Merge pull request #94991 from nilo19/feature/support-shared-pip

Azure: Support multiple services sharing one IP address

staging/src/k8s.io/legacy-cloud-providers/azure/azure_backoff.go

@@ -42,6 +42,8 @@ const (
 
 	// operationCanceledErrorMessage means the operation is canceled by another new operation.
 	operationCanceledErrorMessage = "canceledandsupersededduetoanotheroperation"
+
+	cannotDeletePublicIPErrorMessageCode = "PublicIPAddressCannotBeDeleted"
 )
 
 // RequestBackoff if backoff is disabled in cloud provider it
@@ -275,6 +277,11 @@ func (az *Cloud) DeletePublicIP(service *v1.Service, pipResourceGroup string, pi
 	if rerr != nil {
 		klog.Errorf("PublicIPAddressesClient.Delete(%s) failed: %s", pipName, rerr.Error().Error())
 		az.Event(service, v1.EventTypeWarning, "DeletePublicIPAddress", rerr.Error().Error())
+
+		if strings.Contains(rerr.Error().Error(), cannotDeletePublicIPErrorMessageCode) {
+			klog.Warningf("DeletePublicIP for public IP %s failed with error %v, this is because other resources are referencing the public IP. The deletion of the service will continue.", pipName, rerr.Error())
+			return nil
+		}
 		return rerr.Error()
 	}
 

staging/src/k8s.io/legacy-cloud-providers/azure/azure_loadbalancer.go

@@ -108,6 +108,8 @@ const (
 	serviceTagKey = "service"
 	// clusterNameKey is the cluster name key applied for public IP tags.
 	clusterNameKey = "kubernetes-cluster-name"
+	// serviceUsingDNSKey is the service name consuming the DNS label on the public IP
+	serviceUsingDNSKey = "kubernetes-dns-label-service"
 
 	defaultLoadBalancerSourceRanges = "0.0.0.0/0"
 )
@@ -414,10 +416,15 @@ func (az *Cloud) getServiceLoadBalancerStatus(service *v1.Service, lb *network.L
 		return nil, nil
 	}
 	isInternal := requiresInternalLoadBalancer(service)
-	lbFrontendIPConfigName := az.getFrontendIPConfigName(service)
 	serviceName := getServiceName(service)
 	for _, ipConfiguration := range *lb.FrontendIPConfigurations {
-		if lbFrontendIPConfigName == *ipConfiguration.Name {
+		owns, isPrimaryService, err := az.serviceOwnsFrontendIP(ipConfiguration, service)
+		if err != nil {
+			return nil, fmt.Errorf("get(%s): lb(%s) - failed to filter frontend IP configs with error: %v", serviceName, to.String(lb.Name), err)
+		}
+		if owns {
+			klog.V(2).Infof("get(%s): lb(%s) - found frontend IP config, primary service: %v", serviceName, to.String(lb.Name), isPrimaryService)
+
 			var lbIP *string
 			if isInternal {
 				lbIP = ipConfiguration.PrivateIPAddress
@@ -442,7 +449,7 @@ func (az *Cloud) getServiceLoadBalancerStatus(service *v1.Service, lb *network.L
 				}
 			}
 
-			klog.V(2).Infof("getServiceLoadBalancerStatus gets ingress IP %q from frontendIPConfiguration %q for service %q", to.String(lbIP), lbFrontendIPConfigName, serviceName)
+			klog.V(2).Infof("getServiceLoadBalancerStatus gets ingress IP %q from frontendIPConfiguration %q for service %q", to.String(lbIP), to.String(ipConfiguration.Name), serviceName)
 			return &v1.LoadBalancerStatus{Ingress: []v1.LoadBalancerIngress{{IP: to.String(lbIP)}}}, nil
 		}
 	}
@@ -457,25 +464,43 @@ func (az *Cloud) determinePublicIPName(clusterName string, service *v1.Service)
 		return name, shouldPIPExisted, nil
 	}
 
+	pipResourceGroup := az.getPublicIPAddressResourceGroup(service)
 	loadBalancerIP := service.Spec.LoadBalancerIP
+
+	// Assume that the service without loadBalancerIP set is a primary service.
+	// If a secondary service doesn't set the loadBalancerIP, it is not allowed to share the IP.
 	if len(loadBalancerIP) == 0 {
 		return az.getPublicIPName(clusterName, service), shouldPIPExisted, nil
 	}
 
-	pipResourceGroup := az.getPublicIPAddressResourceGroup(service)
+	// For the services with loadBalancerIP set, an existing public IP is required, primary
-
+	// or secondary, or a public IP not found error would be reported.
-	pips, err := az.ListPIP(service, pipResourceGroup)
+	pip, err := az.findMatchedPIPByLoadBalancerIP(service, loadBalancerIP, pipResourceGroup)
 	if err != nil {
 		return "", shouldPIPExisted, err
 	}
 
+	if pip != nil && pip.Name != nil {
+		return *pip.Name, shouldPIPExisted, nil
+	}
+
+	return "", shouldPIPExisted, fmt.Errorf("user supplied IP Address %s was not found in resource group %s", loadBalancerIP, pipResourceGroup)
+}
+
+func (az *Cloud) findMatchedPIPByLoadBalancerIP(service *v1.Service, loadBalancerIP, pipResourceGroup string) (*network.PublicIPAddress, error) {
+	pips, err := az.ListPIP(service, pipResourceGroup)
+	if err != nil {
+		return nil, err
+	}
+
 	for _, pip := range pips {
 		if pip.PublicIPAddressPropertiesFormat.IPAddress != nil &&
 			*pip.PublicIPAddressPropertiesFormat.IPAddress == loadBalancerIP {
-			return *pip.Name, shouldPIPExisted, nil
+			return &pip, nil
 		}
 	}
-	return "", shouldPIPExisted, fmt.Errorf("user supplied IP Address %s was not found in resource group %s", loadBalancerIP, pipResourceGroup)
+
+	return nil, fmt.Errorf("findMatchedPIPByLoadBalancerIP: cannot find public IP with IP address %s in resource group %s", loadBalancerIP, pipResourceGroup)
 }
 
 func flipServiceInternalAnnotation(service *v1.Service) *v1.Service {
@@ -532,10 +557,39 @@ func (az *Cloud) ensurePublicIPExists(service *v1.Service, pipName string, domai
 	serviceName := getServiceName(service)
 
 	if existsPip {
+		// ensure that the service tag is good
+		changed, err := bindServicesToPIP(&pip, []string{serviceName}, false)
+		if err != nil {
+			return nil, err
+		}
+
 		// return if pip exist and dns label is the same
-		if getDomainNameLabel(&pip) == domainNameLabel {
+		if strings.EqualFold(getDomainNameLabel(&pip), domainNameLabel) {
+			if existingServiceName, ok := pip.Tags[serviceUsingDNSKey]; ok &&
+				strings.EqualFold(*existingServiceName, serviceName) {
+				klog.V(6).Infof("ensurePublicIPExists for service(%s): pip(%s) - "+
+					"the service is using the DNS label on the public IP", serviceName, pipName)
+
+				var rerr *retry.Error
+				if changed {
+					klog.V(2).Infof("ensurePublicIPExists: updating the PIP %s for the incoming service %s", pipName, serviceName)
+					err = az.CreateOrUpdatePIP(service, pipResourceGroup, pip)
+					if err != nil {
+						return nil, err
+					}
+
+					ctx, cancel := getContextWithCancel()
+					defer cancel()
+					pip, rerr = az.PublicIPAddressesClient.Get(ctx, pipResourceGroup, *pip.Name, "")
+					if rerr != nil {
+						return nil, rerr.Error()
+					}
+				}
+
 				return &pip, nil
 			}
+		}
+
 		klog.V(2).Infof("ensurePublicIPExists for service(%s): pip(%s) - updating", serviceName, *pip.Name)
 		if pip.PublicIPAddressPropertiesFormat == nil {
 			pip.PublicIPAddressPropertiesFormat = &network.PublicIPAddressPropertiesFormat{
@@ -553,9 +607,13 @@ func (az *Cloud) ensurePublicIPExists(service *v1.Service, pipName string, domai
 			IPTags:                   getServiceIPTagRequestForPublicIP(service).IPTags,
 		}
 		pip.Tags = map[string]*string{
-			serviceTagKey:  &serviceName,
+			serviceTagKey:  to.StringPtr(""),
 			clusterNameKey: &clusterName,
 		}
+		if _, err = bindServicesToPIP(&pip, []string{serviceName}, false); err != nil {
+			return nil, err
+		}
+
 		if az.useStandardLoadBalancer() {
 			pip.Sku = &network.PublicIPAddressSku{
 				Name: network.PublicIPAddressSkuNameStandard,
@@ -564,12 +622,28 @@ func (az *Cloud) ensurePublicIPExists(service *v1.Service, pipName string, domai
 		klog.V(2).Infof("ensurePublicIPExists for service(%s): pip(%s) - creating", serviceName, *pip.Name)
 	}
 	if foundDNSLabelAnnotation {
+		if existingServiceName, ok := pip.Tags[serviceUsingDNSKey]; ok {
+			if !strings.EqualFold(to.String(existingServiceName), serviceName) {
+				return nil, fmt.Errorf("ensurePublicIPExists for service(%s): pip(%s) - there is an existing service %s consuming the DNS label on the public IP, so the service cannot set the DNS label annotation with this value", serviceName, pipName, *existingServiceName)
+			}
+		}
+
 		if len(domainNameLabel) == 0 {
 			pip.PublicIPAddressPropertiesFormat.DNSSettings = nil
 		} else {
+			if pip.PublicIPAddressPropertiesFormat.DNSSettings == nil ||
+				pip.PublicIPAddressPropertiesFormat.DNSSettings.DomainNameLabel == nil {
+				klog.V(6).Infof("ensurePublicIPExists for service(%s): pip(%s) - no existing DNS label on the public IP, create one", serviceName, pipName)
 				pip.PublicIPAddressPropertiesFormat.DNSSettings = &network.PublicIPAddressDNSSettings{
 					DomainNameLabel: &domainNameLabel,
 				}
+			} else {
+				existingDNSLabel := pip.PublicIPAddressPropertiesFormat.DNSSettings.DomainNameLabel
+				if !strings.EqualFold(to.String(existingDNSLabel), domainNameLabel) {
+					return nil, fmt.Errorf("ensurePublicIPExists for service(%s): pip(%s) - there is an existing DNS label %s on the public IP", serviceName, pipName, *existingDNSLabel)
+				}
+			}
+			pip.Tags[serviceUsingDNSKey] = &serviceName
 		}
 	}
 
@@ -729,7 +803,11 @@ func getIdleTimeout(s *v1.Service) (*int32, error) {
 }
 
 func (az *Cloud) isFrontendIPChanged(clusterName string, config network.FrontendIPConfiguration, service *v1.Service, lbFrontendIPConfigName string) (bool, error) {
-	if az.serviceOwnsFrontendIP(config, service) && !strings.EqualFold(to.String(config.Name), lbFrontendIPConfigName) {
+	isServiceOwnsFrontendIP, isPrimaryService, err := az.serviceOwnsFrontendIP(config, service)
+	if err != nil {
+		return false, err
+	}
+	if isServiceOwnsFrontendIP && isPrimaryService && !strings.EqualFold(to.String(config.Name), lbFrontendIPConfigName) {
 		return true, nil
 	}
 	if !strings.EqualFold(to.String(config.Name), lbFrontendIPConfigName) {
@@ -775,6 +853,134 @@ func (az *Cloud) isFrontendIPChanged(clusterName string, config network.Frontend
 	return config.PublicIPAddress != nil && !strings.EqualFold(to.String(pip.ID), to.String(config.PublicIPAddress.ID)), nil
 }
 
