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diff --git a/chapter07/usage.xml b/chapter07/usage.xml index 3250cd328..3eb323a6e 100644 --- a/chapter07/usage.xml +++ b/chapter07/usage.xml @@ -2,32 +2,36 @@ <!DOCTYPE sect1 PUBLIC "-//OASIS//DTD DocBook XML V4.5//EN" "http://www.oasis-open.org/docbook/xml/4.5/docbookx.dtd" [ <!ENTITY % general-entities SYSTEM "../general.ent"> + <!ENTITY site SYSTEM "../appendices/rc.site.script"> %general-entities; ]> <sect1 id="ch-scripts-usage"> <?dbhtml filename="usage.html"?> - <title>How Do the System V Bootscripts Work?</title> + <title>System V Bootscript Usage and Configuration</title> <indexterm zone="ch-scripts-usage"> <primary sortas="a-Bootscripts">Bootscripts</primary> <secondary>usage</secondary> </indexterm> - <para>Linux uses a special booting facility named SysVinit that is based on a - concept of <emphasis>run-levels</emphasis>. It can be quite different from one - system to another, so it cannot be assumed that because things worked in one - particular Linux distribution, they should work the same in LFS too. LFS has its - own way of doing things, but it respects generally accepted standards.</para> - - <para>SysVinit (which will be referred to as <quote>init</quote> from now on) - works using a run-levels scheme. There are seven (numbered 0 to 6) run-levels - (actually, there are more run-levels, but they are for special cases and are - generally not used. See <filename>init(8)</filename> for more details), and - each one of those corresponds to the actions the computer is supposed to - perform when it starts up. The default run-level is 3. Here are the - descriptions of the different run-levels as they are implemented:</para> + <sect2> + <title>How Do the System V Bootscripts Work?</title> + + <para>Linux uses a special booting facility named SysVinit that is based on a + concept of <emphasis>run-levels</emphasis>. It can be quite different from one + system to another, so it cannot be assumed that because things worked in one + particular Linux distribution, they should work the same in LFS too. LFS has its + own way of doing things, but it respects generally accepted standards.</para> + + <para>SysVinit (which will be referred to as <quote>init</quote> from now on) + works using a run-levels scheme. There are seven (numbered 0 to 6) run-levels + (actually, there are more run-levels, but they are for special cases and are + generally not used. See <filename>init(8)</filename> for more details), and + each one of those corresponds to the actions the computer is supposed to + perform when it starts up. The default run-level is 3. Here are the + descriptions of the different run-levels as they are implemented:</para> <literallayout>0: halt the computer 1: single-user mode @@ -37,6 +41,8 @@ 5: same as 4, it is usually used for GUI login (like X's <command>xdm</command> or KDE's <command>kdm</command>) 6: reboot the computer</literallayout> + </sect2> + <sect2 id="conf-sysvinit" role="configuration"> <title>Configuring Sysvinit</title> @@ -106,9 +112,7 @@ EOF</userinput></screen> persistent across boots, however it is appended to the more permanent file <filename>/var/log/boot.log</filename> at the end of the boot process.</para> - </sect2> - - <sect2 id="init-levels" > + <sect3 id="init-levels" > <title>Changing Run Levels</title> <para>Changing run-levels is done with <command>init @@ -200,6 +204,430 @@ EOF</userinput></screen> it is your own LFS system). The files given here are an example of how it can be done.</para> + </sect3> + </sect2> + + <sect2 id="ch-scripts-clock"> + <title>Configuring the System Clock</title> + + <sect3 id="ch-scripts-setclock"> + <title>System V Clock Configuration</title> + + <indexterm zone="ch-scripts-setclock"> + <primary sortas="d-setclock">setclock</primary> + <secondary>configuring</secondary></indexterm> + + <para>The <command>setclock</command> script reads the time from the hardware + clock, also known as the BIOS or the Complementary Metal Oxide Semiconductor + (CMOS) clock. If the hardware clock is set to UTC, this script will convert the + hardware clock's time to the local time using the + <filename>/etc/localtime</filename> file (which tells the + <command>hwclock</command> program which timezone the user is in). There is no + way to detect whether or not the hardware clock is set to UTC, so this + needs to be configured manually.