lfs-book/chapter07/hosts.xml

<sect1 id="ch09-hosts">
<title>Creating the /etc/hosts file</title>

<para>
If you want to configure a network card, you have to decide on the
IP-address, FQDN and possible aliases for use in the /etc/hosts file. An
example is:
</para>

<blockquote><literallayout>

	&lt;my-IP&gt; myhost.mydomain.org aliases

</literallayout></blockquote>

<para>
Make sure the IP-address is in the private network IP-address range.
Valid ranges are:
</para>

<blockquote><literallayout>

	Class Networks
	A     10.0.0.0
	B     172.16.0.0 through 172.31.0.0
	C     192.168.0.0 through 192.168.255.0

</literallayout></blockquote>

<para>
A valid IP address could be 192.168.1.1. A valid FQDN for this IP could
be www.linuxfromscratch.org
</para>

<para>
If you're not going to use a network card, you still need to come up with a
FQDN. This is necessary for programs like Sendmail to operate correctly (in
fact; Sendmail won't run when it can't determine the FQDN).
</para>

<para>
If you don't configure a network card, create a new file
<filename>/etc/hosts</filename> by running:
</para>

<literallayout>

<userinput>cat &gt; /etc/hosts &lt;&lt; "EOF"</userinput>
# Begin /etc/hosts (no network card version)

127.0.0.1 www.mydomain.com &lt;value of HOSTNAME&gt; localhost

# End /etc/hosts (no network card version)
<userinput>EOF</userinput>

</literallayout>

<para>
If you do configure a network card, create a new file
<filename>/etc/hosts</filename> containing:
</para>

<literallayout>

<userinput>cat &gt; /etc/hosts &lt;&lt; "EOF"</userinput>
# Begin /etc/hosts (network card version)

127.0.0.1 localhost.localdomain localhost
192.168.1.1 www.mydomain.org &lt;value of HOSTNAME&gt;

# End /etc/hosts (network card version)
<userinput>EOF</userinput>

</literallayout>

<para>
Of course, change the 192.168.1.1 and www.mydomain.org to your own
liking (or requirements if you are assigned an IP-address by a network/system
administrator and you plan on connecting this machine to that network).
</para>

</sect1>