+// isFrontendIPConfigIsUnsafeToDelete checks if a frontend IP config is safe to be deleted.
+// It is safe to be deleted if and only if there is no reference from other
+// loadBalancing resources, including loadBalancing rules, outbound rules, inbound NAT rules
+// and inbound NAT pools.
+func (az *Cloud) isFrontendIPConfigIsUnsafeToDelete(
+	lb *network.LoadBalancer,
+	service *v1.Service,
+	fipConfigID *string,
+) (bool, error) {
+	if lb == nil || fipConfigID == nil || *fipConfigID == "" {
+		return false, fmt.Errorf("isFrontendIPConfigIsUnsafeToDelete: incorrect parameters")
+	}
+
+	var (
+		lbRules         []network.LoadBalancingRule
+		outboundRules   []network.OutboundRule
+		inboundNatRules []network.InboundNatRule
+		inboundNatPools []network.InboundNatPool
+		unsafe          bool
+	)
+
+	if lb.LoadBalancerPropertiesFormat != nil {
+		if lb.LoadBalancingRules != nil {
+			lbRules = *lb.LoadBalancingRules
+		}
+		if lb.OutboundRules != nil {
+			outboundRules = *lb.OutboundRules
+		}
+		if lb.InboundNatRules != nil {
+			inboundNatRules = *lb.InboundNatRules
+		}
+		if lb.InboundNatPools != nil {
+			inboundNatPools = *lb.InboundNatPools
+		}
+	}
+
+	// check if there are load balancing rules from other services
+	// referencing this frontend IP configuration
+	for _, lbRule := range lbRules {
+		if lbRule.LoadBalancingRulePropertiesFormat != nil &&
+			lbRule.FrontendIPConfiguration != nil &&
+			lbRule.FrontendIPConfiguration.ID != nil &&
+			strings.EqualFold(*lbRule.FrontendIPConfiguration.ID, *fipConfigID) {
+			if !az.serviceOwnsRule(service, *lbRule.Name) {
+				warningMsg := fmt.Sprintf("isFrontendIPConfigIsUnsafeToDelete: frontend IP configuration with ID %s on LB %s cannot be deleted because it is being referenced by load balancing rules of other services", *fipConfigID, *lb.Name)
+				klog.Warning(warningMsg)
+				az.Event(service, v1.EventTypeWarning, "DeletingFrontendIPConfiguration", warningMsg)
+				unsafe = true
+				break
+			}
+		}
+	}
+
+	// check if there are outbound rules
+	// referencing this frontend IP configuration
+	for _, outboundRule := range outboundRules {
+		if outboundRule.OutboundRulePropertiesFormat != nil && outboundRule.FrontendIPConfigurations != nil {
+			outboundRuleFIPConfigs := *outboundRule.FrontendIPConfigurations
+			if found := findMatchedOutboundRuleFIPConfig(fipConfigID, outboundRuleFIPConfigs); found {
+				warningMsg := fmt.Sprintf("isFrontendIPConfigIsUnsafeToDelete: frontend IP configuration with ID %s on LB %s cannot be deleted because it is being referenced by the outbound rule %s", *fipConfigID, *lb.Name, *outboundRule.Name)
+				klog.Warning(warningMsg)
+				az.Event(service, v1.EventTypeWarning, "DeletingFrontendIPConfiguration", warningMsg)
+				unsafe = true
+				break
+			}
+		}
+	}
+
+	// check if there are inbound NAT rules
+	// referencing this frontend IP configuration
+	for _, inboundNatRule := range inboundNatRules {
+		if inboundNatRule.InboundNatRulePropertiesFormat != nil &&
+			inboundNatRule.FrontendIPConfiguration != nil &&
+			inboundNatRule.FrontendIPConfiguration.ID != nil &&
+			strings.EqualFold(*inboundNatRule.FrontendIPConfiguration.ID, *fipConfigID) {
+			warningMsg := fmt.Sprintf("isFrontendIPConfigIsUnsafeToDelete: frontend IP configuration with ID %s on LB %s cannot be deleted because it is being referenced by the inbound NAT rule %s", *fipConfigID, *lb.Name, *inboundNatRule.Name)
+			klog.Warning(warningMsg)
+			az.Event(service, v1.EventTypeWarning, "DeletingFrontendIPConfiguration", warningMsg)
+			unsafe = true
+			break
+		}
+	}
+
+	// check if there are inbound NAT pools
+	// referencing this frontend IP configuration
+	for _, inboundNatPool := range inboundNatPools {
+		if inboundNatPool.InboundNatPoolPropertiesFormat != nil &&
+			inboundNatPool.FrontendIPConfiguration != nil &&
+			inboundNatPool.FrontendIPConfiguration.ID != nil &&
+			strings.EqualFold(*inboundNatPool.FrontendIPConfiguration.ID, *fipConfigID) {
+			warningMsg := fmt.Sprintf("isFrontendIPConfigIsUnsafeToDelete: frontend IP configuration with ID %s on LB %s cannot be deleted because it is being referenced by the inbound NAT pool %s", *fipConfigID, *lb.Name, *inboundNatPool.Name)
+			klog.Warning(warningMsg)
+			az.Event(service, v1.EventTypeWarning, "DeletingFrontendIPConfiguration", warningMsg)
+			unsafe = true
+			break
+		}
+	}
+
+	return unsafe, nil
+}
+
+func findMatchedOutboundRuleFIPConfig(fipConfigID *string, outboundRuleFIPConfigs []network.SubResource) bool {
+	var found bool
+	for _, config := range outboundRuleFIPConfigs {
+		if config.ID != nil && strings.EqualFold(*config.ID, *fipConfigID) {
+			found = true
+		}
+	}
+	return found
+}
+
+func (az *Cloud) findFrontendIPConfigOfService(
+	fipConfigs *[]network.FrontendIPConfiguration,
+	service *v1.Service,
+) (*network.FrontendIPConfiguration, bool, error) {
+	for _, config := range *fipConfigs {
+		owns, isPrimaryService, err := az.serviceOwnsFrontendIP(config, service)
+		if err != nil {
+			return nil, false, err
+		}
+		if owns {
+			return &config, isPrimaryService, nil
+		}
+	}
+
+	return nil, false, nil
+}
+
 // This ensures load balancer exists and the frontend ip config is setup.
 // This also reconciles the Service's Ports  with the LoadBalancer config.
 // This entails adding rules/probes for expected Ports and removing stale rules/ports.
@@ -792,8 +998,8 @@ func (az *Cloud) reconcileLoadBalancer(clusterName string, service *v1.Service,
 	lbName := *lb.Name
 	lbResourceGroup := az.getLoadBalancerResourceGroup()
 	klog.V(2).Infof("reconcileLoadBalancer for service(%s): lb(%s/%s) wantLb(%t) resolved load balancer name", serviceName, lbResourceGroup, lbName, wantLb)
-	lbFrontendIPConfigName := az.getFrontendIPConfigName(service)
+	defaultLBFrontendIPConfigName := az.getDefaultFrontendIPConfigName(service)
-	lbFrontendIPConfigID := az.getFrontendIPConfigID(lbName, lbResourceGroup, lbFrontendIPConfigName)
+	defaultLBFrontendIPConfigID := az.getFrontendIPConfigID(lbName, lbResourceGroup, defaultLBFrontendIPConfigName)
 	lbBackendPoolName := getBackendPoolName(clusterName, service)
 	lbBackendPoolID := az.getBackendPoolID(lbName, lbResourceGroup, lbBackendPoolName)
 
@@ -847,19 +1053,44 @@ func (az *Cloud) reconcileLoadBalancer(clusterName string, service *v1.Service,
 		newConfigs = *lb.FrontendIPConfigurations
 	}
 
+	var ownedFIPConfig *network.FrontendIPConfiguration
 	if !wantLb {
 		for i := len(newConfigs) - 1; i >= 0; i-- {
 			config := newConfigs[i]
-			if az.serviceOwnsFrontendIP(config, service) {
+			isServiceOwnsFrontendIP, _, err := az.serviceOwnsFrontendIP(config, service)
-				klog.V(2).Infof("reconcileLoadBalancer for service (%s)(%t): lb frontendconfig(%s) - dropping", serviceName, wantLb, lbFrontendIPConfigName)
+			if err != nil {
+				return nil, err
+			}
+			if isServiceOwnsFrontendIP {
+				unsafe, err := az.isFrontendIPConfigIsUnsafeToDelete(lb, service, config.ID)
+				if err != nil {
+					return nil, err
+				}
+
+				// If the frontend IP configuration is not being referenced by:
+				// 1. loadBalancing rules of other services with different ports;
+				// 2. outbound rules;
+				// 3. inbound NAT rules;
+				// 4. inbound NAT pools,
+				// do the deletion, or skip it.
+				if !unsafe {
+					var configNameToBeDeleted string
+					if newConfigs[i].Name != nil {
+						configNameToBeDeleted = *newConfigs[i].Name
+						klog.V(2).Infof("reconcileLoadBalancer for service (%s)(%t): lb frontendconfig(%s) - dropping", serviceName, wantLb, configNameToBeDeleted)
+					} else {
+						klog.V(2).Infof("reconcileLoadBalancer for service (%s)(%t): nil name of lb frontendconfig", serviceName, wantLb)
+					}
+
 					newConfigs = append(newConfigs[:i], newConfigs[i+1:]...)
 					dirtyConfigs = true
 				}
 			}
+		}
 	} else {
 		for i := len(newConfigs) - 1; i >= 0; i-- {
 			config := newConfigs[i]
-			isFipChanged, err := az.isFrontendIPChanged(clusterName, config, service, lbFrontendIPConfigName)
+			isFipChanged, err := az.isFrontendIPChanged(clusterName, config, service, defaultLBFrontendIPConfigName)
 			if err != nil {
 				return nil, err
 			}
@@ -869,14 +1100,15 @@ func (az *Cloud) reconcileLoadBalancer(clusterName string, service *v1.Service,
 				dirtyConfigs = true
 			}
 		}
-		foundConfig := false
+
-		for _, config := range newConfigs {
+		ownedFIPConfig, _, err = az.findFrontendIPConfigOfService(&newConfigs, service)
-			if strings.EqualFold(*config.Name, lbFrontendIPConfigName) {
+		if err != nil {
-				foundConfig = true
+			return nil, err
-				break
 		}
-		}
+
-		if !foundConfig {
+		if ownedFIPConfig == nil {
+			klog.V(4).Infof("ensure(%s): lb(%s) - creating a new frontend IP config", serviceName, lbName)
+
 			// construct FrontendIPConfigurationPropertiesFormat
 			var fipConfigurationProperties *network.FrontendIPConfigurationPropertiesFormat
 			if isInternal {
@@ -931,10 +1163,11 @@ func (az *Cloud) reconcileLoadBalancer(clusterName string, service *v1.Service,
 
 			newConfigs = append(newConfigs,
 				network.FrontendIPConfiguration{
-					Name:                                    to.StringPtr(lbFrontendIPConfigName),
+					Name:                                    to.StringPtr(defaultLBFrontendIPConfigName),
+					ID:                                      to.StringPtr(fmt.Sprintf(frontendIPConfigIDTemplate, az.SubscriptionID, az.ResourceGroup, *lb.Name, defaultLBFrontendIPConfigName)),
 					FrontendIPConfigurationPropertiesFormat: fipConfigurationProperties,
 				})
-			klog.V(10).Infof("reconcileLoadBalancer for service (%s)(%t): lb frontendconfig(%s) - adding", serviceName, wantLb, lbFrontendIPConfigName)
+			klog.Infof("reconcileLoadBalancer for service (%s)(%t): lb frontendconfig(%s) - adding", serviceName, wantLb, defaultLBFrontendIPConfigName)
 			dirtyConfigs = true
 		}
 	}
@@ -944,7 +1177,22 @@ func (az *Cloud) reconcileLoadBalancer(clusterName string, service *v1.Service,
 	}
 
 	// update probes/rules
-	expectedProbes, expectedRules, err := az.reconcileLoadBalancerRule(service, wantLb, lbFrontendIPConfigID, lbBackendPoolID, lbName, lbIdleTimeout)
+	if ownedFIPConfig != nil {
+		if ownedFIPConfig.ID != nil {
+			defaultLBFrontendIPConfigID = *ownedFIPConfig.ID
+		} else {
+			return nil, fmt.Errorf("reconcileLoadBalancer for service (%s)(%t): nil ID for frontend IP config", serviceName, wantLb)
+		}
+	}
+
+	if wantLb {
+		err = az.checkLoadBalancerResourcesConflicted(lb, defaultLBFrontendIPConfigID, service)
+		if err != nil {
+			return nil, err
+		}
+	}
+
+	expectedProbes, expectedRules, err := az.reconcileLoadBalancerRule(service, wantLb, defaultLBFrontendIPConfigID, lbBackendPoolID, lbName, lbIdleTimeout)
 	if err != nil {
 		return nil, err
 	}
@@ -995,6 +1243,7 @@ func (az *Cloud) reconcileLoadBalancer(clusterName string, service *v1.Service,
 	if lb.LoadBalancingRules != nil {
 		updatedRules = *lb.LoadBalancingRules
 	}
+
 	// update rules: remove unwanted
 	for i := len(updatedRules) - 1; i >= 0; i-- {
 		existingRule := updatedRules[i]
@@ -1036,7 +1285,7 @@ func (az *Cloud) reconcileLoadBalancer(clusterName string, service *v1.Service,
 	if dirtyLb {
 		if lb.FrontendIPConfigurations == nil || len(*lb.FrontendIPConfigurations) == 0 {
 			if isBackendPoolPreConfigured {
-				klog.V(2).Infof("reconcileLoadBalancer for service(%s): lb(%s) - ignore cleanup of dirty lb because the lb is pre-confiruged", serviceName, lbName)
+				klog.V(2).Infof("reconcileLoadBalancer for service(%s): lb(%s) - ignore cleanup of dirty lb because the lb is pre-configured", serviceName, lbName)
 			} else {
 				// When FrontendIPConfigurations is empty, we need to delete the Azure load balancer resource itself,
 				// because an Azure load balancer cannot have an empty FrontendIPConfigurations collection
@@ -1099,6 +1348,95 @@ func (az *Cloud) reconcileLoadBalancer(clusterName string, service *v1.Service,
 	return lb, nil
 }
 