</para> + + <para>The <command>setclock</command> is run via + <application>udev</application> when the kernel detects the hardware + capability upon boot. It can also be run manually with the stop parameter to + store the system time to the CMOS clock.</para> + + <para>If you cannot remember whether or not the hardware clock is set to UTC, + find out by running the <userinput>hwclock --localtime --show</userinput> + command. This will display what the current time is according to the hardware + clock. If this time matches whatever your watch says, then the hardware clock is + set to local time. If the output from <command>hwclock</command> is not local + time, chances are it is set to UTC time. Verify this by adding or subtracting + the proper amount of hours for the timezone to the time shown by + <command>hwclock</command>. For example, if you are currently in the MST + timezone, which is also known as GMT -0700, add seven hours to the local + time.</para> + + <para>Change the value of the <envar>UTC</envar> variable below + to a value of <parameter>0</parameter> (zero) if the hardware clock + is <emphasis>not</emphasis> set to UTC time.</para> + + <para>Create a new file <filename>/etc/sysconfig/clock</filename> by running + the following:</para> + +<screen><userinput>cat > /etc/sysconfig/clock << "EOF" +<literal># Begin /etc/sysconfig/clock + +UTC=1 + +# Set this to any options you might need to give to hwclock, +# such as machine hardware clock type for Alphas. +CLOCKPARAMS= + +# End /etc/sysconfig/clock</literal> +EOF</userinput></screen> + + <para>A good hint explaining how to deal with time on LFS is available + at <ulink url="&hints-root;time.txt"/>. It explains issues such as + time zones, UTC, and the <envar>TZ</envar> environment variable.</para> + + <note><para>The CLOCKPARAMS and UTC paramaters may be alternatively set + in the <filename>/etc/sysconfig/rc.site</filename> file.</para></note> + + </sect3> </sect2> + <sect2 id="ch-scripts-console"> + <?dbhtml filename="console.html"?> + + <title>Configuring the Linux Console</title> + + <indexterm zone="ch-scripts-console"> + <primary sortas="d-console">console</primary> + <secondary>configuring</secondary> + </indexterm> + + <para>This section discusses how to configure the <command>console</command> + bootscript that sets up the keyboard map, console font and console kernel log + level. If non-ASCII characters (e.g., the copyright sign, the British pound + sign and Euro symbol) will not be used and the keyboard is a U.S. one, much + of this section can be skipped. Without the configuration file, (or + equivalent settings in <filename>rc.site</filename>), the + <command>console</command> bootscript will do nothing.</para> + + <para>The <command>console</command> script reads the + <filename>/etc/sysconfig/console</filename> file for configuration + information. Decide which keymap and screen font will be used. Various + language-specific HOWTOs can also help with this, see <ulink + url="http://www.tldp.org/HOWTO/HOWTO-INDEX/other-lang.html"/>. If still in + doubt, look in the <filename class="directory">/usr/share/keymaps</filename> + and <filename class="directory">/usr/share/consolefonts</filename> directories + for valid keymaps and screen fonts. Read <filename>loadkeys(1)</filename> and + <filename>setfont(8)</filename> manual pages to determine the correct + arguments for these programs.</para> + + <para>The <filename>/etc/sysconfig/console</filename> file should contain lines + of the form: VARIABLE="value". The following variables are recognized:</para> + <variablelist> + + <varlistentry> + <term>LOGLEVEL</term> + <listitem> + <para>This variable specifies the log level for kernel messages sent + to the console as set by <command>dmesg</command>. Valid levels are + from "1" (no messages) to "8". The default level is "7".