@@ -2692,7 +2692,10 @@ outport = <var>P</var>;
<code>Logical_Switch_Port</code> table. For router ports
connected to other logical routers, MAC bindings can be known
statically from the <code>mac</code> and <code>networks</code>
- column in the <code>Logical_Router_Port</code> table.
+ column in the <code>Logical_Router_Port</code> table. (Note: the
+ flow is NOT installed for the IP addresses that belong to a neighbor
+ logical router port if the current router has the
+ <code>options:dynamic_neigh_routers</code> set to <code>true</code>)
</p>
<p>
@@ -9997,6 +9997,12 @@ build_lrouter_flows(struct hmap *datapaths, struct hmap *ports,
continue;
}
+ if (peer->od->nbr &&
+ smap_get_bool(&peer->od->nbr->options,
+ "dynamic_neigh_routers", false)) {
+ continue;
+ }
+
for (size_t i = 0; i < op->od->n_router_ports; i++) {
const char *router_port_name = smap_get(
&op->od->router_ports[i]->nbsp->options,
@@ -1840,6 +1840,19 @@
connected to the logical router. Default: False.
</p>
</column>
+ <column name="options" key="dynamic_neigh_routers" type='{"type": "boolean"}'>
+ <p>
+ If set to <code>true</code>, the router will resolve neighbor
+ routers' MAC addresses only by dynamic ARP/ND, instead of
+ prepopulating static mappings for all neighbor routers in the ARP/ND
+ Resolution stage. This reduces number of flows, but requires ARP/ND
+ messages to resolve the IP-MAC bindings when needed. It is
+ <code>false</code> by default. It is recommended to set to
+ <code>true</code> when a large number of logical routers are
+ connected to the same logical switch but most of them never need to
+ send traffic between each other.
+ </p>
+ </column>
</group>
<group title="Common Columns">
Support option:dynamic_neigh_routers for logical routers, so that in particular use cases static neighbor flows are not prepopulated IP addresses belonging to neighbor router ports, to avoid flow exploding problem reported for ovn-kubernetes large scale setup. Reported-by: Girish Moodalbail <gmoodalbail@gmail.com> Reported-at: https://mail.openvswitch.org/pipermail/ovs-discuss/2020-May/049995.html Signed-off-by: Han Zhou <hzhou@ovn.org> --- v1 -> v2: Change the options to skip flows only for routers. In v1 it skipped other neighbor flows but not router neighbors which was not the purpose of this patch. northd/ovn-northd.8.xml | 5 ++++- northd/ovn-northd.c | 6 ++++++ ovn-nb.xml | 13 +++++++++++++ 3 files changed, 23 insertions(+), 1 deletion(-)