197 <para>Tells if the service is running and with which PIDs.</para>
198 </listitem>
199 </varlistentry>
201 </variablelist>
203 <para>Feel free to modify the way the boot process works (after all,
204 it is your own LFS system). The files given here are an example of how
205 it can be done.</para>
207 </sect3>
208 </sect2>
210 <sect2>
211 <title>Udev Bootscripts</title>
213 <para>The <filename>/etc/rc.d/init.d/udev</filename> initscript starts
214 <command>udevd</command>, triggers any "coldplug" devices that have
215 already been created by the kernel and waits for any rules to complete.
216 The script also unsets the uevent handler from the default of
217 <filename>/sbin/hotplug </filename>. This is done because the kernel no
218 longer needs to call out to an external binary. Instead
219 <command>udevd</command> will listen on a netlink socket for uevents that
220 the kernel raises.</para>
222 <para>The <command>/etc/rc.d/init.d/udev_retry</command> initscript takes
223 care of re-triggering events for subsystems whose rules may rely on
224 filesystems that are not mounted until the <command>mountfs</command>
225 script is run (in particular, <filename class="directory">/usr</filename>
226 and <filename class="directory">/var</filename> may cause this). This
227 script runs after the <command>mountfs</command> script, so those rules
228 (if re-triggered) should succeed the second time around. It is
229 configured from the <filename>/etc/sysconfig/udev_retry</filename> file;
230 any words in this file other than comments are considered subsystem names
231 to trigger at retry time. To find the subsystem of a device, use
232 <command>udevadm info --attribute-walk &lt;device&gt;</command> where
233 &lt;device&gt; is an absolute path in /dev or /sys such as /dev/sr0 or
234 /sys/class/rtc.</para>
236 <para>For information on kernel module loading and udev, see
237 <xref linkend="module-loading"/>.</para>
238 </sect2>
240 <sect2 id="ch-config-clock">
241 <title>Configuring the System Clock</title>
243 <indexterm zone="ch-config-clock">
244 <primary sortas="d-setclock">setclock</primary>
245 <secondary>configuring</secondary></indexterm>
247 <para>The <command>setclock</command> script reads the time from the hardware
248 clock, also known as the BIOS or the Complementary Metal Oxide Semiconductor
249 (CMOS) clock. If the hardware clock is set to UTC, this script will convert the
250 hardware clock's time to the local time using the
251 <filename>/etc/localtime</filename> file (which tells the
252 <command>hwclock</command> program which timezone to use). There is no
253 way to detect whether or not the hardware clock is set to UTC, so this
254 needs to be configured manually.</para>
256 <para>The <command>setclock</command> program is run via
257 <application>udev</application> when the kernel detects the hardware
258 capability upon boot. It can also be run manually with the stop parameter to
259 store the system time to the CMOS clock.</para>
261 <para>If you cannot remember whether or not the hardware clock is set to UTC,
262 find out by running the <userinput>hwclock --localtime --show</userinput>
263 command. This will display what the current time is according to the hardware
264 clock. If this time matches whatever your watch says, then the hardware clock is
265 set to local time. If the output from <command>hwclock</command> is not local
266 time, chances are it is set to UTC time. Verify this by adding or subtracting
267 the proper amount of hours for the timezone to the time shown by
268 <command>hwclock</command>. For example, if you are currently in the MST
269 timezone, which is also known as GMT -0700, add seven hours to the local
270 time.</para>
272 <para>Change the value of the <envar>UTC</envar> variable below
273 to a value of <parameter>0</parameter> (zero) if the hardware clock
274 is <emphasis>NOT</emphasis> set to UTC time.</para>
276 <para>Create a new file <filename>/etc/sysconfig/clock</filename> by running
277 the following:</para>
279<screen><userinput>cat &gt; /etc/sysconfig/clock &lt;&lt; "EOF"
280<literal># Begin /etc/sysconfig/clock
284# Set this to any options you might need to give to hwclock,
285# such as machine hardware clock type for Alphas.
