source: connect/dhcp/dhcp-client.xml@ 246c904

<?xml version="1.0" encoding="ISO-8859-1"?>
<!DOCTYPE sect1 PUBLIC "-//OASIS//DTD DocBook XML V4.3//EN"
   "http://www.oasis-open.org/docbook/xml/4.3/docbookx.dtd" [
  <!ENTITY % general-entities SYSTEM "../../general.ent">
  %general-entities;
]>

<sect1 id="connect-dhcp-client">
<?dbhtml filename="dhcpclient.html"?>
<title>DHCP-&dhcp-version;</title>

<para>The <application><acronym>DHCP</acronym></application> package comes with
both a client (<command>dhclient</command>) and a server program for 
using <acronym>DHCP</acronym>.  If you want to install this package, 
the instructions can be found at <xref linkend="dhcp"/>.  
Note that if you only want to use the client, you 
do <emphasis>not</emphasis> need to run the server and so do not need 
the startup script and links provided for the server daemon.
You only need to run the <acronym>DHCP</acronym> server if you're providing 
this service to a network, and it's likely that you'll know if that's the
case; if it isn't, don't run the server!  Once you have installed the
package, return here for information on how to configure the client
(<command>dhclient</command>).</para>

<para>To configure <command>dhclient</command>, you need to first install 
the network service script,
<filename>/etc/sysconfig/network-devices/services/dhclient</filename> 
included in the <xref linkend="intro-important-bootscripts"/> package.</para>

<screen><userinput><command>make install-service-dhclient</command></userinput></screen>

<para>Next, create the <filename>ifconfig.eth0</filename>
file with the following commands.  Adjust as necessary for additional
interfaces.</para>

<para><emphasis>Note</emphasis>: this will overwrite any existing file.</para>

<screen><userinput><command>cat &gt; /etc/sysconfig/network-devices/ifconfig.eth0 &lt;&lt; "EOF"</command>
ONBOOT=yes
DHCP_START="<replaceable>[place appropriate start parameters here]</replaceable>"
DHCP_STOP="-r <replaceable>[add additional stop parameters here]</replaceable>"
SERVICE=dhclient
<command>EOF</command></userinput></screen>

<para>For more information on the appropriate 
<envar>DHCP_START</envar> and <envar>DHCP_STOP</envar> 
values, examine the man page for <command>dhclient</command>.</para>

<para> You should then create 
<filename>/etc/dhclient.conf</filename> using the following
commands.  Append to the file if you have more than one interface:</para>

<screen><userinput><command>cat &gt; /etc/dhclient.conf &lt;&lt; "EOF"</command>
# dhclient.conf

interface "eth0"{
prepend domain-name-servers 127.0.0.1;
request subnet-mask, broadcast-address, time-offset, routers,
        domain-name, domain-name-servers, host-name;
require subnet-mask, domain-name-servers;
}
# end dhclient.conf
<command>EOF</command></userinput></screen>

<para>Finally, if the <acronym>DHCP</acronym> configured interface is
used as your default gateway, you should remove the GATEWAY and GATEWAY_IF 
variables from <filename>/etc/sysconfig/network</filename>: </para>

<screen><userinput><command>sed -i "s/GATEWAY/#GATEWAY/" /etc/sysconfig/network</command></userinput></screen>

</sect1>