</para> + </listitem> + </varlistentry> + + <varlistentry> + <term>KEYMAP</term> + <listitem> + <para>This variable specifies the arguments for the + <command>loadkeys</command> program, typically, the name of keymap + to load, e.g., <quote>es</quote>. If this variable is not set, the + bootscript will not run the <command>loadkeys</command> program, + and the default kernel keymap will be used.</para> + </listitem> + </varlistentry> + + <varlistentry> + <term>KEYMAP_CORRECTIONS</term> + <listitem> + <para>This (rarely used) variable + specifies the arguments for the second call to the + <command>loadkeys</command> program. This is useful if the stock keymap + is not completely satisfactory and a small adjustment has to be made. E.g., + to include the Euro sign into a keymap that normally doesn't have it, + set this variable to <quote>euro2</quote>.</para> + </listitem> + </varlistentry> + + <varlistentry> + <term>FONT</term> + <listitem> + <para>This variable specifies the arguments for the + <command>setfont</command> program. Typically, this includes the font + name, <quote>-m</quote>, and the name of the application character + map to load. E.g., in order to load the <quote>lat1-16</quote> font + together with the <quote>8859-1</quote> application character map + (as it is appropriate in the USA), + <!-- because of the copyright sign --> + set this variable to <quote>lat1-16 -m 8859-1</quote>. + In UTF-8 mode, the kernel uses the application character map for + conversion of composed 8-bit key codes in the keymap to UTF-8, and thus + the argument of the "-m" parameter should be set to the encoding of the + composed key codes in the keymap.</para> + + </listitem> + </varlistentry> + + <varlistentry> + <term>UNICODE</term> + <listitem> + <para>Set this variable to <quote>1</quote>, <quote>yes</quote> or + <quote>true</quote> in order to put the + console into UTF-8 mode. This is useful in UTF-8 based locales and + harmful otherwise.</para> + </listitem> + </varlistentry> + + <varlistentry> + <term>LEGACY_CHARSET</term> + <listitem> + <para>For many keyboard layouts, there is no stock Unicode keymap in + the Kbd package. The <command>console</command> bootscript will + convert an available keymap to UTF-8 on the fly if this variable is + set to the encoding of the available non-UTF-8 keymap.</para> + </listitem> + </varlistentry> + + </variablelist> + + <para>Some examples:</para> + + <itemizedlist> + + <listitem> + <para>For a non-Unicode setup, only the KEYMAP and FONT variables are + generally needed. E.g., for a Polish setup, one would use:</para> +<screen role="nodump"><userinput>cat > /etc/sysconfig/console << "EOF" +<literal># Begin /etc/sysconfig/console + +KEYMAP="pl2" +FONT="lat2a-16 -m 8859-2" + +# End /etc/sysconfig/console</literal> +EOF</userinput></screen> + </listitem> + + <listitem> + <para>As mentioned above, it is sometimes necessary to adjust a + stock keymap slightly. The following example adds the Euro symbol to the + German keymap:</para> + +<screen role="nodump"><userinput>cat > /etc/sysconfig/console << "EOF" +<literal># Begin /etc/sysconfig/console + +KEYMAP="de-latin1" +KEYMAP_CORRECTIONS="euro2" +FONT="lat0-16 -m 8859-15" + +# End /etc/sysconfig/console</literal> +EOF</userinput></screen> + </listitem> + + <listitem> + <para>The following is a Unicode-enabled example for Bulgarian, where a + stock UTF-8 keymap exists:</para> + +<screen role="nodump"><userinput>cat > /etc/sysconfig/console << "EOF" +<literal># Begin /etc/sysconfig/console + +UNICODE="1" +KEYMAP="bg_bds-utf8" +FONT="LatArCyrHeb-16" + +# End /etc/sysconfig/console</literal> +EOF</userinput></screen> + </listitem> + + <listitem> + <para>Due to the use of a 512-glyph LatArCyrHeb-16 font in the previous + example, bright colors are no longer available on the Linux console unless + a framebuffer is used. If one wants to have bright colors without + framebuffer and can live without characters not belonging to his language, + it is still possible to use a language-specific 256-glyph font, as + illustrated below:</para> + +<screen role="nodump"><userinput>cat > /etc/sysconfig/console << "EOF" +<literal># Begin /etc/sysconfig/console + +UNICODE="1" +KEYMAP="bg_bds-utf8" +FONT="cyr-sun16" + +# End /etc/sysconfig/console</literal> +EOF</userinput></screen> + </listitem> + + <listitem> + <para>The following example illustrates