One alternative to buying expensive storage-area networks or other hardware-based dedicated storage is to deploy open source storage software on existing server hardware. For this test, we evaluated three such open source storage products, GlusterFS 3.3, Ceph 0.72 and Apache Hadoop 2.2.0.
All three did a good job, but as you might expect, there is a tradeoff when it comes to using open source storage. This is a DIY project: the documentation might not be as comprehensive as you might like, installation can be tricky, GUI-based management tools might not be available and if anything goes wrong, you’re pretty much on your own.