288# End /etc/sysconfig/clock</literal>
291 <para>A good hint explaining how to deal with time on LFS is available
292 at <ulink url="&hints-root;time.txt"/>. It explains issues such as
293 time zones, UTC, and the <envar>TZ</envar> environment variable.</para>
295 <note><para>The CLOCKPARAMS and UTC paramaters may also be set
296 in the <filename>/etc/sysconfig/</filename> file.</para></note>
298 </sect2>
300 <sect2 id="ch-config-console">
301 <?dbhtml filename="console.html"?>
303 <title>Configuring the Linux Console</title>
305 <indexterm zone="ch-config-console">
306 <primary sortas="d-console">console</primary>
307 <secondary>configuring</secondary>
308 </indexterm>
310 <para>This section discusses how to configure the <command>console</command>
311 bootscript that sets up the keyboard map, console font, and console kernel log
312 level. If non-ASCII characters (e.g., the copyright sign, the British pound
313 sign and Euro symbol) will not be used and the keyboard is a U.S. one, much
314 of this section can be skipped. Without the configuration file, (or
315 equivalent settings in <filename></filename>), the
316 <command>console</command> bootscript will do nothing.</para>
318 <para>The <command>console</command> script reads the
319 <filename>/etc/sysconfig/console</filename> file for configuration
320 information. Decide which keymap and screen font will be used. Various
321 language-specific HOWTOs can also help with this, see <ulink
322 url=""/>. If still in
323 doubt, look in the <filename class="directory">/usr/share/keymaps</filename>
324 and <filename class="directory">/usr/share/consolefonts</filename> directories
325 for valid keymaps and screen fonts. Read <filename>loadkeys(1)</filename> and
326 <filename>setfont(8)</filename> manual pages to determine the correct
327 arguments for these programs.</para>
329 <para>The <filename>/etc/sysconfig/console</filename> file should contain lines
330 of the form: VARIABLE="value". The following variables are recognized:</para>
331 <variablelist>
333 <varlistentry>
334 <term>LOGLEVEL</term>
335 <listitem>
336 <para>This variable specifies the log level for kernel messages sent
337 to the console as set by <command>dmesg -n</command>. Valid levels are
338 from "1" (no messages) to "8". The default level is "7".</para>
339 </listitem>
340 </varlistentry>
342 <varlistentry>
343 <term>KEYMAP</term>
344 <listitem>
345 <para>This variable specifies the arguments for the
346 <command>loadkeys</command> program, typically, the name of keymap
347 to load, e.g., <quote>it</quote>. If this variable is not set, the
348 bootscript will not run the <command>loadkeys</command> program,
349 and the default kernel keymap will be used. Note that a few keymaps
350 have multiple versions with the same name (cz and its variants in
351 qwerty/ and qwertz/, es in olpc/ and qwerty/, and trf in fgGIod/ and
352 qwerty/). In these cases the parent directory should also be specified
353 (e.g. qwerty/es) to ensure the proper keymap is loaded.
354 </para>
355 </listitem>
356 </varlistentry>
358 <varlistentry>
359 <term>KEYMAP_CORRECTIONS</term>
360 <listitem>
361 <para>This (rarely used) variable
362 specifies the arguments for the second call to the
363 <command>loadkeys</command> program. This is useful if the stock keymap
364 is not completely satisfactory and a small adjustment has to be made. E.g.,
365 to include the Euro sign into a keymap that normally doesn't have it,
366 set this variable to <quote>euro2</quote>.</para>
367 </listitem>
368 </varlistentry>
370 <varlistentry>
371 <term>FONT</term>
372 <listitem>
373 <para>This variable specifies the arguments for the
374 <command>setfont</command> program. Typically, this includes the font
375 name, <quote>-m</quote>, and the name of the application character
376 map to load. E.g., in order to load the <quote>lat1-16</quote> font
377 together with the <quote>8859-1</quote> application character map
378 (as it is appropriate in the USA),
379 <!-- because of the copyright sign -->
380 set this variable to <quote>lat1-16 -m 8859-1</quote>.
381 In UTF-8 mode, the kernel uses the application character map for
382 conversion of composed 8-bit key codes in the keymap to UTF-8, and thus
383 the argument of the "-m" parameter should be set to the encoding of the
384 composed key codes in the keymap.</para>
386 </listitem>
387 </varlistentry>
389 <varlistentry>
390 <term>UNICODE</term>
391 <listitem>
392 <para>Set this variable to <quote>1</quote>, <quote>yes</quote> or
393 <quote>true</quote> in order to put the
394 console into UTF-8 mode. This is useful in UTF-8 based locales and
395 harmful otherwise.</para>
396 </listitem>
397 </varlistentry>
399 <varlistentry>
400 <term>LEGACY_CHARSET</term>
401 <listitem>
402 <para>For many keyboard layouts, there is no stock Unicode keymap in
403 the Kbd package. The <command>console</command> bootscript will
