Add support for ovn-ofctrl-wait-before-clear

Support was added for this option [1] to avoid dataplane downtime
during ovn upgrades where schema changes have happened. This
adds the ability for us to configure it.

[1] https://patchwork.ozlabs.org/project/ovn/patch/20220808182845.2746916-2-mmichels@redhat.com/

Change-Id: Ia3112b9a219b90af718c49776da49078449f09a2
(cherry picked from commit b5d38dcbd4)

manifests/controller.pp

@@ -100,6 +100,11 @@
 #  (optional) Create ovs bridges according to ovn_bridge_mappings.
 #  Defaults to true
 #
+# [*ovn_ofctrl_wait_before_clear*]
+#  (optional) Time (ms) to wait at startup before clearing openflow rules and
+#  install new ones.
+#  Defaults to 8000
+#
 class ovn::controller(
   $ovn_remote,
   $ovn_encap_ip,
@@ -119,7 +124,8 @@ class ovn::controller(
   $enable_ovn_match_northd     = false,
   $ovn_chassis_mac_map         = [],
   $ovn_monitor_all             = false,
-  $manage_ovs_bridge           = true
+  $manage_ovs_bridge           = true,
+  $ovn_ofctrl_wait_before_clear = 8000
 ) {
 
   include ovn::params
@@ -163,6 +169,7 @@ class ovn::controller(
     'external_ids:ovn-remote-probe-interval'    => { 'value' => $ovn_remote_probe_interval },
     'external_ids:ovn-openflow-probe-interval'  => { 'value' => $ovn_openflow_probe_interval },
     'external_ids:ovn-monitor-all'              => { 'value' => $ovn_monitor_all },
+    'external_ids:ovn-ofctrl-wait-before-clear' => { 'value' => $ovn_ofctrl_wait_before_clear },
   }
 
   if $ovn_cms_options {

releasenotes/notes/ovn_ofctrl_wait_before_clear-c40493ce231ec38c.yaml

@@ -0,0 +1,11 @@
+---
+features:
+  - |
+    The new ``ovn::controller::ovn_ofctrl_wait_before_clear`` parameter
+    has been added to resolve an issue with dataplane downtime during
+    upgrades that involve OVN schema changes. It will delay delting and
+    re-adding openflow rules by the configured time in ms to give
+    ovn-controller time to handle db connection / reconnection that can
+    happen in this case. The default of 8000ms is based on upstream OVN
+    testing with 200k openflow rules. Since it involved a change in
+    behavior, the upstream OVN value defaults to unset.

spec/classes/ovn_controller_spec.rb

@@ -77,6 +77,9 @@ describe 'ovn::controller' do
         is_expected.to contain_vs_config('external_ids:ovn-chassis-mac-mappings').with(
           :ensure => 'absent'
         )
+        is_expected.to contain_vs_config('external_ids:ovn-ofctrl-wait-before-clear').with(
+          :value => 8000
+        )
       end
 
       it 'configures bridge mappings' do
@@ -102,7 +105,8 @@ describe 'ovn::controller' do
           :ovn_transport_zones         => ['tz1'],
           :enable_ovn_match_northd     => false,
           :ovn_chassis_mac_map         => ['physnet1:aa:bb:cc:dd:ee:ff',
-                                           'physnet2:bb:aa:cc:dd:ee:ff']
+                                           'physnet2:bb:aa:cc:dd:ee:ff'],
+          :ovn_ofctrl_wait_before_clear => 9000
         })
       end
 
@@ -146,6 +150,9 @@ describe 'ovn::controller' do
         is_expected.to contain_vs_config('external_ids:ovn-chassis-mac-mappings').with(
           :value => 'physnet1:aa:bb:cc:dd:ee:ff,physnet2:bb:aa:cc:dd:ee:ff',
         )
+        is_expected.to contain_vs_config('external_ids:ovn-ofctrl-wait-before-clear').with(
+          :value => params[:ovn_ofctrl_wait_before_clear],
+        )
       end
 
       it 'configures bridge mappings' do