+// checkLoadBalancerResourcesConflicted checks if the service is consuming
+// ports which are conflicted with the existing loadBalancer resources,
+// including inbound NAT rule, inbound NAT pools and loadBalancing rules
+func (az *Cloud) checkLoadBalancerResourcesConflicted(
+	lb *network.LoadBalancer,
+	frontendIPConfigID string,
+	service *v1.Service,
+) error {
+	if service.Spec.Ports == nil {
+		return nil
+	}
+	ports := service.Spec.Ports
+
+	for _, port := range ports {
+		if lb.LoadBalancingRules != nil {
+			for _, rule := range *lb.LoadBalancingRules {
+				if rule.LoadBalancingRulePropertiesFormat != nil &&
+					rule.FrontendIPConfiguration != nil &&
+					rule.FrontendIPConfiguration.ID != nil &&
+					strings.EqualFold(*rule.FrontendIPConfiguration.ID, frontendIPConfigID) &&
+					strings.EqualFold(string(rule.Protocol), string(port.Protocol)) &&
+					rule.FrontendPort != nil &&
+					*rule.FrontendPort == port.Port {
+					// ignore self-owned rules for unit test
+					if rule.Name != nil && az.serviceOwnsRule(service, *rule.Name) {
+						continue
+					}
+					return fmt.Errorf("checkLoadBalancerResourcesConflicted: service port %s is trying to "+
+						"consume the port %d which is being referenced by an existing loadBalancing rule %s with "+
+						"the same protocol %s and frontend IP config with ID %s",
+						port.Name,
+						*rule.FrontendPort,
+						*rule.Name,
+						rule.Protocol,
+						*rule.FrontendIPConfiguration.ID)
+				}
+			}
+		}
+
+		if lb.InboundNatRules != nil {
+			for _, inboundNatRule := range *lb.InboundNatRules {
+				if inboundNatRule.InboundNatRulePropertiesFormat != nil &&
+					inboundNatRule.FrontendIPConfiguration != nil &&
+					inboundNatRule.FrontendIPConfiguration.ID != nil &&
+					strings.EqualFold(*inboundNatRule.FrontendIPConfiguration.ID, frontendIPConfigID) &&
+					strings.EqualFold(string(inboundNatRule.Protocol), string(port.Protocol)) &&
+					inboundNatRule.FrontendPort != nil &&
+					*inboundNatRule.FrontendPort == port.Port {
+					return fmt.Errorf("checkLoadBalancerResourcesConflicted: service port %s is trying to "+
+						"consume the port %d which is being referenced by an existing inbound NAT rule %s with "+
+						"the same protocol %s and frontend IP config with ID %s",
+						port.Name,
+						*inboundNatRule.FrontendPort,
+						*inboundNatRule.Name,
+						inboundNatRule.Protocol,
+						*inboundNatRule.FrontendIPConfiguration.ID)
+				}
+			}
+		}
+
+		if lb.InboundNatPools != nil {
+			for _, pool := range *lb.InboundNatPools {
+				if pool.InboundNatPoolPropertiesFormat != nil &&
+					pool.FrontendIPConfiguration != nil &&
+					pool.FrontendIPConfiguration.ID != nil &&
+					strings.EqualFold(*pool.FrontendIPConfiguration.ID, frontendIPConfigID) &&
+					strings.EqualFold(string(pool.Protocol), string(port.Protocol)) &&
+					pool.FrontendPortRangeStart != nil &&
+					pool.FrontendPortRangeEnd != nil &&
+					*pool.FrontendPortRangeStart <= port.Port &&
+					*pool.FrontendPortRangeEnd >= port.Port {
+					return fmt.Errorf("checkLoadBalancerResourcesConflicted: service port %s is trying to "+
+						"consume the port %d which is being in the range (%d-%d) of an existing "+
+						"inbound NAT pool %s with the same protocol %s and frontend IP config with ID %s",
+						port.Name,
+						port.Port,
+						*pool.FrontendPortRangeStart,
+						*pool.FrontendPortRangeEnd,
+						*pool.Name,
+						pool.Protocol,
+						*pool.FrontendIPConfiguration.ID)
+				}
+			}
+		}
+	}
+
+	return nil
+}
+
 func (az *Cloud) reconcileLoadBalancerRule(
 	service *v1.Service,
 	wantLb bool,
@@ -1561,7 +1899,7 @@ func deduplicate(collection *[]string) *[]string {
 }
 
 // Determine if we should release existing owned public IPs
-func shouldReleaseExistingOwnedPublicIP(existingPip *network.PublicIPAddress, lbShouldExist bool, lbIsInternal bool, desiredPipName string, ipTagRequest serviceIPTagRequest) bool {
+func shouldReleaseExistingOwnedPublicIP(existingPip *network.PublicIPAddress, lbShouldExist, lbIsInternal bool, desiredPipName, svcName string, ipTagRequest serviceIPTagRequest) bool {
 	// Latch some variables for readability purposes.
 	pipName := *(*existingPip).Name
 
@@ -1572,6 +1910,20 @@ func shouldReleaseExistingOwnedPublicIP(existingPip *network.PublicIPAddress, lb
 		currentIPTags = (*pipPropertiesFormat).IPTags
 	}
 
+	// Check whether the public IP is being referenced by other service.
+	// The owned public IP can be released only when there is not other service using it.
+	if existingPip.Tags[serviceTagKey] != nil {
+		// case 1: there is at least one reference when deleting the PIP
+		if !lbShouldExist && len(parsePIPServiceTag(existingPip.Tags[serviceTagKey])) > 0 {
+			return false
+		}
+
+		// case 2: there is at least one reference from other service
+		if lbShouldExist && len(parsePIPServiceTag(existingPip.Tags[serviceTagKey])) > 1 {
+			return false
+		}
+	}
+
 	// Release the ip under the following criteria -
 	// #1 - If we don't actually want a load balancer,
 	return !lbShouldExist ||
@@ -1588,10 +1940,14 @@ func (az *Cloud) reconcilePublicIP(clusterName string, service *v1.Service, lbNa
 	isInternal := requiresInternalLoadBalancer(service)
 	serviceName := getServiceName(service)
 	serviceIPTagRequest := getServiceIPTagRequestForPublicIP(service)
-	var lb *network.LoadBalancer
+
-	var desiredPipName string
+	var (
-	var err error
+		lb               *network.LoadBalancer
-	var shouldPIPExisted bool
+		desiredPipName   string
+		err              error
+		shouldPIPExisted bool
+	)
+
 	if !isInternal && wantLb {
 		desiredPipName, shouldPIPExisted, err = az.determinePublicIPName(clusterName, service)
 		if err != nil {
@@ -1614,10 +1970,14 @@ func (az *Cloud) reconcilePublicIP(clusterName string, service *v1.Service, lbNa
 		return nil, err
 	}
 
-	var serviceAnnotationRequestsNamedPublicIP bool = shouldPIPExisted
+	var (
-	var discoveredDesiredPublicIP bool
+		serviceAnnotationRequestsNamedPublicIP = shouldPIPExisted
-	var deletedDesiredPublicIP bool
+		discoveredDesiredPublicIP              bool
-	var pipsToBeDeleted []*network.PublicIPAddress
+		deletedDesiredPublicIP                 bool
+		pipsToBeDeleted                        []*network.PublicIPAddress
+		pipsToBeUpdated                        []*network.PublicIPAddress
+	)
+
 	for i := range pips {
 		pip := pips[i]
 		pipName := *pip.Name
@@ -1628,9 +1988,17 @@ func (az *Cloud) reconcilePublicIP(clusterName string, service *v1.Service, lbNa
 
 		// Now, let's perform additional analysis to determine if we should release the public ips we have found.
 		// We can only let them go if (a) they are owned by this service and (b) they meet the criteria for deletion.
-		if serviceOwnsPublicIP(&pip, clusterName, serviceName) &&
+		if serviceOwnsPublicIP(&pip, clusterName, serviceName) {
-			shouldReleaseExistingOwnedPublicIP(&pip, wantLb, isInternal, desiredPipName, serviceIPTagRequest) {
+			var dirtyPIP bool
-
+			if !wantLb {
+				klog.V(2).Infof("reconcilePublicIP for service(%s): unbinding the service from pip %s", serviceName, *pip.Name)
+				err = unbindServiceFromPIP(&pip, serviceName)
+				if err != nil {
+					return nil, err
+				}
+				dirtyPIP = true
+			}
+			if shouldReleaseExistingOwnedPublicIP(&pip, wantLb, isInternal, desiredPipName, serviceName, serviceIPTagRequest) {
 				// Then, release the public ip
 				pipsToBeDeleted = append(pipsToBeDeleted, &pip)
 
@@ -1641,13 +2009,31 @@ func (az *Cloud) reconcilePublicIP(clusterName string, service *v1.Service, lbNa
 				// in Service annotations (which is usually reserved for non-service-owned externals), if that IP is tagged as
 				// having been owned by a particular Kubernetes cluster.
 			}
+
+			// Update tags of PIP only instead of deleting it.
+			if dirtyPIP {
+				pipsToBeUpdated = append(pipsToBeUpdated, &pip)
+			}
+		}
 	}
 
 	if !isInternal && serviceAnnotationRequestsNamedPublicIP && !discoveredDesiredPublicIP && wantLb {
 		return nil, fmt.Errorf("reconcilePublicIP for service(%s): pip(%s) not found", serviceName, desiredPipName)
 	}
 
-	var deleteFuncs []func() error
+	var deleteFuncs, updateFuncs []func() error
+	for _, pip := range pipsToBeUpdated {
+		pipCopy := *pip
+		updateFuncs = append(updateFuncs, func() error {
+			klog.V(2).Infof("reconcilePublicIP for service(%s): pip(%s) - updating", serviceName, *pip.Name)
+			return az.CreateOrUpdatePIP(service, pipResourceGroup, pipCopy)
+		})
+	}
+	errs := utilerrors.AggregateGoroutines(updateFuncs...)
+	if errs != nil {
+		return nil, utilerrors.Flatten(errs)
+	}
+
 	for _, pip := range pipsToBeDeleted {
 		pipCopy := *pip
 		deleteFuncs = append(deleteFuncs, func() error {
@@ -1655,7 +2041,7 @@ func (az *Cloud) reconcilePublicIP(clusterName string, service *v1.Service, lbNa
 			return az.safeDeletePublicIP(service, pipResourceGroup, &pipCopy, lb)
 		})
 	}
-	errs := utilerrors.AggregateGoroutines(deleteFuncs...)
+	errs = utilerrors.AggregateGoroutines(deleteFuncs...)
 	if errs != nil {
 		return nil, utilerrors.Flatten(errs)
 	}
@@ -1935,7 +2321,7 @@ func serviceOwnsPublicIP(pip *network.PublicIPAddress, clusterName, serviceName
 		serviceTag := pip.Tags[serviceTagKey]
 		clusterTag := pip.Tags[clusterNameKey]
 
