http://ceph.com/
What is Ceph? Ceph is a free software storage platform designed to present object, block, and file storage from a single distributed computer cluster. Ceph’s main goals are to be completely distributed without a single point of failure, scalable to the exabyte level, and freely-available. The data is replicated, making it fault tolerant. (ref)
There was an IBM write up here or you can just ready the cached copy. (l-ceph-pdf)
References:
- http://en.wikipedia.org/wiki/Ceph_(storage)