ovn: Avoid ARP responder for packets from localnet port

[cascardo/ovs.git] / ovn / northd / ovn-northd.8.xml

diff --git a/ovn/northd/ovn-northd.8.xml b/ovn/northd/ovn-northd.8.xml
index e7dec72..cacd760 100644 (file)
--- a/ovn/northd/ovn-northd.8.xml
+++ b/ovn/northd/ovn-northd.8.xml
@@ -195,7 +195,52 @@
       </li>
     </ul>
 
-    <h3>Ingress Table 3: Destination Lookup</h3>
+    <h3>Ingress Table 3: ARP responder</h3>
+
+    <p>
+      This table implements ARP responder for known IPs.  It contains these
+      logical flows:
+    </p>
+
+    <ul>
+      <li>
+        Priority-100 flows to skip ARP responder if inport is of type
+        <code>localnet</code>, and advances directly to table 3.
+      </li>
+
+      <li>
+        <p>
+          Priority-50 flows that matches ARP requests to each known IP address
+          <var>A</var> of logical port <var>P</var>, and respond with ARP
+          replies directly with corresponding Ethernet address <var>E</var>:
+        </p>
+
+        <pre>
+eth.dst = eth.src;
+eth.src = <var>E</var>;
+arp.op = 2; /* ARP reply. */
+arp.tha = arp.sha;
+arp.sha = <var>E</var>;
+arp.tpa = arp.spa;
+arp.spa = <var>A</var>;
+outport = <var>P</var>;
+inport = ""; /* Allow sending out inport. */
+output;
+        </pre>
+
+        <p>
+          These flows are omitted for logical ports (other than router ports)
+          that are down.
+        </p>
+      </li>
+
+      <li>
+        One priority-0 fallback flow that matches all packets and advances to
+        table 4.
+      </li>
+    </ul>
+
+    <h3>Ingress Table 4: Destination Lookup</h3>
 
     <p>
       This table implements switching behavior.  It contains these logical
@@ -340,7 +385,7 @@ ip4.dst = ip4.src;
 ip4.src = <var>S</var>;
 ip.ttl = 255;
 icmp4.type = 0;
-inport = \"\"; /* Allow sending out inport. */
+inport = ""; /* Allow sending out inport. */
 next;
         </pre>
 
@@ -370,7 +415,7 @@ arp.sha = <var>E</var>;
 arp.tpa = arp.spa;
 arp.spa = <var>A</var>;
 outport = <var>P</var>;
-inport = \"\"; /* Allow sending out inport. */
+inport = ""; /* Allow sending out inport. */
 output;
         </pre>
       </li>