| 1 | <?xml version="1.0" encoding="ISO-8859-1"?>
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| 2 | <!DOCTYPE sect1 PUBLIC "-//OASIS//DTD DocBook XML V4.4//EN"
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| 3 |   "http://www.oasis-open.org/docbook/xml/4.4/docbookx.dtd" [
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| 4 |   <!ENTITY % general-entities SYSTEM "../../general.ent">
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| 5 |   %general-entities;
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| 6 | ]>
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| 7 | 
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| 8 | <sect1 id="ch-scripts-hosts">
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| 9 |   <?dbhtml filename="hosts.html"?>
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| 10 | 
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| 11 |   <title>Creating the /etc/hosts File</title>
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| 12 | 
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| 13 |   <indexterm zone="ch-scripts-hosts">
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| 14 |     <primary sortas="e-/etc/hosts">/etc/hosts</primary>
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| 15 |   </indexterm>
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| 16 | 
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| 17 |   <indexterm zone="ch-scripts-hosts">
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| 18 |     <primary sortas="d-localnet">localnet</primary>
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| 19 |   <secondary>/etc/hosts</secondary></indexterm>
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| 20 | 
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| 21 |   <indexterm zone="ch-scripts-hosts">
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| 22 |     <primary sortas="d-network">network</primary>
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| 23 |   <secondary>/etc/hosts</secondary></indexterm>
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| 24 | 
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| 25 |   <para>If a network card is to be configured, decide on the IP address,
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| 26 |   FQDN, and possible aliases for use in the
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| 27 |   <filename>/etc/hosts</filename> file. The syntax is:</para>
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| 28 | 
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| 29 |   <screen><IP address> myhost.example.org aliases</screen>
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| 30 | 
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| 31 |   <para>Unless the computer is to be visible to the Internet (i.e.,
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| 32 |   there is a registered domain and a valid block of assigned IP
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| 33 |   addresses—most users do not have this), make sure that the IP
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| 34 |   address is in the private network IP address range. Valid ranges
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| 35 |   are:</para>
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| 36 | 
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| 37 | <screen><literal>  Class Networks
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| 38 |   A     10.0.0.0
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| 39 |   B     172.16.0.0 through 172.31.0.255
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| 40 |   C     192.168.0.0 through 192.168.255.255</literal></screen>
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| 41 | 
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| 42 |   <para>A valid IP address could be 192.168.1.1. A valid FQDN for this
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| 43 |   IP could be <uri>www.linuxfromscratch.org</uri> (not recommended
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| 44 |   because this is a valid registered domain address and could cause
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| 45 |   domain name server issues).</para>
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| 46 | 
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| 47 |   <para>Even if not using a network card, an FQDN is still required.
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| 48 |   This is necessary for certain programs to operate correctly.</para>
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| 49 | 
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| 50 |   <para>Create the  <filename>/etc/hosts</filename> file by running:</para>
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| 51 | 
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| 52 | <screen><userinput>cat > /etc/hosts << "EOF"
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| 53 | <literal># Begin /etc/hosts (network card version)
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| 54 | 
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| 55 | 127.0.0.1 localhost
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| 56 | <replaceable>[192.168.1.1]</replaceable> <replaceable>[<HOSTNAME>.example.org]</replaceable> <replaceable>[HOSTNAME]</replaceable>
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| 57 | 
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| 58 | # End /etc/hosts (network card version)</literal>
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| 59 | EOF</userinput></screen>
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| 60 | 
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| 61 |   <para>The <replaceable>[192.168.1.1]</replaceable> and
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| 62 |   <replaceable>[<HOSTNAME>.example.org]</replaceable>
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| 63 |   values need to be changed for specific users or requirements (if
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| 64 |   assigned an IP address by a network/system administrator and the
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| 65 |   machine will be connected to an existing network).</para>
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| 66 | 
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| 67 | 
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| 68 |   <para>If a network card is not going to be configured, create the
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| 69 |   <filename>/etc/hosts</filename> file by running:</para>
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| 70 | 
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| 71 | <screen><userinput>cat > /etc/hosts << "EOF"
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| 72 | <literal># Begin /etc/hosts (no network card version)
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| 73 | 
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| 74 | 127.0.0.1 <replaceable>[<HOSTNAME>.example.org]</replaceable> <replaceable>[HOSTNAME]</replaceable> localhost
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| 75 | 
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| 76 | # End /etc/hosts (no network card version)</literal>
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| 77 | EOF</userinput></screen>
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| 78 | 
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| 79 | </sect1>
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