code: func (az *Cloud) getAzureLoadBalancerName(clusterName string, vmSetName string, isInternal bool) string {
  	lbNamePrefix := vmSetName
  	if strings.EqualFold(vmSetName, az.vmSet.GetPrimaryVMSetName()) || az.useStandardLoadBalancer() {
  		lbNamePrefix = clusterName
  	}
  	if isInternal {
  		return fmt.Sprintf("%s%s", lbNamePrefix, InternalLoadBalancerNameSuffix)
  	}
  	return lbNamePrefix
  }
docs: // For a load balancer, all frontend ip should reference either a subnet or publicIpAddress.
  // Thus Azure do not allow mixed type (public and internal) load balancer.
  // So we'd have a separate name for internal load balancer.
  // This would be the name for Azure LoadBalancer resource.