fix: cancel delete staticroute when it's used by NatRule (#1733)

Signed-off-by: xujunjie-cover <xujunjielxx@163.com>

(cherry picked from commit f582a11)

pkg/controller/gc.go

@@ -544,6 +544,10 @@ func (c *Controller) gcStaticRoute() error {
 	for _, route := range routes {
 		if route.Policy == ovs.PolicyDstIP || route.Policy == "" {
 			if !c.ipam.ContainAddress(route.NextHop) {
+				exist, err := c.ovnClient.NatRuleExists(route.CIDR)
+				if exist || err != nil {
+					continue
+				}
 				klog.Infof("gc static route %s %s %s", route.Policy, route.CIDR, route.NextHop)
 				if err := c.ovnClient.DeleteStaticRouteByNextHop(route.NextHop); err != nil {
 					klog.Errorf("failed to delete stale nexthop route %s, %v", route.NextHop, err)

pkg/ovs/ovn-nbctl.go

@@ -828,6 +828,18 @@ func (c Client) DeleteNatRule(logicalIP, router string) error {
 	return err
 }
 
+func (c *Client) NatRuleExists(logicalIP string) (bool, error) {
+	results, err := c.CustomFindEntity("NAT", []string{"external_ip"}, fmt.Sprintf("logical_ip=%s", logicalIP))
+	if err != nil {
+		klog.Errorf("customFindEntity failed, %v", err)
+		return false, err
+	}
+	if len(results) == 0 {
+		return false, nil
+	}
+	return true, nil
+}
+
 func (c Client) DeleteMatchedStaticRoute(cidr, nexthop, router string) error {
 	if cidr == "" || nexthop == "" {
 		return nil