keymap autoconversion from + ISO-8859-15 to UTF-8 and enabling dead keys in Unicode mode:</para> + +<screen role="nodump"><userinput>cat > /etc/sysconfig/console << "EOF" +<literal># Begin /etc/sysconfig/console + +UNICODE="1" +KEYMAP="de-latin1" +KEYMAP_CORRECTIONS="euro2" +LEGACY_CHARSET="iso-8859-15" +FONT="LatArCyrHeb-16 -m 8859-15" + +# End /etc/sysconfig/console</literal> +EOF</userinput></screen> + </listitem> + + <listitem> + <para>Some keymaps have dead keys (i.e., keys that don't produce a + character by themselves, but put an accent on the character produced + by the next key) or define composition rules (such as: <quote>press + Ctrl+. A E to get Æ</quote> in the default keymap). + Linux-&linux-version; interprets dead keys and composition rules in the + keymap correctly only when the source characters to be composed together + are not multibyte. This deficiency doesn't affect keymaps for European + languages, because there accents are added to unaccented ASCII + characters, or two ASCII characters are composed together. However, in + UTF-8 mode it is a problem, e.g., for the Greek language, where one + sometimes needs to put an accent on the letter <quote>alpha</quote>. + The solution is either to avoid the use of UTF-8, or to install the + X window system that doesn't have this limitation in its input + handling.</para> + </listitem> + + <listitem> + <para>For Chinese, Japanese, Korean and some other languages, the Linux + console cannot be configured to display the needed characters. Users + who need such languages should install the X Window System, fonts that + cover the necessary character ranges, and the proper input method (e.g., + SCIM, it supports a wide variety of languages).</para> + </listitem> + + </itemizedlist> + + <!-- Added because folks keep posting their console file with X questions + to blfs-support list --> + <note> + <para>The <filename>/etc/sysconfig/console</filename> file only controls + the Linux text console localization. It has nothing to do with setting + the proper keyboard layout and terminal fonts in the X Window System, with + ssh sessions or with a serial console. In such situations, limitations + mentioned in the last two list items above do not apply.</para> + </note> + + </sect2> + + <sect2 id="ch-scripts-createfiles"> + <title>Creating Files at Boot</title> + + <indexterm zone="ch-scripts-createfiles"> + <primary sortas="d-createfiles">File creation at boot</primary> + <secondary>configuring</secondary> + </indexterm> + + <para>At times, it is desired to create files at boot time. For instance, + the <filename class="directory">/tmp/.ICE-unix</filename> directory + may be desired. This can be done by creating an entry in the + <filename>/etc/sysconfig/createfiles</filename> configuration script. + The format of this file is embedded in the comments of the default + configuration file.</para> + </sect2> + + <sect2 id="ch-scripts-sysklogd"> + <title>Configuring the sysklogd Script</title> + + <indexterm zone="ch-scripts-sysklogd"> + <primary sortas="d-sysklogd">sysklogd</primary> + <secondary>configuring</secondary> + </indexterm> + + <para>The <filename>sysklogd</filename> script invokes the + <command>syslogd</command> program as a part of System V initialization. The + <parameter>-m 0</parameter> option turns off the periodic timestamp mark that + <command>syslogd</command> writes to the log files every 20 minutes by + default. If you want to turn on this periodic timestamp mark, edit + <filename>/etc/sysconfig/rc.site</filename> and define the variable + SYSKLOGD_PARMS to the desired value. For instance, to remove all parameters, + set the variable to a null value:</para> + +<screen role="nodump">SYSKLOGD_PARMS=</screen> + + <para>See <userinput>man syslogd</userinput> for more options.