Sandbox is very convenient for learning. however, because it’s packaged so well, it also hides a lot of implementation details. For a beginner, that’s great so you don’t get bogged down. The next phase of learning though is able to specify and configures different nodes for different Hadoop roles. One needs to learn the issues in managing and tuning Hadoop cluster so we can fully appreciate Ambari.
In fact if you can show us how to do this through Ambari, all the better. I’d love to write up a blog post about that.