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author | Bruce Dubbs <bdubbs@linuxfromscratch.org> | 2020-06-07 20:16:00 +0000 |
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committer | Bruce Dubbs <bdubbs@linuxfromscratch.org> | 2020-06-07 20:16:00 +0000 |
commit | fcc027677da55c41dcaea045f5b9ff8b088e6495 (patch) | |
tree | 42500a7858959695b971e7f28f1d0bf33185db2e /chapter09/network.xml | |
parent | d53fefab5a6772fef606392a61608fc290e6a7ae (diff) |
Initial commit of alternative cross LFS
git-svn-id: http://svn.linuxfromscratch.org/LFS/branches/cross2@11897 4aa44e1e-78dd-0310-a6d2-fbcd4c07a689
Diffstat (limited to 'chapter09/network.xml')
-rw-r--r-- | chapter09/network.xml | 247 |
1 files changed, 247 insertions, 0 deletions
diff --git a/chapter09/network.xml b/chapter09/network.xml new file mode 100644 index 000000000..b527258ee --- /dev/null +++ b/chapter09/network.xml @@ -0,0 +1,247 @@ +<?xml version="1.0" encoding="ISO-8859-1"?> +<!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="ch-config-network" revision="sysv"> + <?dbhtml filename="network.html"?> + + <title>General Network Configuration</title> + + <indexterm zone="ch-config-network"> + <primary sortas="d-network">network</primary> + <secondary>configuring</secondary></indexterm> +<!-- + <para>This section only applies if a network card is to be + configured.</para> + + <para>If a network card will not be used, there is likely no need to create + any configuration files relating to network cards. If that is the case, you + will need to remove the <filename class="symlink">network</filename> symlinks + from all run-level directories (<filename + class="directory">/etc/rc.d/rc*.d</filename>) after the bootscripts are + installed in <xref linkend="ch-config-bootscripts"/>.</para> +--> + <sect2> + <title>Creating Network Interface Configuration Files</title> + + <para>Which interfaces are brought up and down by the network script + usually depends on the files in <filename + class="directory">/etc/sysconfig/</filename>. This directory should + contain a file for each interface to be configured, such as + <filename>ifconfig.xyz</filename>, where <quote>xyz</quote> should describe + the network card. The interface name (e.g. eth0) is usually appropriate. + Inside this file are attributes to this interface, such as its IP + address(es), subnet masks, and so forth. It is necessary that the stem of + the filename be <emphasis>ifconfig</emphasis>.</para> + + <note><para>If the procedure in the previous section was not used, Udev + will assign network card interface names based on system physical + characteristics such as enp2s1. If you are not sure what your interface + name is, you can always run <command>ip link</command> or <command>ls + /sys/class/net</command> after you have booted your system. + </para></note> + + <para>The following command creates a sample file for the + <emphasis>eth0</emphasis> device with a static IP address:</para> +<!-- jhalfs relies on the values for IFACE, IP, etc. If you want to change + them, please inform the jhalfs maintainer(s). --> +<screen><userinput>cd /etc/sysconfig/ +cat > ifconfig.<replaceable>eth0</replaceable> << "EOF" +<literal>ONBOOT=<replaceable>yes</replaceable> +IFACE=<replaceable>eth0</replaceable> +SERVICE=<replaceable>ipv4-static</replaceable> +IP=<replaceable>192.168.1.2</replaceable> +GATEWAY=<replaceable>192.168.1.1</replaceable> +PREFIX=<replaceable>24</replaceable> +BROADCAST=<replaceable>192.168.1.255</replaceable></literal> +EOF</userinput></screen> + + <para>The values in italics must be changed in every file to match + the proper setup.</para> + + <para>If the <envar>ONBOOT</envar> variable is set to <quote>yes</quote> the + System V network script will bring up the Network Interface Card (NIC) during + booting of the system. If set to anything but <quote>yes</quote> the NIC + will be ignored by the network script and not be automatically brought up. + The interface can be manually started or stopped with the + <command>ifup</command> and <command>ifdown</command> commands.</para> + + <para>The <envar>IFACE</envar> variable defines the interface name, + for example, eth0. It is required for all network device configuration + files. The filename extension must match this value.</para> + + <para>The <envar>SERVICE</envar> variable defines the method used for + obtaining the IP address. The LFS-Bootscripts package has a modular IP + assignment format, and creating additional files in the <filename + class="directory">/lib/services/</filename> directory allows other IP + assignment methods. This is commonly used for Dynamic Host Configuration + Protocol (DHCP), which is addressed in the BLFS book.</para> + + <para>The <envar>GATEWAY</envar> variable should contain the default + gateway IP address, if one is present. If not, then comment out the + variable entirely.</para> + + <para>The <envar>PREFIX</envar> variable contains the number of + bits used in the subnet. Each octet in an IP address is 8 bits. If the + subnet's netmask is 255.255.255.0, then it is using the first three octets + (24 bits) to specify the network number. If the netmask is 255.255.255.240, + it would be using the first 28 bits. Prefixes longer than 24 bits are + commonly used by DSL and cable-based Internet Service Providers (ISPs). + In this example (PREFIX=24), the netmask is 255.255.255.0. Adjust the + <envar>PREFIX</envar> variable according to your specific subnet. + If omitted, the PREFIX defaults to 24.</para> + + <para>For more information see the <command>ifup</command> man page.