Fixes OVN upgrade with shared gateway mode

With OCP upgrade today, CNO happens before MCO. When upgrading from 4.5
to 4.6, 4.6 OVN expects system OVS to be there and configured which will
not happen until MCO upgrade finishes. Therefore upon initial CNO
upgrade, we will run in local gateway mode until the node is rebooted
via MCO with a machine-os-content change to include system OVS and run
the ovs-configuration service.

Signed-off-by: Tim Rozet <trozet@redhat.com>

bindata/network/ovn-kubernetes/ovnkube-master.yaml

@@ -495,6 +495,15 @@ spec:
             fi
           fi
 
+          gateway_mode_flags=
+          # Check to see if ovs is provided by the node. This is only for upgrade from 4.5->4.6
+          # REMOVEME in 4.7
+          if systemctl status ovsdb-server; then
+            gateway_mode_flags="--gateway-mode shared --gateway-interface br-ex"
+          else
+            gateway_mode_flags="--gateway-mode local"
+          fi
+
           # start nbctl daemon for caching
           echo "I$(date "+%m%d %H:%M:%S.%N") - ovnkube-master - start nbctl daemon for caching"
           export OVN_NB_DAEMON=$(ovn-nbctl --pidfile=/var/run/ovn/ovn-nbctl.pid \
@@ -513,8 +522,7 @@ spec:
             --loglevel "${OVN_KUBE_LOG_LEVEL}" \
             ${hybrid_overlay_flags} \
             --metrics-bind-address "127.0.0.1:29102" \
-            --gateway-mode shared \
-            --gateway-interface br-ex \
+            ${gateway_mode_flags} \
             --sb-address "{{.OVN_SB_DB_LIST}}" \
             --sb-client-privkey /ovn-cert/tls.key \
             --sb-client-cert /ovn-cert/tls.crt \

bindata/network/ovn-kubernetes/ovnkube-node.yaml

@@ -129,7 +129,16 @@ spec:
               hybrid_overlay_flags="${hybrid_overlay_flags} --hybrid-overlay-vxlan-port={{.OVNHybridOverlayVXLANPort}}"
             fi
           fi
-          
+
+          gateway_mode_flags=
+          # Check to see if ovs is provided by the node. This is only for upgrade from 4.5->4.6
+          # REMOVEME in 4.7
+          if systemctl status ovsdb-server; then
+            gateway_mode_flags="--gateway-mode shared --gateway-interface br-ex"
+          else
+            gateway_mode_flags="--gateway-mode local"
+          fi
+
           exec /usr/bin/ovnkube --init-node "${K8S_NODE}" \
             --nb-address "{{.OVN_NB_DB_LIST}}" \
             --sb-address "{{.OVN_SB_DB_LIST}}" \
@@ -145,8 +154,7 @@ spec:
             --loglevel "${OVN_KUBE_LOG_LEVEL}" \
             --inactivity-probe="${OVN_CONTROLLER_INACTIVITY_PROBE}" \
             ${hybrid_overlay_flags} \
-            --gateway-mode shared \
-            --gateway-interface br-ex \
+            ${gateway_mode_flags} \
             --metrics-bind-address "127.0.0.1:29103"
         env:
         # for kubectl