-		if serviceTag != nil && *serviceTag == serviceName {
+		if serviceTag != nil && isSVCNameInPIPTag(*serviceTag, serviceName) {
 			// Backward compatible for clusters upgraded from old releases.
 			// In such case, only "service" tag is set.
 			if clusterTag == nil {
@@ -1948,5 +2334,119 @@ func serviceOwnsPublicIP(pip *network.PublicIPAddress, clusterName, serviceName
 			}
 		}
 	}
+
 	return false
 }
+
+func isSVCNameInPIPTag(tag, svcName string) bool {
+	svcNames := parsePIPServiceTag(&tag)
+
+	for _, name := range svcNames {
+		if strings.EqualFold(name, svcName) {
+			return true
+		}
+	}
+
+	return false
+}
+
+func parsePIPServiceTag(serviceTag *string) []string {
+	if serviceTag == nil {
+		return []string{}
+	}
+
+	serviceNames := strings.FieldsFunc(*serviceTag, func(r rune) bool {
+		return r == ','
+	})
+	for i, name := range serviceNames {
+		serviceNames[i] = strings.TrimSpace(name)
+	}
+
+	return serviceNames
+}
+
+// bindServicesToPIP add the incoming service name to the PIP's tag
+// parameters: public IP address to be updated and incoming service names
+// return values:
+// 1. a bool flag to indicate if there is a new service added
+// 2. an error when the pip is nil
+// example:
+// "ns1/svc1" + ["ns1/svc1", "ns2/svc2"] = "ns1/svc1,ns2/svc2"
+func bindServicesToPIP(pip *network.PublicIPAddress, incomingServiceNames []string, replace bool) (bool, error) {
+	if pip == nil {
+		return false, fmt.Errorf("nil public IP")
+	}
+
+	if pip.Tags == nil {
+		pip.Tags = map[string]*string{serviceTagKey: to.StringPtr("")}
+	}
+
+	serviceTagValue := pip.Tags[serviceTagKey]
+	serviceTagValueSet := make(map[string]struct{})
+	existingServiceNames := parsePIPServiceTag(serviceTagValue)
+	addedNew := false
+
+	// replace is used when unbinding the service from PIP so addedNew remains false all the time
+	if replace {
+		serviceTagValue = to.StringPtr(strings.Join(incomingServiceNames, ","))
+		pip.Tags[serviceTagKey] = serviceTagValue
+
+		return false, nil
+	}
+
+	for _, name := range existingServiceNames {
+		if _, ok := serviceTagValueSet[name]; !ok {
+			serviceTagValueSet[name] = struct{}{}
+		}
+	}
+
+	for _, serviceName := range incomingServiceNames {
+		if serviceTagValue == nil || *serviceTagValue == "" {
+			serviceTagValue = to.StringPtr(serviceName)
+			addedNew = true
+		} else {
+			// detect duplicates
+			if _, ok := serviceTagValueSet[serviceName]; !ok {
+				*serviceTagValue += fmt.Sprintf(",%s", serviceName)
+				addedNew = true
+			} else {
+				klog.V(10).Infof("service %s has been bound to the pip already", serviceName)
+			}
+		}
+	}
+	pip.Tags[serviceTagKey] = serviceTagValue
+
+	return addedNew, nil
+}
+
+func unbindServiceFromPIP(pip *network.PublicIPAddress, serviceName string) error {
+	if pip == nil || pip.Tags == nil {
+		return fmt.Errorf("nil public IP or tags")
+	}
+
+	serviceTagValue := pip.Tags[serviceTagKey]
+	existingServiceNames := parsePIPServiceTag(serviceTagValue)
+	var found bool
+	for i := len(existingServiceNames) - 1; i >= 0; i-- {
+		if strings.EqualFold(existingServiceNames[i], serviceName) {
+			existingServiceNames = append(existingServiceNames[:i], existingServiceNames[i+1:]...)
+			found = true
+		}
+	}
+	if !found {
+		klog.Warningf("cannot find the service %s in the corresponding PIP", serviceName)
+	}
+
+	_, err := bindServicesToPIP(pip, existingServiceNames, true)
+	if err != nil {
+		return err
+	}
+
+	if existingServiceName, ok := pip.Tags[serviceUsingDNSKey]; ok {
+		if strings.EqualFold(*existingServiceName, serviceName) {
+			pip.Tags[serviceUsingDNSKey] = to.StringPtr("")
+		}
+	}
+
+	return nil
+}

staging/src/k8s.io/legacy-cloud-providers/azure/azure_loadbalancer_test.go

@@ -514,6 +514,42 @@ func TestServiceOwnsPublicIP(t *testing.T) {
 			serviceName: "nginx",
 			expected:    true,
 		},
+		{
+			desc: "false should be returned when the tag is empty",
+			pip: &network.PublicIPAddress{
+				Tags: map[string]*string{
+					serviceTagKey:  to.StringPtr(""),
+					clusterNameKey: to.StringPtr("kubernetes"),
+				},
+			},
+			clusterName: "kubernetes",
+			serviceName: "nginx",
+			expected:    false,
+		},
+		{
+			desc: "true should be returned if there is a match among a multi-service tag",
+			pip: &network.PublicIPAddress{
+				Tags: map[string]*string{
+					serviceTagKey:  to.StringPtr("nginx1,nginx2"),
+					clusterNameKey: to.StringPtr("kubernetes"),
+				},
+			},
+			clusterName: "kubernetes",
+			serviceName: "nginx1",
+			expected:    true,
+		},
+		{
+			desc: "false should be returned if there is not a match among a multi-service tag",
+			pip: &network.PublicIPAddress{
+				Tags: map[string]*string{
+					serviceTagKey:  to.StringPtr("default/nginx1,default/nginx2"),
+					clusterNameKey: to.StringPtr("kubernetes"),
+				},
+			},
+			clusterName: "kubernetes",
+			serviceName: "nginx3",
+			expected:    false,
+		},
 	}
 
 	for i, c := range tests {
@@ -537,12 +573,12 @@ func TestGetPublicIPAddressResourceGroup(t *testing.T) {
 			expected: "rg",
 		},
 		{
-			desc:        "annoation with empty string resource group",
+			desc:        "annotation with empty string resource group",
 			annotations: map[string]string{ServiceAnnotationLoadBalancerResourceGroup: ""},
 			expected:    "rg",
 		},
 		{
-			desc:        "annoation with non-empty resource group ",
+			desc:        "annotation with non-empty resource group ",
 			annotations: map[string]string{ServiceAnnotationLoadBalancerResourceGroup: "rg2"},
 			expected:    "rg2",
 		},
@@ -560,7 +596,6 @@ func TestShouldReleaseExistingOwnedPublicIP(t *testing.T) {
 	existingPipWithTag := network.PublicIPAddress{
 		ID:   to.StringPtr("/subscriptions/subscription/resourceGroups/rg/providers/Microsoft.Network/publicIPAddresses/testPIP"),
 		Name: to.StringPtr("testPIP"),
-		Tags: map[string]*string{"service": to.StringPtr("default/test1")},
 		PublicIPAddressPropertiesFormat: &network.PublicIPAddressPropertiesFormat{
 			PublicIPAddressVersion:   network.IPv4,
 			PublicIPAllocationMethod: network.Static,
@@ -576,7 +611,7 @@ func TestShouldReleaseExistingOwnedPublicIP(t *testing.T) {
 	existingPipWithNoPublicIPAddressFormatProperties := network.PublicIPAddress{
 		ID:                              to.StringPtr("/subscriptions/subscription/resourceGroups/rg/providers/Microsoft.Network/publicIPAddresses/testPIP"),
 		Name:                            to.StringPtr("testPIP"),
-		Tags:                            map[string]*string{"service": to.StringPtr("default/test1")},
+		Tags:                            map[string]*string{"service": to.StringPtr("default/test2")},
 		PublicIPAddressPropertiesFormat: nil,
 	}
 
