Created 10-16-2013 11:12 AM
You could try using HttpFS, it acts as a trusted edge node between the cluster and external clients. It's basically a proxy for WebHDFS, so clients can't talk directly to the namenode / datanodes. This is lower performance, but it should be okay for 10-20GB of data.
See:
http://archive.cloudera.com/cdh4/cdh/4/hadoop/hadoop-hdfs-httpfs/