Mention optional networks

I updated the text to mention optional network interfaces
and networks present in the improved diagrams. I also
mentioned the progression toward use of automation tools
for production environments.

Change-Id: I4546662b9d9602343f69b1f7d1a6f2092b0e403e
Implements: blueprint installation-guide-improvements
backport: juno

doc/install-guide/ch_overview.xml

@@ -26,6 +26,8 @@
       xpointer="element(table1)"/>
     <para>This guide describes how to deploy these services in a functional
       test environment and, by example, teaches you how to build a production
+      environment. Realistically, you would use automation tools such as
+      Ansible, Chef, and Puppet to deploy and manage a production
       environment.</para>
   </section>
   <section xml:id="architecture_conceptual-architecture">
@@ -65,7 +67,7 @@
               supporting services such as a SQL database,
               <glossterm>message queue</glossterm>, and
               <glossterm>Network Time Protocol (NTP)</glossterm>.</para>
-            <para>Optionally, the controller node also runs portions of
+            <para>Optionally, the controller node runs portions of
               Block Storage, Object Storage, Orchestration, Telemetry,
               Database, and Data Processing services. These
               components provide additional features for your
@@ -93,22 +95,29 @@
               (<glossterm baseform="security group"
               >security groups</glossterm>) services. You can run more
               than one compute node.</para>
-            <para>Optionally, the compute node also runs a Telemetry
-              agent to collect metrics.</para>
+            <para>Optionally, the compute node runs a Telemetry
+              agent to collect metrics. Also, it can contain a third
+              network interface on a separate storage network to improve
+              performance of storage services.</para>
           </listitem>
           <listitem>
             <para>The optional Block Storage node contains the disks that
               the Block Storage service provisions for tenant virtual machine
               instances. You can run more than one of these nodes.</para>
-            <para>Optionally, the Block Storage node also runs a Telemetry
-              agent to collect metrics.</para>
+            <para>Optionally, the Block Storage node runs a Telemetry
+              agent to collect metrics. Also, it can contain a second
+              network interface on a separate storage network to improve
+              performance of storage services.</para>
           </listitem>
           <listitem>
             <para>The optional Object Storage nodes contain the disks that
               the Object Storage service uses for storing accounts,
               containers, and objects. You can run more than two of these
               nodes. However, the minimal architecture example requires
               two nodes.</para>
+            <para>Optionally, these nodes can contain a second network
+              interface on a separate storage network to improve
+              performance of storage services.</para>
           </listitem>
         </itemizedlist>
         <note>
@@ -163,7 +172,7 @@
               dashboard. It also includes supporting services such as
               a SQL database, <glossterm>message queue</glossterm>, and
               <glossterm>Network Time Protocol (NTP)</glossterm>.</para>
-            <para>Optionally, the controller node also runs portions of
+            <para>Optionally, the controller node runs portions of
               Block Storage, Object Storage, Orchestration, Telemetry,
               Database, and Data Processing services. These
               components provide additional features for your
@@ -181,22 +190,29 @@
               (<glossterm baseform="security group"
               >security groups</glossterm>) services. You can run more
               than one compute node.</para>
-            <para>Optionally, the compute node also runs a Telemetry
-              agent to collect metrics.</para>
+            <para>Optionally, the compute node runs a Telemetry
+              agent to collect metrics. Also, it can contain a third
+              network interface on a separate storage network to improve
+              performance of storage services.</para>
           </listitem>
           <listitem>
             <para>The optional Block Storage node contains the disks that
               the Block Storage service provisions for tenant virtual machine
               instances. You can run more than one of these nodes.</para>
-            <para>Optionally, the Block Storage node also runs a Telemetry
-              agent to collect metrics.</para>
+            <para>Optionally, the Block Storage node runs a Telemetry
+              agent to collect metrics. Also, it can contain a second
+              network interface on a separate storage network to improve
+              performance of storage services.</para>
           </listitem>
           <listitem>
             <para>The optional Object Storage nodes contain the disks that
               the Object Storage service uses for storing accounts,
               containers, and objects. You can run more than two of these
               nodes. However, the minimal architecture example requires
               two nodes.</para>
+            <para>Optionally, these nodes can contain a second network
+              interface on a separate storage network to improve
+              performance of storage services.</para>
           </listitem>
         </itemizedlist>
         <note>