@@ -682,7 +717,7 @@ func TestShouldReleaseExistingOwnedPublicIP(t *testing.T) {
 
 	for i, c := range tests {
 
-		actualShouldRelease := shouldReleaseExistingOwnedPublicIP(&c.existingPip, c.lbShouldExist, c.lbIsInternal, c.desiredPipName, c.ipTagRequest)
+		actualShouldRelease := shouldReleaseExistingOwnedPublicIP(&c.existingPip, c.lbShouldExist, c.lbIsInternal, c.desiredPipName, "default/test1", c.ipTagRequest)
 		assert.Equal(t, c.expectedShouldRelease, actualShouldRelease, "TestCase[%d]: %s", i, c.desc)
 	}
 }
@@ -1357,7 +1392,9 @@ func TestIsFrontendIPChanged(t *testing.T) {
 			config: network.FrontendIPConfiguration{
 				Name: to.StringPtr("btest1-name"),
 				FrontendIPConfigurationPropertiesFormat: &network.FrontendIPConfigurationPropertiesFormat{
-					PublicIPAddress: nil,
+					PublicIPAddress: &network.PublicIPAddress{
+						ID: to.StringPtr("pip"),
+					},
 				},
 			},
 			lbFrontendIPConfigName: "btest1-name",
@@ -1366,6 +1403,7 @@ func TestIsFrontendIPChanged(t *testing.T) {
 			existingPIPs: []network.PublicIPAddress{
 				{
 					Name: to.StringPtr("pipName"),
+					ID:   to.StringPtr("pip"),
 					PublicIPAddressPropertiesFormat: &network.PublicIPAddressPropertiesFormat{
 						IPAddress: to.StringPtr("1.1.1.1"),
 					},
@@ -1404,8 +1442,10 @@ func TestIsFrontendIPChanged(t *testing.T) {
 			config: network.FrontendIPConfiguration{
 				Name: to.StringPtr("btest1-name"),
 				FrontendIPConfigurationPropertiesFormat: &network.FrontendIPConfigurationPropertiesFormat{
-					PublicIPAddress: &network.PublicIPAddress{ID: to.StringPtr("/subscriptions/subscription" +
+					PublicIPAddress: &network.PublicIPAddress{
-						"/resourceGroups/rg/providers/Microsoft.Network/publicIPAddresses/pipName1")},
+						ID: to.StringPtr("/subscriptions/subscription" +
+							"/resourceGroups/rg/providers/Microsoft.Network/publicIPAddresses/pipName1"),
+					},
 				},
 			},
 			lbFrontendIPConfigName: "btest1-name",
@@ -1414,6 +1454,8 @@ func TestIsFrontendIPChanged(t *testing.T) {
 			existingPIPs: []network.PublicIPAddress{
 				{
 					Name: to.StringPtr("pipName"),
+					ID: to.StringPtr("/subscriptions/subscription" +
+						"/resourceGroups/rg/providers/Microsoft.Network/publicIPAddresses/pipName2"),
 					PublicIPAddressPropertiesFormat: &network.PublicIPAddressPropertiesFormat{
 						IPAddress: to.StringPtr("1.1.1.1"),
 					},
@@ -1448,6 +1490,9 @@ func TestIsFrontendIPChanged(t *testing.T) {
 		test.service.Annotations[ServiceAnnotationLoadBalancerInternalSubnet] = test.annotations
 		flag, rerr := az.isFrontendIPChanged("testCluster", test.config,
 			&test.service, test.lbFrontendIPConfigName)
+		if rerr != nil {
+			fmt.Println(rerr.Error())
+		}
 		assert.Equal(t, test.expectedFlag, flag, "TestCase[%d]: %s", i, test.desc)
 		assert.Equal(t, test.expectedError, rerr != nil, "TestCase[%d]: %s", i, test.desc)
 	}
@@ -1684,6 +1729,7 @@ func getTestLoadBalancer(name, rgName, clusterName, identifier *string, service
 			FrontendIPConfigurations: &[]network.FrontendIPConfiguration{
 				{
 					Name: identifier,
+					ID:   identifier,
 					FrontendIPConfigurationPropertiesFormat: &network.FrontendIPConfigurationPropertiesFormat{
 						PublicIPAddress: &network.PublicIPAddress{ID: to.StringPtr("testCluster-aservice1")},
 					},
@@ -1745,6 +1791,7 @@ func TestReconcileLoadBalancer(t *testing.T) {
 	basicLb2.FrontendIPConfigurations = &[]network.FrontendIPConfiguration{
 		{
 			Name: to.StringPtr("bservice1"),
+			ID:   to.StringPtr("bservice1"),
 			FrontendIPConfigurationPropertiesFormat: &network.FrontendIPConfigurationPropertiesFormat{
 				PublicIPAddress: &network.PublicIPAddress{ID: to.StringPtr("testCluster-bservice1")},
 			},
@@ -1756,12 +1803,14 @@ func TestReconcileLoadBalancer(t *testing.T) {
 	modifiedLb1.FrontendIPConfigurations = &[]network.FrontendIPConfiguration{
 		{
 			Name: to.StringPtr("aservice1"),
+			ID:   to.StringPtr("/subscriptions/subscription/resourceGroups/rg/providers/Microsoft.Network/loadBalancers/testCluster/frontendIPConfigurations/aservice1"),
 			FrontendIPConfigurationPropertiesFormat: &network.FrontendIPConfigurationPropertiesFormat{
 				PublicIPAddress: &network.PublicIPAddress{ID: to.StringPtr("testCluster-aservice1")},
 			},
 		},
 		{
 			Name: to.StringPtr("bservice1"),
+			ID:   to.StringPtr("bservice1"),
 			FrontendIPConfigurationPropertiesFormat: &network.FrontendIPConfigurationPropertiesFormat{
 				PublicIPAddress: &network.PublicIPAddress{ID: to.StringPtr("testCluster-bservice1")},
 			},
@@ -1789,12 +1838,14 @@ func TestReconcileLoadBalancer(t *testing.T) {
 	expectedLb1.FrontendIPConfigurations = &[]network.FrontendIPConfiguration{
 		{
 			Name: to.StringPtr("aservice1"),
+			ID:   to.StringPtr("/subscriptions/subscription/resourceGroups/rg/providers/Microsoft.Network/loadBalancers/testCluster/frontendIPConfigurations/aservice1"),
 			FrontendIPConfigurationPropertiesFormat: &network.FrontendIPConfigurationPropertiesFormat{
 				PublicIPAddress: &network.PublicIPAddress{ID: to.StringPtr("testCluster-aservice1")},
 			},
 		},
 		{
 			Name: to.StringPtr("bservice1"),
+			ID:   to.StringPtr("bservice1"),
 			FrontendIPConfigurationPropertiesFormat: &network.FrontendIPConfigurationPropertiesFormat{
 				PublicIPAddress: &network.PublicIPAddress{ID: to.StringPtr("testCluster-bservice1")},
 			},
@@ -1806,12 +1857,14 @@ func TestReconcileLoadBalancer(t *testing.T) {
 	existingSLB.FrontendIPConfigurations = &[]network.FrontendIPConfiguration{
 		{
 			Name: to.StringPtr("aservice1"),
+			ID:   to.StringPtr("/subscriptions/subscription/resourceGroups/rg/providers/Microsoft.Network/loadBalancers/testCluster/frontendIPConfigurations/aservice1"),
 			FrontendIPConfigurationPropertiesFormat: &network.FrontendIPConfigurationPropertiesFormat{
 				PublicIPAddress: &network.PublicIPAddress{ID: to.StringPtr("testCluster-aservice1")},
 			},
 		},
 		{
 			Name: to.StringPtr("bservice1"),
+			ID:   to.StringPtr("bservice1"),
 			FrontendIPConfigurationPropertiesFormat: &network.FrontendIPConfigurationPropertiesFormat{
 				PublicIPAddress: &network.PublicIPAddress{ID: to.StringPtr("testCluster-bservice1")},
 			},
@@ -1840,12 +1893,14 @@ func TestReconcileLoadBalancer(t *testing.T) {
 	expectedSLb.FrontendIPConfigurations = &[]network.FrontendIPConfiguration{
 		{
 			Name: to.StringPtr("aservice1"),
+			ID:   to.StringPtr("/subscriptions/subscription/resourceGroups/rg/providers/Microsoft.Network/loadBalancers/testCluster/frontendIPConfigurations/aservice1"),
 			FrontendIPConfigurationPropertiesFormat: &network.FrontendIPConfigurationPropertiesFormat{
 				PublicIPAddress: &network.PublicIPAddress{ID: to.StringPtr("testCluster-aservice1")},
 			},
 		},
 		{
 			Name: to.StringPtr("bservice1"),
+			ID:   to.StringPtr("bservice1"),
 			FrontendIPConfigurationPropertiesFormat: &network.FrontendIPConfigurationPropertiesFormat{
 				PublicIPAddress: &network.PublicIPAddress{ID: to.StringPtr("testCluster-bservice1")},
 			},
@@ -1857,12 +1912,14 @@ func TestReconcileLoadBalancer(t *testing.T) {
 	slb5.FrontendIPConfigurations = &[]network.FrontendIPConfiguration{
 		{
 			Name: to.StringPtr("aservice1"),
+			ID:   to.StringPtr("/subscriptions/subscription/resourceGroups/rg/providers/Microsoft.Network/loadBalancers/testCluster/frontendIPConfigurations/aservice1"),
 			FrontendIPConfigurationPropertiesFormat: &network.FrontendIPConfigurationPropertiesFormat{
 				PublicIPAddress: &network.PublicIPAddress{ID: to.StringPtr("testCluster-aservice1")},
 			},
 		},
 		{
 			Name: to.StringPtr("bservice1"),
+			ID:   to.StringPtr("bservice1"),
 			FrontendIPConfigurationPropertiesFormat: &network.FrontendIPConfigurationPropertiesFormat{
 				PublicIPAddress: &network.PublicIPAddress{ID: to.StringPtr("testCluster-bservice1")},
 			},
@@ -1893,12 +1950,14 @@ func TestReconcileLoadBalancer(t *testing.T) {
 	expectedSLb5.FrontendIPConfigurations = &[]network.FrontendIPConfiguration{
 		{
 			Name: to.StringPtr("aservice1"),
+			ID:   to.StringPtr("/subscriptions/subscription/resourceGroups/rg/providers/Microsoft.Network/loadBalancers/testCluster/frontendIPConfigurations/aservice1"),
 			FrontendIPConfigurationPropertiesFormat: &network.FrontendIPConfigurationPropertiesFormat{
 				PublicIPAddress: &network.PublicIPAddress{ID: to.StringPtr("testCluster-aservice1")},
 			},
 		},
 		{
 			Name: to.StringPtr("bservice1"),
+			ID:   to.StringPtr("bservice1"),
 			FrontendIPConfigurationPropertiesFormat: &network.FrontendIPConfigurationPropertiesFormat{
 				PublicIPAddress: &network.PublicIPAddress{ID: to.StringPtr("testCluster-bservice1")},
 			},
@@ -1917,6 +1976,7 @@ func TestReconcileLoadBalancer(t *testing.T) {
 	expectedLB6.FrontendIPConfigurations = &[]network.FrontendIPConfiguration{
 		{
 			Name: to.StringPtr("aservice1"),
+			ID:   to.StringPtr("/subscriptions/subscription/resourceGroups/rg/providers/Microsoft.Network/loadBalancers/testCluster/frontendIPConfigurations/aservice1"),
 			FrontendIPConfigurationPropertiesFormat: &network.FrontendIPConfigurationPropertiesFormat{
 				PublicIPAddress: &network.PublicIPAddress{ID: to.StringPtr("testCluster-aservice1")},
 			},
@@ -1938,6 +1998,7 @@ func TestReconcileLoadBalancer(t *testing.T) {
 	expectedLB7.FrontendIPConfigurations = &[]network.FrontendIPConfiguration{
 		{
 			Name: to.StringPtr("aservice1"),
+			ID:   to.StringPtr("/subscriptions/subscription/resourceGroups/rg/providers/Microsoft.Network/loadBalancers/testCluster/frontendIPConfigurations/aservice1"),
 			FrontendIPConfigurationPropertiesFormat: &network.FrontendIPConfigurationPropertiesFormat{
 				PublicIPAddress: &network.PublicIPAddress{ID: to.StringPtr("testCluster-aservice1")},
 			},
@@ -1966,6 +2027,7 @@ func TestReconcileLoadBalancer(t *testing.T) {
 	expectedLB8.FrontendIPConfigurations = &[]network.FrontendIPConfiguration{
 		{
 			Name: to.StringPtr("aservice1"),
+			ID:   to.StringPtr("/subscriptions/subscription/resourceGroups/rg/providers/Microsoft.Network/loadBalancers/testCluster/frontendIPConfigurations/aservice1"),
 			FrontendIPConfigurationPropertiesFormat: &network.FrontendIPConfigurationPropertiesFormat{
 				PublicIPAddress: &network.PublicIPAddress{ID: to.StringPtr("testCluster-aservice1")},
 			},
@@ -2017,7 +2079,7 @@ func TestReconcileLoadBalancer(t *testing.T) {
 			expectedError:   nil,
 		},
 		{
-			desc:            "reconcileLoadBalancer shall remove and reconstruct the correspond field of lb",
+			desc:            "reconcileLoadBalancer shall remove and reconstruct the corresponding field of lb",
 			loadBalancerSku: "basic",
 			service:         service3,
 			existingLB:      modifiedLb1,
@@ -2036,7 +2098,7 @@ func TestReconcileLoadBalancer(t *testing.T) {
 			expectedError:   nil,
 		},
 		{
-			desc:                "reconcileLoadBalancer shall remove and reconstruct the correspoind field of lb and set enableTcpReset to true in lbRule",
+			desc:                "reconcileLoadBalancer shall remove and reconstruct the corresponding field of lb and set enableTcpReset to true in lbRule",
 			loadBalancerSku:     "standard",
 			service:             service4,
 			disableOutboundSnat: to.BoolPtr(true),
@@ -2046,7 +2108,7 @@ func TestReconcileLoadBalancer(t *testing.T) {
 			expectedError:       nil,
 		},
 		{
-			desc:                "reconcileLoadBalancer shall remove and reconstruct the correspoind field of lb and set enableTcpReset (false => true) in lbRule",
+			desc:                "reconcileLoadBalancer shall remove and reconstruct the corresponding field of lb and set enableTcpReset (false => true) in lbRule",
 			loadBalancerSku:     "standard",
 			service:             service5,
 			disableOutboundSnat: to.BoolPtr(true),
@@ -2124,7 +2186,7 @@ func TestReconcileLoadBalancer(t *testing.T) {
 		assert.Equal(t, test.expectedError, rerr, "TestCase[%d]: %s", i, test.desc)
 
 		if test.expectedError == nil {
-			assert.Equal(t, &test.expectedLB, lb, "TestCase[%d]: %s", i, test.desc)
+			assert.Equal(t, test.expectedLB, *lb, "TestCase[%d]: %s", i, test.desc)
 		}
 	}
 }
@@ -2223,7 +2285,7 @@ func TestGetServiceLoadBalancerStatus(t *testing.T) {
 		},
 		{
 			desc: "getServiceLoadBalancerStatus shall return nil if lb.FrontendIPConfigurations.name != " +
-				"az.getFrontendIPConfigName(service)",
+				"az.getDefaultFrontendIPConfigName(service)",
 			service: &internalService,
 			lb:      &lb3,
 		},
@@ -2517,11 +2579,13 @@ func TestReconcilePublicIP(t *testing.T) {
 		expectedPIP                 *network.PublicIPAddress
 		expectedError               bool
 		expectedCreateOrUpdateCount int
+		expectedDeleteCount         int
 	}{
 		{
 			desc:                        "reconcilePublicIP shall return nil if there's no pip in service",
 			wantLb:                      false,
 			expectedCreateOrUpdateCount: 0,
+			expectedDeleteCount:         0,
 		},
 		{
 			desc:   "reconcilePublicIP shall return nil if no pip is owned by service",
@@ -2532,6 +2596,7 @@ func TestReconcilePublicIP(t *testing.T) {
 				},
 			},
 			expectedCreateOrUpdateCount: 0,
+			expectedDeleteCount:         0,
 		},
 		{
 			desc:   "reconcilePublicIP shall delete unwanted pips and create a new one",
@@ -2545,6 +2610,7 @@ func TestReconcilePublicIP(t *testing.T) {
 			expectedID: "/subscriptions/subscription/resourceGroups/rg/providers/" +
 				"Microsoft.Network/publicIPAddresses/testCluster-atest1",
 			expectedCreateOrUpdateCount: 1,
+			expectedDeleteCount:         1,
 		},
 		{
 			desc:        "reconcilePublicIP shall report error if the given PIP name doesn't exist in the resource group",
@@ -2562,6 +2628,7 @@ func TestReconcilePublicIP(t *testing.T) {
 			},
 			expectedError:               true,
 			expectedCreateOrUpdateCount: 0,
+			expectedDeleteCount:         0,
 		},
 		{
 			desc:        "reconcilePublicIP shall delete unwanted PIP when given the name of desired PIP",
@@ -2585,8 +2652,43 @@ func TestReconcilePublicIP(t *testing.T) {
 				ID:   to.StringPtr("/subscriptions/subscription/resourceGroups/rg/providers/Microsoft.Network/publicIPAddresses/testPIP"),
 				Name: to.StringPtr("testPIP"),
 				Tags: map[string]*string{"service": to.StringPtr("default/test1")},
+				PublicIPAddressPropertiesFormat: &network.PublicIPAddressPropertiesFormat{
+					PublicIPAllocationMethod: network.Static,
+					PublicIPAddressVersion:   network.IPv4,
 				},
-			expectedCreateOrUpdateCount: 0,
+			},
+			expectedCreateOrUpdateCount: 1,
+			expectedDeleteCount:         2,
+		},
+		{
+			desc:        "reconcilePublicIP shall not delete unwanted PIP when there are other service references",
+			wantLb:      true,
+			annotations: map[string]string{ServiceAnnotationPIPName: "testPIP"},
+			existingPIPs: []network.PublicIPAddress{
+				{
+					Name: to.StringPtr("pip1"),
+					Tags: map[string]*string{"service": to.StringPtr("default/test1")},
+				},
+				{
+					Name: to.StringPtr("pip2"),
+					Tags: map[string]*string{"service": to.StringPtr("default/test1,default/test2")},
+				},
+				{
+					Name: to.StringPtr("testPIP"),
+					Tags: map[string]*string{"service": to.StringPtr("default/test1")},
+				},
+			},
+			expectedPIP: &network.PublicIPAddress{
+				ID:   to.StringPtr("/subscriptions/subscription/resourceGroups/rg/providers/Microsoft.Network/publicIPAddresses/testPIP"),
+				Name: to.StringPtr("testPIP"),
+				Tags: map[string]*string{"service": to.StringPtr("default/test1")},
+				PublicIPAddressPropertiesFormat: &network.PublicIPAddressPropertiesFormat{
+					PublicIPAllocationMethod: network.Static,
+					PublicIPAddressVersion:   network.IPv4,
+				},
+			},
+			expectedCreateOrUpdateCount: 1,
+			expectedDeleteCount:         1,
 		},
 		{
 			desc:   "reconcilePublicIP shall delete unwanted pips and existing pips, when the existing pips IP tags do not match",
@@ -2625,6 +2727,7 @@ func TestReconcilePublicIP(t *testing.T) {
 				},
 			},
 			expectedCreateOrUpdateCount: 1,
+			expectedDeleteCount:         2,
 		},
 		{
 			desc:   "reconcilePublicIP shall preserve existing pips, when the existing pips IP tags do match",
@@ -2664,7 +2767,8 @@ func TestReconcilePublicIP(t *testing.T) {
 					},
 				},
 			},
-			expectedCreateOrUpdateCount: 0,
+			expectedCreateOrUpdateCount: 1,
+			expectedDeleteCount:         0,
 		},
 		{
 			desc:        "reconcilePublicIP shall find the PIP by given name and shall not delete the PIP which is not owned by service",
@@ -2685,8 +2789,24 @@ func TestReconcilePublicIP(t *testing.T) {
 			expectedPIP: &network.PublicIPAddress{
 				ID:   to.StringPtr("/subscriptions/subscription/resourceGroups/rg/providers/Microsoft.Network/publicIPAddresses/testPIP"),
 				Name: to.StringPtr("testPIP"),
+				PublicIPAddressPropertiesFormat: &network.PublicIPAddressPropertiesFormat{
+					PublicIPAllocationMethod: network.Static,
+					PublicIPAddressVersion:   network.IPv4,
 				},
-			expectedCreateOrUpdateCount: 0,
+			},
+			expectedCreateOrUpdateCount: 1,
+			expectedDeleteCount:         1,
+		},
+		{
+			desc:   "reconcilePublicIP shall delete the unwanted PIP name from service tag and shall not delete it if there is other reference",
+			wantLb: false,
+			existingPIPs: []network.PublicIPAddress{
+				{
+					Name: to.StringPtr("pip1"),
+					Tags: map[string]*string{serviceTagKey: to.StringPtr("default/test1,default/test2")},
+				},
+			},
+			expectedCreateOrUpdateCount: 1,
 		},
 	}
 
