I recently ran across an article by Robin Harris of StorageMojo that took an interesting take on the long term futures of DAS and SAN.
I would recommend that you read the article, but in summation, Mr. Harris looked at the advancement of network interconnects as a key factor in the increasing adoption of DAS. More specifically, that the price and specs of 10gbE have remained stagnant, making the extreme OPEX and CAPEX investments for network upgrades a tough proposition. This becomes even more evident when you look at the CPU and back-plane improvements (PCIe for instance) over the past few years and couple those improvements with the relative ease in upgrading compute and internal bus against replacing an entire Edge/Core network.
This was an interesting angle that I hadn’t considered as we developed and released our DAS focused capabilities in Storage Foundation 6.1.
DAS, as any one that has seen any of my blogs, presentations, or videos over the past few months, is re-emerging in the enterprise data center as an accepted architecture for high performance, highly available, mission critical workloads. When enterprises consider PCIe SSD for caching, a server SAN architecture for increased flexibility for improved CAPEX and OPEX, or a hyper-converged appliance for plug-and-play applications, they are looking at DAS. Whether they know (or want to admit that they know) it or not.
With our Storage Foundation 6.1 release we are using software to help new and existing customers achieve these benefits within a single solution to define the storage management, data protection, and application availability architectures to meet SLAs. Software Defined Storage and Availability in a single package.
For those that are looking to unlock the increased power of the back-plane and performance of PCIe attached SSD, Flexible Shared Storage enables the server SAN architecture with the ability to put faster interconnects, like InfiniBand and RDMA, into the environment for those applications that need increased bandwidth.
Or, if your network is taxed and the cost/performance benefit is not there, as Mr. Harris points out, SmartIO is available for those customers that want to get more life and performance out of the existing network configuration. SmartIO utilizes internal SSD as a cache for “hot” data to serve a majority of read requests from inside the server, keeping those I/O’s from traversing the network.
As the DAS adoption curve continues to climb, more critical applications will look to utilize the performance improvements that come along with it. Maximizing the flexibility, availability, and performance of these architectures will require an intelligent software stack that can work with any hardware, network, and application.