admin-guide-cloud: Document Neutron Metering Agent

Neutron Metering Agent has been introduced in Havana release.
This patch adds the agent in Neutron Diagram and explains the process to
install the agent on the network nodes.

Change-Id: Id8f16aab44af18141a63fa873d9f856f83f444a4
backport: havana
Signed-off-by: Emilien Macchi <emilien.macchi@enovance.com>

doc/admin-guide-cloud/section_networking_arch.xml

@@ -65,7 +65,7 @@
                                 this agent.</td>
                         </tr>
                         <tr>
-                            <td><emphasis role="bold">l3 metering agent</emphasis>
+                            <td><emphasis role="bold">metering agent</emphasis>
                                     (<literal>neutron-metering-agent</literal>)</td>
                             <td>Provides L3 traffic measurements for tenant networks.</td>
                         </tr>

doc/admin-guide-cloud/section_networking_introduction.xml

@@ -841,8 +841,9 @@ password = "PLUMgrid-director-admin-password"</programlisting>
                 class="service">nova-compute</systemitem> and nodes
             that run dedicated OpenStack Networking service agents
             such as <systemitem>neutron-dhcp-agent</systemitem>,
-                <systemitem>neutron-l3-agent</systemitem>, or
-                <systemitem>neutron-lbaas-agent</systemitem>.</para>
+            <systemitem>neutron-l3-agent</systemitem>,
+            <systemitem>neutron-metering-agent</systemitem> or
+            <systemitem>neutron-lbaas-agent</systemitem>.</para>
         <para>A data-forwarding node typically has a network interface
             with an IP address on the “management network” and another
             interface on the “data network”.</para>
@@ -1213,6 +1214,45 @@ interface_driver = neutron.agent.linux.interface.OVSInterfaceDriver</programlist
                     starts.</para>
             </important>
         </section>
+        <section xml:id="install_neutron-metering-agent">
+            <title>Configure metering agent</title>
+            <para>Starting with the Havana release, the Neutron Metering resides beside
+                    <systemitem>neutron-l3-agent</systemitem>.</para>
+            <procedure>
+                <title>To install the metering agent and configure the
+                    node</title>
+                <step>
+                    <para>Install the agent by running:</para>
+                    <screen><prompt>#</prompt> <userinput>sudo apt-get install neutron-metering-agent</userinput></screen>
+                </step>
+                <step>
+                    <para>If you use one of the following plugins, you need to configure the metering agent with these lines as well:</para>
+                    <itemizedlist>
+                        <listitem>
+                            <para>An OVS-based plug-in such as OVS,
+                                NSX, Ryu, NEC,
+                                BigSwitch/Floodlight:</para>
+                            <programlisting language="ini">interface_driver = neutron.agent.linux.interface.OVSInterfaceDriver</programlisting>
+                        </listitem>
+                        <listitem>
+                            <para>A plug-in that uses LinuxBridge:</para>
+                            <programlisting language="ini">interface_driver = neutron.agent.linux.interface.BridgeInterfaceDriver</programlisting>
+                        </listitem>
+                    </itemizedlist>
+                </step>
+                <step>
+                    <para>To use the reference implementation, you
+                        must set:</para>
+                    <programlisting language="ini">driver = neutron.services.metering.drivers.iptables.iptables_driver.IptablesMeteringDriver</programlisting>
+                </step>
+                <step>
+                    <para>Set this parameter in the
+                            <filename>neutron.conf</filename> file on
+                        the host that runs <systemitem class="service">neutron-server</systemitem>:</para>
+                    <programlisting language="ini">service_plugins = neutron.services.metering.metering_plugin.MeteringPlugin</programlisting>
+                </step>
+            </procedure>
+        </section>
         <section xml:id="install_neutron-lbaas-agent">
             <title>Configure LBaaS agent</title>
             <para>Starting with the Havana release, the Neutron