fix managed cluster diff so aks added fields are omitted

azure/services/managedclusters/managedclusters.go

@@ -259,6 +259,12 @@ func (s *Service) Reconcile(ctx context.Context) error {
 			Name: containerservice.ManagedClusterSKUNameBasic,
 			Tier: tierName,
 		}
+	} else {
+		// Add the default sku so that the diff will match if no sku is specified by the spec.
+		managedCluster.Sku = &containerservice.ManagedClusterSKU{
+			Name: containerservice.ManagedClusterSKUNameBasic,
+			Tier: containerservice.ManagedClusterSKUTierFree,
+		}
 	}
 
 	if managedClusterSpec.LoadBalancerProfile != nil {
@@ -303,6 +309,16 @@ func (s *Service) Reconcile(ctx context.Context) error {
 			return errors.New(msg)
 		}
 
+		// Normalize the LoadBalancerProfile so the diff below doesn't get thrown off by AKS added properties.
+		if managedCluster.NetworkProfile.LoadBalancerProfile == nil {
+			// If our LoadBalancerProfile generated by the spec is nil, then don't worry about what AKS has added.
+			existingMC.NetworkProfile.LoadBalancerProfile = nil
+		} else {
+			// If our LoadBalancerProfile generated by the spec is not nil, then remove the effective outbound IPs from
+			// AKS.
+			existingMC.NetworkProfile.LoadBalancerProfile.EffectiveOutboundIPs = nil
+		}
+
 		diff := computeDiffOfNormalizedClusters(managedCluster, existingMC)
 		if diff != "" {
 			klog.V(2).Infof("Update required (+new -old):\n%s", diff)