@@ -2768,6 +2888,14 @@ func TestReconcilePublicIP(t *testing.T) {
 		}
 		assert.Equal(t, test.expectedCreateOrUpdateCount, createOrUpdateCount, "TestCase[%d]: %s", i, test.desc)
 		assert.Equal(t, test.expectedError, err != nil, "TestCase[%d]: %s", i, test.desc)
+
+		deletedCount := 0
+		for _, deleted := range deletedPips {
+			if deleted {
+				deletedCount++
+			}
+		}
+		assert.Equal(t, test.expectedDeleteCount, deletedCount, "TestCase[%d]: %s", i, test.desc)
 	}
 }
 
@@ -2894,6 +3022,21 @@ func TestEnsurePublicIPExists(t *testing.T) {
 				},
 			},
 		},
+		{
+			desc:                    "ensurePublicIPExists shall report an conflict error if the DNS label is conflicted",
+			inputDNSLabel:           "test",
+			foundDNSLabelAnnotation: true,
+			existingPIPs: []network.PublicIPAddress{{
+				Name: to.StringPtr("pip1"),
+				Tags: map[string]*string{serviceUsingDNSKey: to.StringPtr("test1")},
+				PublicIPAddressPropertiesFormat: &network.PublicIPAddressPropertiesFormat{
+					DNSSettings: &network.PublicIPAddressDNSSettings{
+						DomainNameLabel: to.StringPtr("previousdns"),
+					},
+				},
+			}},
+			expectedError: true,
+		},
 	}
 
 	for i, test := range testCases {
@@ -2944,12 +3087,12 @@ func TestEnsurePublicIPExists(t *testing.T) {
 			}
 		}
 		pip, err := az.ensurePublicIPExists(&service, "pip1", test.inputDNSLabel, "", false, test.foundDNSLabelAnnotation)
+		assert.Equal(t, test.expectedError, err != nil, "TestCase[%d]: %s, encountered unexpected error: %v", i, test.desc, err)
 		if test.expectedID != "" {
 			assert.Equal(t, test.expectedID, to.String(pip.ID), "TestCase[%d]: %s", i, test.desc)
 		} else {
 			assert.Equal(t, test.expectedPIP, pip, "TestCase[%d]: %s", i, test.desc)
 		}
-		assert.Equal(t, test.expectedError, err != nil, "TestCase[%d]: %s", i, test.desc)
 	}
 }
 
@@ -3100,3 +3243,306 @@ func TestIsBackendPoolPreConfigured(t *testing.T) {
 		assert.Equal(t, test.expectedOutput, isPreConfigured, "TestCase[%d]: %s", i, test.desc)
 	}
 }
+
+func TestParsePIPServiceTag(t *testing.T) {
+	tags := []*string{
+		to.StringPtr("ns1/svc1,ns2/svc2"),
+		to.StringPtr(" ns1/svc1, ns2/svc2 "),
+		to.StringPtr("ns1/svc1,"),
+		to.StringPtr(""),
+		nil,
+	}
+	expectedNames := [][]string{
+		{"ns1/svc1", "ns2/svc2"},
+		{"ns1/svc1", "ns2/svc2"},
+		{"ns1/svc1"},
+		{},
+		{},
+	}
+
+	for i, tag := range tags {
+		names := parsePIPServiceTag(tag)
+		assert.Equal(t, expectedNames[i], names)
+	}
+}
+
+func TestBindServicesToPIP(t *testing.T) {
+	pips := []*network.PublicIPAddress{
+		{Tags: nil},
+		{Tags: map[string]*string{}},
+		{Tags: map[string]*string{serviceTagKey: to.StringPtr("ns1/svc1")}},
+		{Tags: map[string]*string{serviceTagKey: to.StringPtr("ns1/svc1,ns2/svc2")}},
+		{Tags: map[string]*string{serviceTagKey: to.StringPtr("ns2/svc2,ns3/svc3")}},
+	}
+	serviceNames := []string{"ns2/svc2", "ns3/svc3"}
+	expectedTags := []map[string]*string{
+		{serviceTagKey: to.StringPtr("ns2/svc2,ns3/svc3")},
+		{serviceTagKey: to.StringPtr("ns2/svc2,ns3/svc3")},
+		{serviceTagKey: to.StringPtr("ns1/svc1,ns2/svc2,ns3/svc3")},
+		{serviceTagKey: to.StringPtr("ns1/svc1,ns2/svc2,ns3/svc3")},
+		{serviceTagKey: to.StringPtr("ns2/svc2,ns3/svc3")},
+	}
+
+	flags := []bool{true, true, true, true, false}
+
+	for i, pip := range pips {
+		addedNew, _ := bindServicesToPIP(pip, serviceNames, false)
+		assert.Equal(t, expectedTags[i], pip.Tags)
+		assert.Equal(t, flags[i], addedNew)
+	}
+}
+
+func TestUnbindServiceFromPIP(t *testing.T) {
+	pips := []*network.PublicIPAddress{
+		{Tags: nil},
+		{Tags: map[string]*string{serviceTagKey: to.StringPtr("")}},
+		{Tags: map[string]*string{serviceTagKey: to.StringPtr("ns1/svc1")}},
+		{Tags: map[string]*string{serviceTagKey: to.StringPtr("ns1/svc1,ns2/svc2")}},
+	}
+	serviceName := "ns2/svc2"
+	expectedTags := []map[string]*string{
+		nil,
+		{serviceTagKey: to.StringPtr("")},
+		{serviceTagKey: to.StringPtr("ns1/svc1")},
+		{serviceTagKey: to.StringPtr("ns1/svc1")},
+	}
+
+	for i, pip := range pips {
+		_ = unbindServiceFromPIP(pip, serviceName)
+		assert.Equal(t, expectedTags[i], pip.Tags)
+	}
+}
+
+func TestIsFrontendIPConfigIsUnsafeToDelete(t *testing.T) {
+	ctrl := gomock.NewController(t)
+	defer ctrl.Finish()
+
+	service := getTestService("service1", v1.ProtocolTCP, nil, false, 80)
+	az := GetTestCloud(ctrl)
+	fipID := to.StringPtr("fip")
+
+	testCases := []struct {
+		desc       string
+		existingLB *network.LoadBalancer
+		unsafe     bool
+	}{
+		{
+			desc: "isFrontendIPConfigIsUnsafeToDelete should return true if there is a " +
+				"loadBalancing rule from other service referencing the frontend IP config",
+			existingLB: &network.LoadBalancer{
+				Name: to.StringPtr("lb"),
+				LoadBalancerPropertiesFormat: &network.LoadBalancerPropertiesFormat{
+					LoadBalancingRules: &[]network.LoadBalancingRule{
+						{
+							Name: to.StringPtr("aservice2-rule"),
+							LoadBalancingRulePropertiesFormat: &network.LoadBalancingRulePropertiesFormat{
+								FrontendIPConfiguration: &network.SubResource{ID: to.StringPtr("fip")},
+							},
+						},
+					},
+				},
+			},
+			unsafe: true,
+		},
+		{
+			desc: "isFrontendIPConfigIsUnsafeToDelete should return false if there is a " +
+				"loadBalancing rule from this service referencing the frontend IP config",
+			existingLB: &network.LoadBalancer{
+				Name: to.StringPtr("lb"),
+				LoadBalancerPropertiesFormat: &network.LoadBalancerPropertiesFormat{
+					OutboundRules: &[]network.OutboundRule{
+						{
+							Name: to.StringPtr("aservice1-rule"),
+							OutboundRulePropertiesFormat: &network.OutboundRulePropertiesFormat{
+								FrontendIPConfigurations: &[]network.SubResource{
+									{ID: to.StringPtr("fip")},
+								},
+							},
+						},
+					},
+				},
+			},
+			unsafe: true,
+		},
+		{
+			desc: "isFrontendIPConfigIsUnsafeToDelete should return false if there is a " +
+				"outbound rule referencing the frontend IP config",
+			existingLB: &network.LoadBalancer{
+				Name: to.StringPtr("lb"),
+				LoadBalancerPropertiesFormat: &network.LoadBalancerPropertiesFormat{
+					LoadBalancingRules: &[]network.LoadBalancingRule{
+						{
+							Name: to.StringPtr("aservice1-rule"),
+							LoadBalancingRulePropertiesFormat: &network.LoadBalancingRulePropertiesFormat{
+								FrontendIPConfiguration: &network.SubResource{ID: to.StringPtr("fip")},
+							},
+						},
+					},
+				},
+			},
+		},
+		{
+			desc: "isFrontendIPConfigIsUnsafeToDelete should return true if there is a " +
+				"inbound NAT rule referencing the frontend IP config",
+			existingLB: &network.LoadBalancer{
+				Name: to.StringPtr("lb"),
+				LoadBalancerPropertiesFormat: &network.LoadBalancerPropertiesFormat{
+					InboundNatRules: &[]network.InboundNatRule{
+						{
+							Name: to.StringPtr("aservice2-rule"),
+							InboundNatRulePropertiesFormat: &network.InboundNatRulePropertiesFormat{
+								FrontendIPConfiguration: &network.SubResource{ID: to.StringPtr("fip")},
+							},
+						},
+					},
+				},
+			},
+			unsafe: true,
+		},
+		{
+			desc: "isFrontendIPConfigIsUnsafeToDelete should return true if there is a " +
+				"inbound NAT pool referencing the frontend IP config",
+			existingLB: &network.LoadBalancer{
+				Name: to.StringPtr("lb"),
+				LoadBalancerPropertiesFormat: &network.LoadBalancerPropertiesFormat{
+					InboundNatPools: &[]network.InboundNatPool{
+						{
+							Name: to.StringPtr("aservice2-rule"),
+							InboundNatPoolPropertiesFormat: &network.InboundNatPoolPropertiesFormat{
+								FrontendIPConfiguration: &network.SubResource{ID: to.StringPtr("fip")},
+							},
+						},
+					},
+				},
+			},
+			unsafe: true,
+		},
+	}
+
+	for _, testCase := range testCases {
+		unsafe, _ := az.isFrontendIPConfigIsUnsafeToDelete(testCase.existingLB, &service, fipID)
+		assert.Equal(t, testCase.unsafe, unsafe, testCase.desc)
+	}
+}
+
+func TestCheckLoadBalancerResourcesConflicted(t *testing.T) {
+	ctrl := gomock.NewController(t)
+	defer ctrl.Finish()
+
+	service := getTestService("service1", v1.ProtocolTCP, nil, false, 80)
+	az := GetTestCloud(ctrl)
+	fipID := "fip"
+
+	testCases := []struct {
+		desc        string
+		existingLB  *network.LoadBalancer
+		expectedErr bool
+	}{
+		{
+			desc: "checkLoadBalancerResourcesConflicted should report the conflict error if " +
+				"there is a conflicted loadBalancing rule",
+			existingLB: &network.LoadBalancer{
+				Name: to.StringPtr("lb"),
+				LoadBalancerPropertiesFormat: &network.LoadBalancerPropertiesFormat{
+					LoadBalancingRules: &[]network.LoadBalancingRule{
+						{
+							Name: to.StringPtr("aservice2-rule"),
+							LoadBalancingRulePropertiesFormat: &network.LoadBalancingRulePropertiesFormat{
+								FrontendIPConfiguration: &network.SubResource{ID: to.StringPtr("fip")},
+								FrontendPort:            to.Int32Ptr(80),
+								Protocol:                network.TransportProtocol(v1.ProtocolTCP),
+							},
+						},
+					},
+				},
+			},
+			expectedErr: true,
+		},
+		{
+			desc: "checkLoadBalancerResourcesConflicted should report the conflict error if " +
+				"there is a conflicted inbound NAT rule",
+			existingLB: &network.LoadBalancer{
+				Name: to.StringPtr("lb"),
+				LoadBalancerPropertiesFormat: &network.LoadBalancerPropertiesFormat{
+					InboundNatRules: &[]network.InboundNatRule{
+						{
+							Name: to.StringPtr("aservice1-rule"),
+							InboundNatRulePropertiesFormat: &network.InboundNatRulePropertiesFormat{
+								FrontendIPConfiguration: &network.SubResource{ID: to.StringPtr("fip")},
+								FrontendPort:            to.Int32Ptr(80),
+								Protocol:                network.TransportProtocol(v1.ProtocolTCP),
+							},
+						},
+					},
+				},
+			},
+			expectedErr: true,
+		},
+		{
+			desc: "checkLoadBalancerResourcesConflicted should report the conflict error if " +
+				"there is a conflicted inbound NAT pool",
+			existingLB: &network.LoadBalancer{
+				Name: to.StringPtr("lb"),
+				LoadBalancerPropertiesFormat: &network.LoadBalancerPropertiesFormat{
+					InboundNatPools: &[]network.InboundNatPool{
+						{
+							Name: to.StringPtr("aservice1-rule"),
+							InboundNatPoolPropertiesFormat: &network.InboundNatPoolPropertiesFormat{
+								FrontendIPConfiguration: &network.SubResource{ID: to.StringPtr("fip")},
+								FrontendPortRangeStart:  to.Int32Ptr(80),
+								FrontendPortRangeEnd:    to.Int32Ptr(90),
+								Protocol:                network.TransportProtocol(v1.ProtocolTCP),
+							},
+						},
+					},
+				},
+			},
+			expectedErr: true,
+		},
+		{
+			desc: "checkLoadBalancerResourcesConflicted should not report the conflict error if there " +
+				"is no conflicted loadBalancer resources",
+			existingLB: &network.LoadBalancer{
+				Name: to.StringPtr("lb"),
+				LoadBalancerPropertiesFormat: &network.LoadBalancerPropertiesFormat{
+					LoadBalancingRules: &[]network.LoadBalancingRule{
+						{
+							Name: to.StringPtr("aservice2-rule"),
+							LoadBalancingRulePropertiesFormat: &network.LoadBalancingRulePropertiesFormat{
+								FrontendIPConfiguration: &network.SubResource{ID: to.StringPtr("fip")},
+								FrontendPort:            to.Int32Ptr(90),
+								Protocol:                network.TransportProtocol(v1.ProtocolTCP),
+							},
+						},
+					},
+					InboundNatRules: &[]network.InboundNatRule{
+						{
+							Name: to.StringPtr("aservice1-rule"),
+							InboundNatRulePropertiesFormat: &network.InboundNatRulePropertiesFormat{
+								FrontendIPConfiguration: &network.SubResource{ID: to.StringPtr("fip")},
+								FrontendPort:            to.Int32Ptr(90),
+								Protocol:                network.TransportProtocol(v1.ProtocolTCP),
+							},
+						},
+					},
+					InboundNatPools: &[]network.InboundNatPool{
+						{
+							Name: to.StringPtr("aservice1-rule"),
+							InboundNatPoolPropertiesFormat: &network.InboundNatPoolPropertiesFormat{
+								FrontendIPConfiguration: &network.SubResource{ID: to.StringPtr("fip")},
+								FrontendPortRangeStart:  to.Int32Ptr(800),
+								FrontendPortRangeEnd:    to.Int32Ptr(900),
+								Protocol:                network.TransportProtocol(v1.ProtocolTCP),
+							},
+						},
+					},
+				},
+			},
+		},
+	}
+
+	for _, testCase := range testCases {
+		err := az.checkLoadBalancerResourcesConflicted(testCase.existingLB, fipID, &service)
+		assert.Equal(t, testCase.expectedErr, err != nil, testCase.desc)
+	}
+}