</para> + + </sect2> + + <sect2 id="ch-scripts-site"> + <title>The rc.site File</title> + + <indexterm zone="ch-scripts-site"> + <primary sortas="a-rc.site">rc.site</primary> + </indexterm> + + <para>The optional <filename>/etc/sysconfig/rc.site</filename> file contains + settings that are automatically set for each SystemV boot script. It can + alternatively set the values specified in the <filename>hostname</filename>, + <filename>console</filename>, and <filename>clock</filename> files in the + <filename class='directory'>/etc/sysconfig/</filename> directory. If the + associated variables are present in both these separate files and + <filename>rc.site</filename>, the values in the script specific files have + precedence. </para> + + <para><filename>rc.site</filename> also contains parameters that can + customize other aspects of the boot process. Setting the IPROMPT variable + will enable selective running of bootscripts. Other options are described + in the file comments. The default version of the file is as follows:</para> + + <!-- Use role to fix a pdf generation problem --> + <screen role="auto">&site;</screen> + + <sect3> + <title>Customizing the Boot and Shutdown Scripts</title> + + <para>The LFS boot scripts boot and shut down a system in a fairly + efficient manner, but there are a few tweaks that you can make in the + rc.site file to improve speed even more and to adjust messages according + to your preferences. To do this, adjust the settings in + the <filename>/etc/sysconfig/rc.site</filename> file above.</para> + + <itemizedlist> + + <listitem><para>During the boot script <filename>udev</filename>, there is + a call to <command>udev settle</command> that requires some time to + complete. This time may or may not be required depending on devices present + in the system. If you only have simple partitions and a single ethernet + card, the boot process will probably not need to wait for this command. To + skip it, set the variable OMIT_UDEV_SETTLE=y.</para></listitem> + + <listitem><para>The boot script <filename>udev_retry</filename> also runs + <command>udev settle</command> by default. This command is only needed by + default if the <filename class='directory'>/var</filename> directory is + separately mounted. This is because the clock needs the file + <filename>/var/lib/hwclock/adjtime</filename>. Other customizations may + also need to wait for udev to complete, but in many installations it is not + needed. Skip the command by setting the variable OMIT_UDEV_RETRY_SETTLE=y. + </para></listitem> + + <listitem><para>By default, the file system checks are silent. This can + appear to be a delay during the bootup process. To turn on the + <command>fsck</command> output, set the variable VERBOSE_FSCK=y. + </para></listitem> + + <listitem><para>When rebooting, you may want to skip the filesystem check, + <command>fsck</command>, completely. To do this, either create the file + <filename>/fastboot</filename> or reboot the system with the command + <command>/sbin/shutdown -f -r now</command>. On the other hand, you can + force all file systems to be checked by creating + <filename>/forcefsck</filename> or running <command>shutdown</command> with + the <parameter>-F</parameter> parameter instead of <parameter>-f</parameter>. + </para> + + <para>Setting the variable FASTBOOT=y will disable <command>fsck</command> + during the boot process until it is removed. This is not recommended + on a permanent basis.</para></listitem> + + <listitem><para>Normally, all files in the <filename + class='directory'>/tmp</filename> directory are deleted at boot time. + Depending on the number of files or directories present, this can cause a + noticeable delay in the boot process. To skip removing these files set the + variable SKIPTMPCLEAN=y.</para></listitem> + + <listitem><para>During shutdown, the <command>init</command> program sends + a TERM signal to each program it has started (e.g. agetty), waits for a set + time (default 3 seconds), and sends each process a KILL signal and waits + again. This process is repeated in the <command>sendsignals</command> + script for any processes that are not shut down by their own scripts. The + delay for <command>init</command> can be set by passing a parameter. For + example to remove the delay in <command>init</command>, pass the -t0 + parameter when shutting down or rebooting (e.g. <command>/sbin/shutdown + -t0 -r now</command>). The delay for the <command>sendsignals</command> + script can be skipped by setting the parameter + KILLDELAY=0.</para></listitem> + + </itemizedlist> + + </sect3> + </sect2> </sect1> |