404 convert an available keymap to UTF-8 on the fly if this variable is
405 set to the encoding of the available non-UTF-8 keymap.</para>
406 </listitem>
407 </varlistentry>
409 </variablelist>
411 <para>Some examples:</para>
413 <itemizedlist>
415 <listitem>
416 <para>For a non-Unicode setup, only the KEYMAP and FONT variables are
417 generally needed. E.g., for a Polish setup, one would use:</para>
418<screen role="nodump"><userinput>cat &gt; /etc/sysconfig/console &lt;&lt; "EOF"
419<literal># Begin /etc/sysconfig/console
422FONT="lat2a-16 -m 8859-2"
424# End /etc/sysconfig/console</literal>
426 </listitem>
428 <listitem>
429 <para>As mentioned above, it is sometimes necessary to adjust a
430 stock keymap slightly. The following example adds the Euro symbol to the
431 German keymap:</para>
433<screen role="nodump"><userinput>cat &gt; /etc/sysconfig/console &lt;&lt; "EOF"
434<literal># Begin /etc/sysconfig/console
438FONT="lat0-16 -m 8859-15"
441# End /etc/sysconfig/console</literal>
443 </listitem>
445 <listitem>
446 <para>The following is a Unicode-enabled example for Bulgarian, where a
447 stock UTF-8 keymap exists:</para>
448<!-- This is what is used by jhalfs for creating the console file: whenever
449 you change the following, please inform the jhalfs maintainer(s). -->
450<screen><userinput>cat &gt; /etc/sysconfig/console &lt;&lt; "EOF"
451<literal># Begin /etc/sysconfig/console
457# End /etc/sysconfig/console</literal>
459 </listitem>
461 <listitem>
462 <para>Due to the use of a 512-glyph LatArCyrHeb-16 font in the previous
463 example, bright colors are no longer available on the Linux console unless
464 a framebuffer is used. If one wants to have bright colors without a
465 framebuffer and can live without characters not belonging to his language,
466 it is still possible to use a language-specific 256-glyph font, as
467 illustrated below:</para>
469<screen role="nodump"><userinput>cat &gt; /etc/sysconfig/console &lt;&lt; "EOF"
470<literal># Begin /etc/sysconfig/console
476# End /etc/sysconfig/console</literal>
478 </listitem>
480 <listitem>
481 <para>The following example illustrates keymap autoconversion from
482 ISO-8859-15 to UTF-8 and enabling dead keys in Unicode mode:</para>
484<screen role="nodump"><userinput>cat &gt; /etc/sysconfig/console &lt;&lt; "EOF"
485<literal># Begin /etc/sysconfig/console
491FONT="LatArCyrHeb-16 -m 8859-15"
493# End /etc/sysconfig/console</literal>
495 </listitem>
497 <listitem>
498 <para>Some keymaps have dead keys (i.e., keys that don't produce a
499 character by themselves, but put an accent on the character produced
500 by the next key) or define composition rules (such as: <quote>press
501 Ctrl+. A E to get &AElig;</quote> in the default keymap).
502 Linux-&linux-version; interprets dead keys and composition rules in the
503 keymap correctly only when the source characters to be composed together
504 are not multibyte. This deficiency doesn't affect keymaps for European
505 languages, because there accents are added to unaccented ASCII
506 characters, or two ASCII characters are composed together. However, in
507 UTF-8 mode it is a problem; e.g., for the Greek language, where one
508 sometimes needs to put an accent on the letter <quote>alpha</quote>.
509 The solution is either to avoid the use of UTF-8, or to install the
510 X window system that doesn't have this limitation in its input
511 handling.</para>
512 </listitem>
514 <listitem>
515 <para>For Chinese, Japanese, Korean, and some other languages, the Linux
516 console cannot be configured to display the needed characters. Users
517 who need such languages should install the X Window System, fonts that
518 cover the necessary character ranges, and the proper input method (e.g.,
519 SCIM, supports a wide variety of languages).</para>
520 </listitem>
522 </itemizedlist>
524 <!-- Added because folks keep posting their console file with X questions
525 to blfs-support list -->
526 <note>
527 <para>The <filename>/etc/sysconfig/console</filename> file only controls
528 the Linux text console localization. It has nothing to do with setting
529 the proper keyboard layout and terminal fonts in the X Window System, with
530 ssh sessions, or with a serial console. In such situations, limitations
531 mentioned in the last two list items above do not apply.</para>
532 </note>
534 </sect2>
536 <sect2 id="ch-config-createfiles">
537 <title>Creating Files at Boot</title>
539 <indexterm zone="ch-config-createfiles">
540 <primary sortas="d-createfiles">File creation at boot</primary>
541 <secondary>configuring</secondary>
542 </indexterm>
544 <para>At times, it is desirable to create files at boot time. For instance,
545 the <filename class="directory">/tmp/.ICE-unix</filename> directory
546 is often needed. This can be done by creating an entry in the
547 <filename>/etc/sysconfig/createfiles</filename> configuration script.