staging/src/k8s.io/legacy-cloud-providers/azure/azure_standard.go

@@ -262,7 +262,7 @@ func isInternalLoadBalancer(lb *network.LoadBalancer) bool {
 }
 
 // getBackendPoolName the LB BackendPool name for a service.
-// to ensure backword and forward compat:
+// to ensure backward and forward compat:
 // SingleStack -v4 (pre v1.16) => BackendPool name == clusterName
 // SingleStack -v6 => BackendPool name == <clusterName>-IPv6 (all cluster bootstrap uses this name)
 // DualStack
@@ -327,12 +327,59 @@ func (az *Cloud) serviceOwnsRule(service *v1.Service, rule string) bool {
 	return strings.HasPrefix(strings.ToUpper(rule), strings.ToUpper(prefix))
 }
 
-func (az *Cloud) serviceOwnsFrontendIP(fip network.FrontendIPConfiguration, service *v1.Service) bool {
+// There are two cases when a service owns the frontend IP config:
+// 1. The primary service, which means the frontend IP config is created after the creation of the service.
+// This means the name of the config can be tracked by the service UID.
+// 2. The secondary services must have their loadBalancer IP set if they want to share the same config as the primary
+// service. Hence, it can be tracked by the loadBalancer IP.
+func (az *Cloud) serviceOwnsFrontendIP(fip network.FrontendIPConfiguration, service *v1.Service) (bool, bool, error) {
+	var isPrimaryService bool
 	baseName := az.GetLoadBalancerName(context.TODO(), "", service)
-	return strings.HasPrefix(*fip.Name, baseName)
+	if strings.HasPrefix(to.String(fip.Name), baseName) {
+		klog.V(6).Infof("serviceOwnsFrontendIP: found primary service %s of the "+
+			"frontend IP config %s", service.Name, *fip.Name)
+		isPrimaryService = true
+		return true, isPrimaryService, nil
+	}
+
+	loadBalancerIP := service.Spec.LoadBalancerIP
+	if loadBalancerIP == "" {
+		// it is a must that the secondary services set the loadBalancer IP
+		return false, isPrimaryService, nil
+	}
+
+	// for external secondary service the public IP address should be checked
+	if !requiresInternalLoadBalancer(service) {
+		pipResourceGroup := az.getPublicIPAddressResourceGroup(service)
+		pip, err := az.findMatchedPIPByLoadBalancerIP(service, loadBalancerIP, pipResourceGroup)
+		if err != nil {
+			klog.Errorf("serviceOwnsFrontendIP: unexpected error when finding match public IP of the service %s with loadBalancerLP %s", service.Name, loadBalancerIP)
+			return false, isPrimaryService, nil
+		}
+
+		if pip != nil && pip.ID != nil && pip.PublicIPAddressPropertiesFormat != nil && pip.IPAddress != nil {
+			if strings.EqualFold(*pip.ID, *fip.PublicIPAddress.ID) {
+				klog.V(4).Infof("serviceOwnsFrontendIP: found secondary service %s of the frontend IP config %s", service.Name, *fip.Name)
+
+				return true, isPrimaryService, nil
+			}
+			klog.V(4).Infof("serviceOwnsFrontendIP: the public IP with ID %s is being referenced by other service with public IP address %s", *pip.ID, *pip.IPAddress)
+
+			return false, isPrimaryService, nil
+		}
+
+		return false, isPrimaryService, fmt.Errorf("serviceOwnsFrontendIP: wrong parameters")
+	}
+
+	// for internal secondary service the private IP address on the frontend IP config should be checked
+	if fip.PrivateIPAddress == nil {
+		return false, isPrimaryService, nil
+	}
+
+	return strings.EqualFold(*fip.PrivateIPAddress, loadBalancerIP), isPrimaryService, nil
 }
 
-func (az *Cloud) getFrontendIPConfigName(service *v1.Service) string {
+func (az *Cloud) getDefaultFrontendIPConfigName(service *v1.Service) string {
 	baseName := az.GetLoadBalancerName(context.TODO(), "", service)
 	subnetName := subnet(service)
 	if subnetName != nil {

staging/src/k8s.io/legacy-cloud-providers/azure/azure_standard_test.go

@@ -35,6 +35,7 @@ import (
 	"k8s.io/apimachinery/pkg/types"
 	cloudprovider "k8s.io/cloud-provider"
 	"k8s.io/legacy-cloud-providers/azure/clients/interfaceclient/mockinterfaceclient"
+	"k8s.io/legacy-cloud-providers/azure/clients/publicipclient/mockpublicipclient"
 	"k8s.io/legacy-cloud-providers/azure/clients/vmclient/mockvmclient"
 	"k8s.io/legacy-cloud-providers/azure/retry"
 )
@@ -447,7 +448,7 @@ func TestGetFrontendIPConfigName(t *testing.T) {
 		svc.Annotations[ServiceAnnotationLoadBalancerInternalSubnet] = c.subnetName
 		svc.Annotations[ServiceAnnotationLoadBalancerInternal] = strconv.FormatBool(c.isInternal)
 
