source: networking/netprogs/bridgeutils.xml

<?xml version="1.0" encoding="UTF-8"?>
<!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;

  <!ENTITY bridge-download-http "&kernel-dl;/linux/utils/net/bridge-utils/bridge-utils-&bridgeutils-version;.tar.xz">
  <!ENTITY bridge-download-ftp  " ">
  <!ENTITY bridge-md5sum        "3e1fee4dc22cac5457c2f6ffb990a518">
  <!ENTITY bridge-size          "29 KB">
  <!ENTITY bridge-buildsize     "1.1 MB">
  <!ENTITY bridge-time          "less than 0.1 SBU">
]>

<sect1 id="bridgeutils" xreflabel="bridge-utils-&bridgeutils-version;">
  <?dbhtml filename="bridge-utils.html"?>


  <title>bridge-utils-&bridgeutils-version;</title>

  <indexterm zone="bridgeutils">
    <primary sortas="a-bridgeutils">bridge-utils</primary>
  </indexterm>

  <sect2 role="package">
    <title>Introduction to bridge-utils</title>

    <para>
      The <application>bridge-utils</application> package contains a utility
      needed to create and manage bridge devices.  This is useful in setting up
      networks for a hosted virtual machine (VM).
    </para>

    &lfs121_checked;

    <bridgehead renderas="sect3">Package Information</bridgehead>
    <itemizedlist spacing="compact">
      <listitem>
        <para>
          Download (HTTP): <ulink url="&bridge-download-http;"/>
        </para>
      </listitem>
      <listitem>
        <para>
          Download (FTP): <ulink url="&bridge-download-ftp;"/>
        </para>
      </listitem>
      <listitem>
        <para>
          Download MD5 sum: &bridge-md5sum;
        </para>
      </listitem>
      <listitem>
        <para>
          Download size: &bridge-size;
        </para>
      </listitem>
      <listitem>
        <para>
          Estimated disk space required: &bridge-buildsize;
        </para>
      </listitem>
      <listitem>
        <para>
          Estimated build time: &bridge-time;
        </para>
      </listitem>
    </itemizedlist>

    <bridgehead renderas="sect3">bridge-utils Dependencies</bridgehead>

    <bridgehead renderas="sect4">Optional (to run tests)</bridgehead>
    <para role="optional">
      <xref linkend="net-tools"/>
    </para>


  </sect2>

  <sect2 role="kernel" id='bridgeutils-kernel'>
    <title>Kernel Configuration</title>

    <para>
      Enable the following options in the kernel configuration
      and recompile the kernel if necessary:
    </para>

    <xi:include xmlns:xi="http://www.w3.org/2001/XInclude"
      href="bridgeutils-kernel.xml"/>

    <indexterm zone="bridgeutils bridgeutils-kernel">
      <primary sortas="d-bridgeutils">Bridge Utilities</primary>
    </indexterm>

  </sect2>

  <sect2 role="installation">
    <title>Installation of bridge-utils</title>

    <para>
      Install <application>bridge-utils</application> by running the following
      commands:
    </para>

<screen><userinput>autoconf                  &amp;&amp;
./configure --prefix=/usr &amp;&amp;
make</userinput></screen>

    <para>
      Testing the results requires running the six shell scripts in
      the <filename class='directory'>tools/</filename> directory.
      Two of the tests require two ethernet ports.  Some tests
      will not preserve the current network configuration.  See
      <filename>tests/README</filename> for details.
    </para>

    <para>
      Now, as the <systemitem class="username">root</systemitem> user:
    </para>

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

  </sect2>

  <sect2 role="configuration" revision="sysv">
    <title>Configuring bridge-utils</title>

    <sect3 id='bridgeutils-init'>
      <title>Configuration Information</title>

      <para>
        To automate bridge creation and configuration,
        install the <filename>/usr/lib/services/bridge</filename>
        service script included in the <xref linkend="bootscripts"/>
        package.
      </para>

      <indexterm zone="bridgeutils bridgeutils-init">
        <primary sortas="f-bridgeutils">bridge-utils</primary>
      </indexterm>

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

      <note>
        <para>
          The <filename>bridge</filename> script depends
          on the commands <command>/sbin/ifup</command> and
          <command>/sbin/ifdown</command> and the service script
          <emphasis>ipv4-static</emphasis> from the <emphasis>LFS</emphasis>
          bootscripts dated January 27, 2012 or later.
        </para>
      </note>

      <para>
        The following configuration file will create a bridge device at
        boot time and attach the eth0 device to it.  If more than one device is
        desired, use a space separated list of INTERFACE_COMPONENTS.  This
        configuration is useful when planning to run a virtual machine such as
        kvm/qemu.
      </para>

      <para>
        Other <envar>SERVICE</envar> combinations are possible, for example,
        <code>SERVICE="bridge dhcp"</code>.  In that case, the address
        parameters are not needed, but do not interfere if present. The
        bridge service may also be used alone, but will require
        additional subsequent configuration.
      </para>

      <caution>
        <para>
          Do not run a parallel configuration for a device in the
          INTERFACE_COMPONENTS list.  For instance, in the example below, do not
          configure <filename>/etc/sysconfig/ifconfig.eth0</filename> to run at
          boot time.  The command <command>ifdown br0</command> followed by
          command <command>ifup eth0</command> will work, but don't try to have
          both up at the same time.
        </para>
      </caution>

<screen role="root"><userinput>cat &gt; /etc/sysconfig/ifconfig.br0 &lt;&lt; "EOF"
<literal>ONBOOT=yes
IFACE=br0
VIRTINT=yes
SERVICE="bridge ipv4-static"  # Space separated
IP=192.168.1.32
GATEWAY=192.168.1.1
PREFIX=24
BROADCAST=192.168.1.255
CHECK_LINK=no                 # Don't check before bridge is created
STP=no                        # Spanning tree protocol, default no
INTERFACE_COMPONENTS="eth0"   # Add to IFACE, space separated devices
IP_FORWARD=true</literal>
EOF</userinput></screen>

      <para>
        All addresses should be changed to meet your circumstance.
      </para>

    </sect3>
  </sect2>
<!-- There is a whole page about bridging for systemd in the "Connecting to
     a network" chapter
  <sect2 role="configuration" revision="systemd">
    <title>Configuring bridge-utils</title>

    <sect3 id='bridgeutils-init-systemd'>
      <title>Configuration Information</title>
      <para>
        TBA
      </para>
    </sect3>
  </sect2>
-->


  <sect2 role="content">
    <title>Contents</title>

    <segmentedlist>
      <segtitle>Installed Program</segtitle>
      <segtitle>Installed Libraries</segtitle>
      <segtitle>Installed Directories</segtitle>

      <seglistitem>
        <seg>brctl</seg>
        <seg>None</seg>
        <seg>None</seg>
      </seglistitem>
    </segmentedlist>

    <variablelist>
      <bridgehead renderas="sect3">Short Descriptions</bridgehead>
      <?dbfo list-presentation="list"?>
      <?dbhtml list-presentation="table"?>

      <varlistentry id="brctl">
        <term><command>brctl</command></term>
        <listitem>
          <para>
            is a program  used to set up, maintain, and inspect the
            ethernet bridge configuration in the linux kernel
          </para>
          <indexterm zone="bridgeutils brctl">
            <primary sortas="b-brctl">brctl</primary>
          </indexterm>
        </listitem>
      </varlistentry>

    </variablelist>

  </sect2>

</sect1>