From 939e4b0616254c555a4bea5ba47e75ed72fe1c4c Mon Sep 17 00:00:00 2001
From: Martin Lopes <mlopes@redhat.com>
Date: Sun, 9 Mar 2014 00:26:23 +1000
Subject: [PATCH] Adds paragraph to ML2 overview

Adds a paragraph describing the circumstances that made ML2 a necessary
feature.

Change-Id: I9b698033ae9dc5acb603d02369914e8f3ca97294
Partial-Bug: #1230276
---
 doc/admin-guide-cloud/section_networking-scenarios.xml | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/doc/admin-guide-cloud/section_networking-scenarios.xml b/doc/admin-guide-cloud/section_networking-scenarios.xml
index 3d92b336ca..e9562fd343 100644
--- a/doc/admin-guide-cloud/section_networking-scenarios.xml
+++ b/doc/admin-guide-cloud/section_networking-scenarios.xml
@@ -599,6 +599,12 @@ physical_interface_mappings = physnet2:eth1</programlisting></para>
             simultaneously. This section describes different
             <emphasis>ML2</emphasis> plug-in and agent configurations with
             different type drivers and mechanism drivers.</para>
+        <para>Previously, Networking deployments were only able to use the
+            plug-in that had been selected at implementation time. For example,
+            a deployment running the Open vSwitch plug-in was only able to use
+            Open vSwitch exclusively; it wasn't possible to simultaneously run
+            another plug-in such as Linux Bridge. This was found to be a
+            limitation in environments with heterogeneous requirements.</para>
         <section xml:id="ml2_l2pop_scenarios">
             <title>ML2 with L2 population mechanism driver</title>
             <para>Current <emphasis>Open vSwitch</emphasis> and