How to find the end user's IP address in a cloud environment

We noticed today that one of our ASP.NET cloud applications incorrectly identified the end user's IP address. Our Request.ServerVariables["REMOTE_HOST"] and Request.ServerVariables["REMOTE_ADDR"] were initialized with the load balancer information instead of the end user's data.

We found the end user's IP in a different place: Request.Headers["X-Cluster-client-IP"].

Happy coding!