548 The format of this file is embedded in the comments of the default
549 configuration file.</para>
550 </sect2>
552 <sect2 id="ch-config-sysklogd">
553 <title>Configuring the sysklogd Script</title>
555 <indexterm zone="ch-config-sysklogd">
556 <primary sortas="d-sysklogd">sysklogd</primary>
557 <secondary>configuring</secondary>
558 </indexterm>
560 <para>The <filename>sysklogd</filename> script invokes the
561 <command>syslogd</command> program as a part of System V initialization. The
562 <parameter>-m 0</parameter> option turns off the periodic timestamp mark that
563 <command>syslogd</command> writes to the log files every 20 minutes by
564 default. If you want to turn on this periodic timestamp mark, edit
565 <filename>/etc/sysconfig/</filename> and define the variable
566 SYSKLOGD_PARMS to the desired value. For instance, to remove all parameters,
567 set the variable to a null value:</para>
569<screen role="nodump">SYSKLOGD_PARMS=</screen>
571 <para>See <userinput>man syslogd</userinput> for more options.</para>
573 </sect2>
575 <sect2 id="ch-config-site">
576 <title>The File</title>
578 <indexterm zone="ch-config-site">
579 <primary sortas=""></primary>
580 </indexterm>
582 <para>The optional <filename>/etc/sysconfig/</filename> file contains
583 settings that are automatically set for each SystemV boot script. It can
584 alternatively set the values specified in the <filename>hostname</filename>,
585 <filename>console</filename>, and <filename>clock</filename> files in the
586 <filename class='directory'>/etc/sysconfig/</filename> directory. If the
587 associated variables are present in both these separate files and
588 <filename></filename>, the values in the script specific files have
589 precedence. </para>
591 <para><filename></filename> also contains parameters that can
592 customize other aspects of the boot process. Setting the IPROMPT variable
593 will enable selective running of bootscripts. Other options are described
594 in the file comments. The default version of the file is as follows:</para>
596 <!-- Use role to fix a pdf generation problem -->
597 <screen role="auto">&site;</screen>
599 <sect3>
600 <title>Customizing the Boot and Shutdown Scripts</title>
602 <para>The LFS boot scripts boot and shut down a system in a fairly
603 efficient manner, but there are a few tweaks that you can make in the
604 file to improve speed even more and to adjust messages according
605 to your preferences. To do this, adjust the settings in
606 the <filename>/etc/sysconfig/</filename> file above.</para>
608 <itemizedlist>
610 <listitem><para>During the boot script <filename>udev</filename>, there is
611 a call to <command>udev settle</command> that requires some time to
612 complete. This time may or may not be required depending on devices present
613 in the system. If you only have simple partitions and a single ethernet
614 card, the boot process will probably not need to wait for this command. To
615 skip it, set the variable OMIT_UDEV_SETTLE=y.</para></listitem>
617 <listitem><para>The boot script <filename>udev_retry</filename> also runs
618 <command>udev settle</command> by default. This command is only needed by
619 default if the <filename class='directory'>/var</filename> directory is
620 separately mounted. This is because the clock needs the file
621 <filename>/var/lib/hwclock/adjtime</filename>. Other customizations may
622 also need to wait for udev to complete, but in many installations it is not
623 needed. Skip the command by setting the variable OMIT_UDEV_RETRY_SETTLE=y.
624 </para></listitem>
626 <listitem><para>By default, the file system checks are silent. This can
627 appear to be a delay during the bootup process. To turn on the
628 <command>fsck</command> output, set the variable VERBOSE_FSCK=y.
629 </para></listitem>
631 <listitem><para>When rebooting, you may want to skip the filesystem check,
632 <command>fsck</command>, completely. To do this, either create the file
633 <filename>/fastboot</filename> or reboot the system with the command
634 <command>/sbin/shutdown -f -r now</command>. On the other hand, you can
635 force all file systems to be checked by creating
636 <filename>/forcefsck</filename> or running <command>shutdown</command> with
637 the <parameter>-F</parameter> parameter instead of <parameter>-f</parameter>.
638 </para>
640 <para>Setting the variable FASTBOOT=y will disable <command>fsck</command>
641 during the boot process until it is removed. This is not recommended
642 on a permanent basis.</para></listitem>
644 <listitem><para>Normally, all files in the <filename
645 class='directory'>/tmp</filename> directory are deleted at boot time.
646 Depending on the number of files or directories present, this can cause a
647 noticeable delay in the boot process. To skip removing these files set the
648 variable SKIPTMPCLEAN=y.</para></listitem>
650 <listitem><para>During shutdown, the <command>init</command> program sends
651 a TERM signal to each program it has started (e.g. agetty), waits for a set
652 time (default 3 seconds), and sends each process a KILL signal and waits
653 again. This process is repeated in the <command>sendsignals</command>
654 script for any processes that are not shut down by their own scripts. The
655 delay for <command>init</command> can be set by passing a parameter. For
656 example to remove the delay in <command>init</command>, pass the -t0
657 parameter when shutting down or rebooting (e.g. <command>/sbin/shutdown
658 -t0 -r now</command>). The delay for the <command>sendsignals</command>
659 script can be skipped by setting the parameter
660 KILLDELAY=0.</para></listitem>
662 </itemizedlist>
664 </sect3>
665 </sect2>
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