ovn: Change h1 titles to title case in documentation.

[cascardo/ovs.git] / ovn / ovn-architecture.7.xml

diff --git a/ovn/ovn-architecture.7.xml b/ovn/ovn-architecture.7.xml
index 31488bd..47dfc2a 100644 (file)
--- a/ovn/ovn-architecture.7.xml
+++ b/ovn/ovn-architecture.7.xml
@@ -678,6 +678,13 @@
         to enter the logical ingress pipeline.
       </p>
 
+      <p>
+        It's possible that a single ingress physical port maps to multiple
+        logical ports with a type of <code>localnet</code>. The logical datapath
+        and logical input port fields will be reset and the packet will be
+        resubmitted to table 16 multiple times.
+      </p>
+
       <p>
         Packets that originate from a container nested within a VM are treated
         in a slightly different way.  The originating container can be
@@ -810,6 +817,101 @@
     </li>
   </ol>
 
+  <h2>Life Cycle of a VTEP gateway</h2>
+
+  <p>
+    A gateway is a chassis that forwards traffic between the OVN-managed
+    part of a logical network and a physical VLAN,  extending a
+    tunnel-based logical network into a physical network.
+  </p>
+
+  <p>
+    The steps below refer often to details of the OVN and VTEP database
+    schemas.  Please see <code>ovn-sb</code>(5), <code>ovn-nb</code>(5)
+    and <code>vtep</code>(5), respectively, for the full story on these
+    databases.
+  </p>
+
+  <ol>
+    <li>
+      A VTEP gateway's life cycle begins with the administrator registering
+      the VTEP gateway as a <code>Physical_Switch</code> table entry in the
+      <code>VTEP</code> database.  The <code>ovn-controller-vtep</code>
+      connected to this VTEP database, will recognize the new VTEP gateway
+      and create a new <code>Chassis</code> table entry for it in the
+      <code>OVN_Southbound</code> database.
+    </li>
+
+    <li>
+      The administrator can then create a new <code>Logical_Switch</code>
+      table entry, and bind a particular vlan on a VTEP gateway's port to
+      any VTEP logical switch.  Once a VTEP logical switch is bound to
+      a VTEP gateway, the <code>ovn-controller-vtep</code> will detect
+      it and add its name to the <var>vtep_logical_switches</var>
+      column of the <code>Chassis</code> table in the <code>
+      OVN_Southbound</code> database.  Note, the <var>tunnel_key</var>
+      column of VTEP logical switch is not filled at creation.  The
+      <code>ovn-controller-vtep</code> will set the column when the
+      correponding vtep logical switch is bound to an OVN logical network.
+    </li>
+
+    <li>
+      Now, the administrator can use the CMS to add a VTEP logical switch
+      to the OVN logical network.  To do that, the CMS must first create a
+      new <code>Logical_Port</code> table entry in the <code>
+      OVN_Northbound</code> database.  Then, the <var>type</var> column
+      of this entry must be set to "vtep".  Next, the <var>
+      vtep-logical-switch</var> and <var>vtep-physical-switch</var> keys
+      in the <var>options</var> column must also be specified, since
+      multiple VTEP gateways can attach to the same VTEP logical switch.
+    </li>
+
+    <li>
+      The newly created logical port in the <code>OVN_Northbound</code>
+      database and its configuration will be passed down to the <code>
+      OVN_Southbound</code> database as a new <code>Port_Binding</code>
+      table entry.  The <code>ovn-controller-vtep</code> will recognize the
+      change and bind the logical port to the corresponding VTEP gateway
+      chassis.  Configuration of binding the same VTEP logical switch to
+      a different OVN logical networks is not allowed and a warning will be
+      generated in the log.
+    </li>
+
+    <li>
+      Beside binding to the VTEP gateway chassis, the <code>
+      ovn-controller-vtep</code> will update the <var>tunnel_key</var>
+      column of the VTEP logical switch to the corresponding <code>
+      Datapath_Binding</code> table entry's <var>tunnel_key</var> for the
+      bound OVN logical network.
+    </li>
+
+    <li>
+      Next, the <code>ovn-controller-vtep</code> will keep reacting to the
+      configuration change in the <code>Port_Binding</code> in the
+      <code>OVN_Northbound</code> database, and updating the
+      <code>Ucast_Macs_Remote</code> table in the <code>VTEP</code> database.
+      This allows the VTEP gateway to understand where to forward the unicast
+      traffic coming from the extended external network.
+    </li>
+
+    <li>
+      Eventually, the VTEP gateway's life cycle ends when the administrator
+      unregisters the VTEP gateway from the <code>VTEP</code> database.
+      The <code>ovn-controller-vtep</code> will recognize the event and
+      remove all related configurations (<code>Chassis</code> table entry
+      and port bindings) in the <code>OVN_Southbound</code> database.
+    </li>
+
+    <li>
+      When the <code>ovn-controller-vtep</code> is terminated, all related
+      configurations in the <code>OVN_Southbound</code> database and
+      the <code>VTEP</code> database will be cleaned, including
+      <code>Chassis</code> table entries for all registered VTEP gateways
+      and their port bindings, and all <code>Ucast_Macs_Remote</code> table
+      entries and the <code>Logical_Switch</code> tunnel keys.
+    </li>
+  </ol>
+
   <h1>Design Decisions</h1>
 
   <h2>Tunnel Encapsulations</h2>