Enable Windows bridge local interface forwarding

Since now all traffic from uplink interface is output to bridge
local interface directly instead of being resubmitted to
UplinkTable, for connection of Service LoadBalancer, when the
client is from external network and Endpoint is a backend Pod,
if bridge local interface forwarding is not enabled, such
connection whose source is from external network and
destination is not local Node will be discarded on bridge local
interface.

Signed-off-by: Hongliang Liu <lhongliang@vmware.com>

pkg/agent/agent_windows.go

@@ -188,6 +188,13 @@ func (i *Initializer) prepareOVSBridge() error {
 		err = nil
 		klog.V(4).Infof("Address: %s already exists when configuring IP on interface %s", uplinkNetConfig.IP.String(), brName)
 	}
+	// Enable bridge local interface forwarding. Since now all traffic from uplink interface is output to bridge local interface
+	// directly instead of being resubmitted to UplinkTable, for connection of Service LoadBalancer, when the client is from
+	// external network and Endpoint is a backend Pod, if bridge local interface forwarding is not enabled, such connection
+	// whose source is from external network and destination is not local Node will be discarded on bridge local interface.
+	if err = util.EnableIPForwarding(brName); err != nil {
+		return err
+	}
 	// Restore the host routes which are lost when moving the network configuration of the uplink interface to OVS bridge interface.
 	if err = i.restoreHostRoutes(); err != nil {
 		return err