Azure how to create an internal endpoint that has load ballancing?

How can an internal endpoint for a web role or a worker role have load ballance? If I declare the endpoint in ServiceDefinition.csdef as <InternalEndpoint name="GeneratePDF" protocol="tcp" /> , and then I expose it like:

// define an internal endpoint for inter-role traffic
  RoleInstanceEndpoint internalEndP开发者_如何学运维oint =
      RoleEnvironment.CurrentRoleInstance.InstanceEndpoints["IGeneratePDF"];
  this.serviceHost.AddServiceEndpoint(
     typeof(IGeneratePDF),
     binding,
     String.Format("net.tcp://{0}/GeneratePDF", internalEndPoint.IPEndpoint));

than I get an endpoint that allows me to call each instance I want. But I don't get load ballancing this way, which is what I want.

probably not the ideal solution, but this seems to be one way of doing it...

    int instances = RoleEnvironment.Roles["InstanceName"].Instances.Count;
    Random rand = new Random();
    var endpoint = RoleEnvironment.Roles["InstanceName"].Instances[rand.Next(instances)].InstanceEndpoints["YourEndpointName"].IPEndpoint;

from what i am reading, only working roles (Roles which are marked as ready) are in the Instances list, so you should only get instances which are working...