</para> + + </sect2> + <sect2 id="resolv.conf"> + <title>Creating the /etc/resolv.conf File</title> + + <indexterm zone="resolv.conf"> + <primary sortas="e-/etc/resolv.conf">/etc/resolv.conf</primary> + </indexterm> + + <para>The system will need some means of obtaining Domain Name Service + (DNS) name resolution to resolve Internet domain names to IP addresses, and + vice versa. This is best achieved by placing the IP address of the DNS + server, available from the ISP or network administrator, into + <filename>/etc/resolv.conf</filename>. Create the file by running the + following:</para> + +<screen><userinput>cat > /etc/resolv.conf << "EOF" +<literal># Begin /etc/resolv.conf + +domain <replaceable><Your Domain Name></replaceable> +nameserver <replaceable><IP address of your primary nameserver></replaceable> +nameserver <replaceable><IP address of your secondary nameserver></replaceable> + +# End /etc/resolv.conf</literal> +EOF</userinput></screen> + + <para>The <varname>domain</varname> statement can be omitted + or replaced with a <varname>search</varname> statement. See the man page for + resolv.conf for more details.</para> + + <para>Replace <replaceable><IP address of the nameserver></replaceable> + with the IP address of the DNS most appropriate for the setup. There will + often be more than one entry (requirements demand secondary servers for + fallback capability). If you only need or want one DNS server, remove the + second <emphasis>nameserver</emphasis> line from the file. The IP address + may also be a router on the local network.</para> + + <note> + <para>The Google Public IPv4 DNS addresses are 8.8.8.8 and 8.8.4.4.</para> + </note> + + </sect2> + + <sect2 id="ch-config-hostname"> + <title>Configuring the system hostname</title> + + <indexterm zone="ch-config-hostname"> + <primary sortas="d-hostname">hostname</primary> + <secondary>configuring</secondary> + </indexterm> + + <para>During the boot process, the file <filename>/etc/hostname</filename> + is used for establishing the system's hostname.</para> + + <para>Create the <filename>/etc/hostname</filename> file and enter a + hostname by running:</para> + +<screen><userinput>echo "<replaceable><lfs></replaceable>" > /etc/hostname</userinput></screen> + + <para><replaceable><lfs></replaceable> needs to be replaced with the + name given to the computer. Do not enter the Fully Qualified Domain Name + (FQDN) here. That information is put in the + <filename>/etc/hosts</filename> file.</para> + + </sect2> + + <sect2 id="ch-config-hosts"> + <title>Customizing the /etc/hosts File</title> + + <indexterm zone="ch-config-hosts"> + <primary sortas="e-/etc/hosts">/etc/hosts</primary> + </indexterm> + + <indexterm zone="ch-config-hosts"> + <primary sortas="d-localnet">localnet</primary> + <secondary>/etc/hosts</secondary> + </indexterm> + + <indexterm zone="ch-config-hosts"> + <primary sortas="d-network">network</primary> + <secondary>/etc/hosts</secondary> + </indexterm> + + <para>Decide on the IP address, fully-qualified domain name (FQDN), and + possible aliases for use in the <filename>/etc/hosts</filename> file. The + syntax is:</para> + +<screen><literal>IP_address myhost.example.org aliases</literal></screen> + + <para>Unless the computer is to be visible to the Internet (i.e., there is + a registered domain and a valid block of assigned IP addresses—most + users do not have this), make sure that the IP address is in the private + network IP address range. Valid ranges are:</para> + +<screen><literal>Private Network Address Range Normal Prefix +10.0.0.1 - 10.255.255.254 8 +172.x.0.1 - 172.x.255.254 16 +192.168.y.1 - 192.168.y.254 24</literal></screen> + + <para>x can be any number in the range 16-31. y can be any number in the + range 0-255.</para> + + <para>A valid private IP address could be 192.168.1.1. A valid FQDN for + this IP could be lfs.example.org.</para> + + <para>Even if not using a network card, a valid FQDN is still required. + This is necessary for certain programs to operate correctly.</para> + + <para>Create the <filename>/etc/hosts</filename> file by running:</para> + +<screen><userinput>cat > /etc/hosts << "EOF" +<literal># Begin /etc/hosts + +127.0.0.1 localhost.localdomain localhost +127.0.1.1 <replaceable><FQDN></replaceable> <replaceable><HOSTNAME></replaceable> +<replaceable><192.168.1.1></replaceable> <replaceable><FQDN></replaceable> <replaceable><HOSTNAME></replaceable> <replaceable>[alias1] [alias2 ...]</replaceable> +::1 localhost ip6-localhost ip6-loopback +ff02::1 ip6-allnodes +ff02::2 ip6-allrouters + +# End /etc/hosts</literal> +EOF</userinput></screen> + + <para>The <replaceable><192.168.1.1></replaceable>, + <replaceable><FQDN></replaceable>, and + <replaceable><HOSTNAME></replaceable> values need to be + changed for specific uses or requirements (if assigned an IP address by a + network/system administrator and the machine will be connected to an + existing network). The optional alias name(s) can be omitted.</para> + +<!-- This is not very useful + + <para>If a network card is not going to be configured, create the + <filename>/etc/hosts</filename> file by running:</para> + +<screen role="nodump"><userinput>cat > /etc/hosts << "EOF" +<literal># Begin /etc/hosts (no network card version) + +127.0.0.1 localhost +127.0.1.1 <replaceable><FQDN></replaceable> <replaceable><HOSTNAME></replaceable> +::1 localhost ip6-localhost ip6-loopback +ff02::1 ip6-allnodes +ff02::2 ip6-allrouters + +# End /etc/hosts (no network card version)</literal> +EOF</userinput></screen> --> + + </sect2> + +</sect1> |