Is there a way I can start HDFS (the namenode) from a Java main and run unit tests against that? I need to integrate my Java/HDFS program into unit tests, and the unit test machine might not have Hadoop installed. I’m currently running the unit tests by hand with hadoop jar ... My unit tests create a bunch of (small) files in HDFS and manipulate them. I use the fs API for that. I don’t have map/reduce jobs (yet!).