-		ipconfigName := az.getFrontendIPConfigName(svc)
+		ipconfigName := az.getDefaultFrontendIPConfigName(svc)
 		assert.Equal(t, c.expected, ipconfigName, c.description)
 	}
 }
@@ -1509,3 +1510,158 @@ func TestStandardEnsureHostsInPool(t *testing.T) {
 		}
 	}
 }
+
+func TestServiceOwnsFrontendIP(t *testing.T) {
+	ctrl := gomock.NewController(t)
+	defer ctrl.Finish()
+	cloud := GetTestCloud(ctrl)
+
+	testCases := []struct {
+		desc         string
+		existingPIPs []network.PublicIPAddress
+		fip          network.FrontendIPConfiguration
+		service      *v1.Service
+		isOwned      bool
+		isPrimary    bool
+		expectedErr  error
+	}{
+		{
+			desc: "serviceOwnsFrontendIP should detect the primary service",
+			fip: network.FrontendIPConfiguration{
+				Name: to.StringPtr("auid"),
+			},
+			service: &v1.Service{
+				ObjectMeta: meta.ObjectMeta{
+					UID: types.UID("uid"),
+				},
+			},
+			isOwned:   true,
+			isPrimary: true,
+		},
+		{
+			desc: "serviceOwnsFrontendIP should return false if the secondary external service doesn't set it's loadBalancer IP",
+			fip: network.FrontendIPConfiguration{
+				Name: to.StringPtr("auid"),
+			},
+			service: &v1.Service{
+				ObjectMeta: meta.ObjectMeta{
+					UID: types.UID("secondary"),
+				},
+			},
+		},
+		{
+			desc: "serviceOwnsFrontendIP should report a not found error if there is no public IP " +
+				"found according to the external service's loadBalancer IP but do not return the error",
+			existingPIPs: []network.PublicIPAddress{
+				{
+					ID: to.StringPtr("pip"),
+					PublicIPAddressPropertiesFormat: &network.PublicIPAddressPropertiesFormat{
+						IPAddress: to.StringPtr("4.3.2.1"),
+					},
+				},
+			},
+			fip: network.FrontendIPConfiguration{
+				Name: to.StringPtr("auid"),
+				FrontendIPConfigurationPropertiesFormat: &network.FrontendIPConfigurationPropertiesFormat{
+					PublicIPAddress: &network.PublicIPAddress{
+						ID: to.StringPtr("pip"),
+					},
+				},
+			},
+			service: &v1.Service{
+				ObjectMeta: meta.ObjectMeta{
+					UID: types.UID("secondary"),
+				},
+				Spec: v1.ServiceSpec{
+					LoadBalancerIP: "1.2.3.4",
+				},
+			},
+		},
+		{
+			desc: "serviceOwnsFrontendIP should return false if there is a mismatch between the PIP's ID and " +
+				"the counterpart on the frontend IP config",
+			existingPIPs: []network.PublicIPAddress{
+				{
+					ID: to.StringPtr("pip"),
+					PublicIPAddressPropertiesFormat: &network.PublicIPAddressPropertiesFormat{
+						IPAddress: to.StringPtr("4.3.2.1"),
+					},
+				},
+			},
+			fip: network.FrontendIPConfiguration{
+				Name: to.StringPtr("auid"),
+				FrontendIPConfigurationPropertiesFormat: &network.FrontendIPConfigurationPropertiesFormat{
+					PublicIPAddress: &network.PublicIPAddress{
+						ID: to.StringPtr("pip1"),
+					},
+				},
+			},
+			service: &v1.Service{
+				ObjectMeta: meta.ObjectMeta{
+					UID: types.UID("secondary"),
+				},
+				Spec: v1.ServiceSpec{
+					LoadBalancerIP: "4.3.2.1",
+				},
+			},
+		},
+		{
+			desc: "serviceOwnsFrontendIP should detect the secondary external service",
+			existingPIPs: []network.PublicIPAddress{
+				{
+					ID: to.StringPtr("pip"),
+					PublicIPAddressPropertiesFormat: &network.PublicIPAddressPropertiesFormat{
+						IPAddress: to.StringPtr("4.3.2.1"),
+					},
+				},
+			},
+			fip: network.FrontendIPConfiguration{
+				Name: to.StringPtr("auid"),
+				FrontendIPConfigurationPropertiesFormat: &network.FrontendIPConfigurationPropertiesFormat{
+					PublicIPAddress: &network.PublicIPAddress{
+						ID: to.StringPtr("pip"),
+					},
+				},
+			},
+			service: &v1.Service{
+				ObjectMeta: meta.ObjectMeta{
+					UID: types.UID("secondary"),
+				},
+				Spec: v1.ServiceSpec{
+					LoadBalancerIP: "4.3.2.1",
+				},
+			},
+			isOwned: true,
+		},
+		{
+			desc: "serviceOwnsFrontendIP should detect the secondary internal service",
+			fip: network.FrontendIPConfiguration{
+				Name: to.StringPtr("auid"),
+				FrontendIPConfigurationPropertiesFormat: &network.FrontendIPConfigurationPropertiesFormat{
+					PrivateIPAddress: to.StringPtr("4.3.2.1"),
+				},
+			},
+			service: &v1.Service{
+				ObjectMeta: meta.ObjectMeta{
+					UID:         types.UID("secondary"),
+					Annotations: map[string]string{ServiceAnnotationLoadBalancerInternal: "true"},
+				},
+				Spec: v1.ServiceSpec{
+					LoadBalancerIP: "4.3.2.1",
+				},
+			},
+			isOwned: true,
+		},
+	}
+
+	for _, test := range testCases {
+		mockPIPClient := mockpublicipclient.NewMockInterface(ctrl)
+		cloud.PublicIPAddressesClient = mockPIPClient
+		mockPIPClient.EXPECT().List(gomock.Any(), gomock.Any()).Return(test.existingPIPs, nil).MaxTimes(1)
+
+		isOwned, isPrimary, err := cloud.serviceOwnsFrontendIP(test.fip, test.service)
+		assert.Equal(t, test.expectedErr, err, test.desc)
+		assert.Equal(t, test.isOwned, isOwned, test.desc)
+		assert.Equal(t, test.isPrimary, isPrimary, test.desc)
+	}
+}

staging/src/k8s.io/legacy-cloud-providers/azure/azure_test.go

@@ -231,6 +231,7 @@ func setMockLBs(az *Cloud, ctrl *gomock.Controller, expectedLBs *[]network.LoadB
 		fips := []network.FrontendIPConfiguration{
 			{
 				Name: to.StringPtr(fmt.Sprintf("a%s%d", fullServiceName, serviceIndex)),
+				ID:   to.StringPtr("fip"),
 				FrontendIPConfigurationPropertiesFormat: &network.FrontendIPConfigurationPropertiesFormat{
 					PrivateIPAllocationMethod: "Dynamic",
 					PublicIPAddress:           &network.PublicIPAddress{ID: to.StringPtr(fmt.Sprintf("testCluster-a%s%d", fullServiceName, serviceIndex))},
@@ -249,6 +250,7 @@ func setMockLBs(az *Cloud, ctrl *gomock.Controller, expectedLBs *[]network.LoadB
 		})
 		fip := network.FrontendIPConfiguration{
 			Name: to.StringPtr(fmt.Sprintf("a%s%d", fullServiceName, serviceIndex)),
+			ID:   to.StringPtr("fip"),
 			FrontendIPConfigurationPropertiesFormat: &network.FrontendIPConfigurationPropertiesFormat{
 				PrivateIPAllocationMethod: "Dynamic",
 				PublicIPAddress:           &network.PublicIPAddress{ID: to.StringPtr(fmt.Sprintf("testCluster-a%s%d", fullServiceName, serviceIndex))},
@@ -292,10 +294,10 @@ func testLoadBalancerServiceDefaultModeSelection(t *testing.T, isInternal bool)
 		svcName := fmt.Sprintf("service-%d", index)
 		var svc v1.Service
 		if isInternal {
-			svc = getInternalTestService(svcName, 8081)
+			svc = getInternalTestService(svcName, int32(index))
 			validateTestSubnet(t, az, &svc)
 		} else {
-			svc = getTestService(svcName, v1.ProtocolTCP, nil, false, 8081)
+			svc = getTestService(svcName, v1.ProtocolTCP, nil, false, int32(index))
 		}
 
 		expectedLBName := setMockLBs(az, ctrl, &expectedLBs, "service", 1, index, isInternal)
@@ -349,10 +351,10 @@ func testLoadBalancerServiceAutoModeSelection(t *testing.T, isInternal bool) {
 		svcName := fmt.Sprintf("service-%d", index)
 		var svc v1.Service
 		if isInternal {
-			svc = getInternalTestService(svcName, 8081)
+			svc = getInternalTestService(svcName, int32(index))
 			validateTestSubnet(t, az, &svc)
 		} else {
-			svc = getTestService(svcName, v1.ProtocolTCP, nil, false, 8081)
+			svc = getTestService(svcName, v1.ProtocolTCP, nil, false, int32(index))
 		}
 		setLoadBalancerAutoModeAnnotation(&svc)
 
@@ -421,10 +423,10 @@ func testLoadBalancerServicesSpecifiedSelection(t *testing.T, isInternal bool) {
 		svcName := fmt.Sprintf("service-%d", index)
 		var svc v1.Service
 		if isInternal {
-			svc = getInternalTestService(svcName, 8081)
+			svc = getInternalTestService(svcName, int32(index))
 			validateTestSubnet(t, az, &svc)
 		} else {
-			svc = getTestService(svcName, v1.ProtocolTCP, nil, false, 8081)
+			svc = getTestService(svcName, v1.ProtocolTCP, nil, false, int32(index))
 		}
 		lbMode := fmt.Sprintf("%s,%s", selectedAvailabilitySetName1, selectedAvailabilitySetName2)
 		setLoadBalancerModeAnnotation(&svc, lbMode)
@@ -470,10 +472,10 @@ func testLoadBalancerMaxRulesServices(t *testing.T, isInternal bool) {
 		svcName := fmt.Sprintf("service-%d", index)
 		var svc v1.Service
 		if isInternal {
-			svc = getInternalTestService(svcName, 8081)
+			svc = getInternalTestService(svcName, int32(index))
 			validateTestSubnet(t, az, &svc)
 		} else {
-			svc = getTestService(svcName, v1.ProtocolTCP, nil, false, 8081)
+			svc = getTestService(svcName, v1.ProtocolTCP, nil, false, int32(index))
 		}
 
 		setMockLBs(az, ctrl, &expectedLBs, "service", az.Config.MaximumLoadBalancerRuleCount, index, isInternal)
@@ -551,10 +553,10 @@ func testLoadBalancerServiceAutoModeDeleteSelection(t *testing.T, isInternal boo
 		svcName := fmt.Sprintf("service-%d", index)
 		var svc v1.Service
 		if isInternal {
-			svc = getInternalTestService(svcName, 8081)
+			svc = getInternalTestService(svcName, int32(index))
 			validateTestSubnet(t, az, &svc)
 		} else {
-			svc = getTestService(svcName, v1.ProtocolTCP, nil, false, 8081)
+			svc = getTestService(svcName, v1.ProtocolTCP, nil, false, int32(index))
 		}
 		setLoadBalancerAutoModeAnnotation(&svc)
 
@@ -573,10 +575,10 @@ func testLoadBalancerServiceAutoModeDeleteSelection(t *testing.T, isInternal boo
 		svcName := fmt.Sprintf("service-%d", index)
 		var svc v1.Service
 		if isInternal {
-			svc = getInternalTestService(svcName, 8081)
+			svc = getInternalTestService(svcName, int32(index))
 			validateTestSubnet(t, az, &svc)
 		} else {
-			svc = getTestService(svcName, v1.ProtocolTCP, nil, false, 8081)
+			svc = getTestService(svcName, v1.ProtocolTCP, nil, false, int32(index))
 		}
 
 		setLoadBalancerAutoModeAnnotation(&svc)
@@ -919,7 +921,7 @@ func TestReconcileLoadBalancerMultipleServices(t *testing.T) {
 	setMockEnv(az, ctrl, expectedInterfaces, expectedVirtualMachines, 2)
 
 	svc1 := getTestService("service1", v1.ProtocolTCP, nil, false, 80, 443)
-	svc2 := getTestService("service2", v1.ProtocolTCP, nil, false, 80)
+	svc2 := getTestService("service2", v1.ProtocolTCP, nil, false, 81)
 
 	expectedLBs := make([]network.LoadBalancer, 0)
 	setMockLBs(az, ctrl, &expectedLBs, "service", 1, 1, false)
@@ -1030,7 +1032,7 @@ func TestServiceRespectsNoSessionAffinity(t *testing.T) {
 	mockPIPsClient := mockpublicipclient.NewMockInterface(ctrl)
 	az.PublicIPAddressesClient = mockPIPsClient
 	mockPIPsClient.EXPECT().CreateOrUpdate(gomock.Any(), gomock.Any(), gomock.Any(), gomock.Any()).Return(nil).AnyTimes()
-	mockPIPsClient.EXPECT().Get(gomock.Any(), az.ResourceGroup, "testCluster-aservicesanone", gomock.Any()).Return(expectedPIP, nil).AnyTimes()
+	mockPIPsClient.EXPECT().Get(gomock.Any(), az.ResourceGroup, gomock.Any(), gomock.Any()).Return(expectedPIP, nil).AnyTimes()
 
 	lb, err := az.reconcileLoadBalancer(testClusterName, &svc, clusterResources.nodes, true /* wantLb */)
 	if err != nil {
@@ -1082,7 +1084,7 @@ func TestServiceRespectsClientIPSessionAffinity(t *testing.T) {
 	mockPIPsClient := mockpublicipclient.NewMockInterface(ctrl)
 	az.PublicIPAddressesClient = mockPIPsClient
 	mockPIPsClient.EXPECT().CreateOrUpdate(gomock.Any(), gomock.Any(), gomock.Any(), gomock.Any()).Return(nil).AnyTimes()
-	mockPIPsClient.EXPECT().Get(gomock.Any(), az.ResourceGroup, "testCluster-aservicesaclientip", gomock.Any()).Return(expectedPIP, nil).AnyTimes()
+	mockPIPsClient.EXPECT().Get(gomock.Any(), az.ResourceGroup, gomock.Any(), gomock.Any()).Return(expectedPIP, nil).AnyTimes()
 
 	lb, err := az.reconcileLoadBalancer(testClusterName, &svc, clusterResources.nodes, true /* wantLb */)
 	if err != nil {
@@ -1600,7 +1602,7 @@ func validateLoadBalancer(t *testing.T, loadBalancer *network.LoadBalancer, serv
 				}
 			}
 			expectedFrontendIP := ExpectedFrontendIPInfo{
-				Name:   az.getFrontendIPConfigName(&svc),
+				Name:   az.getDefaultFrontendIPConfigName(&svc),
 				Subnet: to.StringPtr(expectedSubnetName),
 			}
 			expectedFrontendIPs = append(expectedFrontendIPs, expectedFrontendIP)