Alerted by Storage Mojo I found a fascinating research paper from HP. Let me quote the first sentence in the summary: "A Federated Array of Bricks (FAB) is a logical disk system that provides the reliability and performance of enterprise-class disk arrays, at a fraction of the cost and with better scalability."

That sounds appetising. It goes on to say: "The unit of deployment in FAB is a brick, a small rack-mounted storage appliance built from commodity components including disks, a CPU, NVRAM, and network cards. Bricks federate themselves in a completely decentralized manner to provide users with a set of logical volumes."

I wonder if a brick in a FAB is similar to a tray in Sun's StorageTek 5800 Honeycomb product?

The HP researchers point out that the key requirement separating "enterprise-class disk arrays from consumer-class storage systems is their absolute reliability: a disk array must never lose data or stop serving data, under any circumstances short of complete disaster." So how can you build this reliability into a FAB? It's comes from using smart JBODs, if that is not a contradiction in terms.

Each bunch of disks has an embedded server. Software on these servers is used to achieve the following: "FAB provides (enterprise-class) reliability ... through replication: we store the same disk block on multiple bricks, and we create redundant paths between all components of the system. FAB performance scales by completely distributing all functionality (no centralized bottlenecks) across the set of available bricks."

The potential scalability is impressive: "A single FAB system is anticipated to contain up to 5000 bricks with a logical capacity of 2 petabytes."

Whether this work will ever result in real products is an interesting question. Read the research paper by downloading it from here.