2004-06-10 12:31:35 +08:00
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<?xml version="1.0" encoding="ISO-8859-1"?>
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2005-04-04 04:52:42 +08:00
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<!DOCTYPE sect1 PUBLIC "-//OASIS//DTD DocBook XML V4.4//EN"
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"http://www.oasis-open.org/docbook/xml/4.4/docbookx.dtd" [
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2004-06-10 12:31:35 +08:00
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<!ENTITY % general-entities SYSTEM "../../general.ent">
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%general-entities;
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]>
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2005-01-15 08:30:04 +08:00
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<sect1 id="postlfs-config-random" xreflabel="Random number generation">
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2005-05-13 05:17:08 +08:00
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<?dbhtml filename="random.html"?>
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<sect1info>
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<othername>$LastChangedBy$</othername>
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<date>$Date$</date>
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</sect1info>
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<title>Random Number Generation</title>
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<indexterm zone="postlfs-config-random">
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<primary sortas="f-random">random</primary>
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</indexterm>
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<para>The Linux kernel supplies a random number generator which is accessed
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2005-05-31 05:56:30 +08:00
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through <filename class="devicefile">/dev/random</filename> and
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<filename class="devicefile">/dev/urandom</filename>. Programs that utilize
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the random and urandom devices, such as <application>OpenSSH</application>,
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2005-05-13 05:17:08 +08:00
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will benefit from these instructions.</para>
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<para>When a Linux system starts up without much operator interaction, the
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2005-07-23 06:59:56 +08:00
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entropy pool (data used to compute a random number) may be in a fairly
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2005-05-13 05:17:08 +08:00
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predictable state. This creates the real possibility that the number generated
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at startup may always be the same. In order to counteract this effect,
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you should carry the entropy pool information across your shut-downs and
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start-ups.</para>
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2005-05-31 05:56:30 +08:00
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<para>Install the <filename>/etc/rc.d/init.d/random</filename> init script
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2005-05-13 05:17:08 +08:00
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included with the <xref linkend="intro-important-bootscripts"/> package.</para>
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<screen role="root"><userinput>make install-random</userinput></screen>
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2002-07-08 04:28:42 +08:00
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</sect1>
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