Azure Web Sites – block web access to non-production deployment slots
Windows Azure Web Sites supports Staged Publishing functionality, which allows you to create a staging site slot where you can publish a new version of the website and then test it before swapping to the production environment. By default the non-production deployment slot has its own hostname that you use to test the bits deployed there. Sometimes, however you may want to prevent users from browsing to your non-production deployment slot while you are testing it.