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<!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">
  %general-entities;
]>

<sect1 id="postlfs-config-random" xreflabel="Random number generation">
  <?dbhtml filename="random.html"?>

  <sect1info>
    <othername>$LastChangedBy: randy $</othername>
    <date>$Date: 2007-04-04 15:42:53 -0400 (Wed, 04 Apr 2007) $</date>
  </sect1info>

  <title>Random Number Generation</title>

  <indexterm zone="postlfs-config-random">
    <primary sortas="f-random">random</primary>
  </indexterm>

  <para>The Linux kernel supplies a random number generator which is accessed
  through <filename class="devicefile">/dev/random</filename> and
  <filename class="devicefile">/dev/urandom</filename>.  Programs that utilize
  the random and urandom devices, such as <application>OpenSSH</application>,
  will benefit from these instructions.</para>

  <para>When a Linux system starts up without much operator interaction, the
  entropy pool (data used to compute a random number) may be in a fairly
  predictable state.  This creates the real possibility that the number generated
  at startup may always be the same.  In order to counteract this effect,
  you should carry the entropy pool information across your shut-downs and
  start-ups.</para>

  <para>Install the <filename>/etc/rc.d/init.d/random</filename> init script
  included with the <xref linkend="bootscripts"/> package.</para>

<screen role="root"><userinput>make install-random</userinput></screen>

</sect1>
