reserve pod eip static route when update vpc (#2185)

pkg/controller/vpc.go

@@ -395,6 +395,40 @@ func (c *Controller) handleAddOrUpdateVpc(key string) error {
 				NextHopIP: gatewayV6,
 			})
 		}
+
+		if c.config.EnableEipSnat {
+			cm, err := c.configMapsLister.ConfigMaps(c.config.ExternalGatewayConfigNS).Get(util.ExternalGatewayConfig)
+			if err == nil {
+				nextHop := cm.Data["external-gw-addr"]
+				if nextHop == "" {
+					klog.Errorf("no available gateway nic address")
+					return fmt.Errorf("no available gateway nic address")
+				}
+				if strings.Contains(nextHop, "/") {
+					nextHop = strings.Split(nextHop, "/")[0]
+				}
+
+				nats, err := c.ovnLegacyClient.GetRouterNat(vpc.Name)
+				if err != nil {
+					klog.Errorf("failed to get nat for vpc %s, %v", vpc.Name, err)
+					return err
+				}
+				for _, nat := range nats {
+					logical_ip, err := c.ovnLegacyClient.GetNatIPInfo(nat)
+					if err != nil {
+						klog.Errorf("failed to get nat ip info for vpc %s, %v", vpc.Name, err)
+						return err
+					}
+					if logical_ip != "" {
+						targetRoutes = append(targetRoutes, &kubeovnv1.StaticRoute{
+							Policy:    kubeovnv1.PolicySrc,
+							CIDR:      logical_ip,
+							NextHopIP: nextHop,
+						})
+					}
+				}
+			}
+		}
 	}
 
 	routeNeedDel, routeNeedAdd, err := diffStaticRoute(existRoute, targetRoutes)

pkg/ovs/ovn-nbctl-legacy.go

@@ -2737,3 +2737,33 @@ func (c LegacyClient) SetAclLog(pgName string, logEnable, isIngress bool) error
 
 	return nil
 }
+
+func (c *LegacyClient) GetRouterNat(routerName string) ([]string, error) {
+	var nat []string
+	results, err := c.CustomFindEntity("logical-router", []string{"nat"}, fmt.Sprintf("name=%s", routerName))
+	if err != nil {
+		klog.Errorf("customFindEntity failed, %v", err)
+		return nat, err
+	}
+	if len(results) == 0 {
+		return nat, nil
+	}
+
+	return results[0]["nat"], nil
+}
+
+func (c *LegacyClient) GetNatIPInfo(uuid string) (string, error) {
+	var logical_ip string
+
+	output, err := c.ovnNbCommand("--data=bare", "--format=csv", "--no-heading", "--columns=logical_ip", "list", "nat", uuid)
+	if err != nil {
+		klog.Errorf("failed to list nat, %v", err)
+		return logical_ip, err
+	}
+	lines := strings.Split(output, "\n")
+
+	if len(lines) > 0 {
+		logical_ip = strings.TrimSpace(lines[0])
+	}
+	return logical_ip, nil
+}