A major objective for most organizations either right now or in the near future is to put in place a private storage cloud architecture to make the storage and ongoing management of their data easier to accomplish. It is for these reasons that many organizations are turning to scale-out storage systems as the preferred architecture to achieve this objective. Here is where it gets tricky. Scale-out storage system architectures have diverged to offer organizations many paths to follow in order to arrive at their desired private storage cloud destination.
Both scale-out storage systems and private storage clouds are still relatively new concepts in the broader storage technology space. The forerunners of today’s modern scale-out storage systems, they first started to appear about a decade ago with the term “private storage clouds” emerging about five (5) years ago. However it is only in the last few years that scale-out storage systems have found their way into corporate data centers with the phrase “private storage clouds” becoming part of the corporate IT lexicon.
The big appeal of scale-out storage systems was their flexibility to independently add more capacity or performance while still remaining one logical storage system from a management perspective. Further, organizations could start small only deploying as much capacity or performance as they initially needed and then add more of exactly what they needed when they needed it according to their application/business demands.
This flexibility that these systems offer has become even more important in recent years. As companies attempt to meet Big Data growth and longer data retention requirements, scale-out storage systems are emerging as the preferred solution to deliver on them. They may start with a configuration as small as a few dozen terabytes with this flexibility to grow into the hundreds of terabytes or even petabytes. This flexibility comes with minimal or no increases in management overhead and incremental but predictable increases in cost.
This approach explains why these systems have come to more recently be associated with “private storage cloud” terminology. They most closely reflect what organizations expect private storage clouds to look like.
Granted, there are some purists who say that private storage clouds should have no upfront costs and companies should only pay for what they actually use. That day may eventually come. Until then today’s scale-out storage systems define private storage clouds.
Which brings us to an interesting point in time in the evolution of these systems. The first scale-out storage systems were generally based on cluster file system software residing on independent nodes that offer performance (CPU and memory) on one node, storage capacity on a second node or both performance and storage capacity on a single node. This architecture may be found on products such as EMC Isilon, HP StoreAll Storage 9000 and IBM SONAS.
The issue with these products is that while their flexibility and scalability met the needs of large enterprises, small and midsized organizations were unable to afford them. Further, even large enterprises needed the flexibility and scalability features that these scale-out storage systems offered minus their cost for more cost-sensitive applications such as archiving, backup, client virtualization and video surveillance.
This is why in recent years we have seen a number of new providers emerge that provide alternative scale-out architectures that lower the upfront cost while still providing performance that is as good if not even better than these existing solutions.
Two notable entries in this space are Coraid and Gridstore. What makes the scale-out storage systems from these two respective providers notable is rather than using their own nodes to deliver the performance, they move processing of data out to the servers that attach to their storage nodes by installing their own drivers on them.
In Gridstore’s case, it refers to its driver as a “virtual controller” that uses its own storage networking protocol to communicate with its storage nodes. Coraid takes a similar though more open approach leveraging the open standard though little used ATA over Ethernet (AoE) protocol to deliver up its scale-out storage solution.
Both of these approaches do create some additional work in terms of organizations needing to install software on each server in order to use their storage solution. However they also remove many of the upfront capital costs out of their scale-out storage solution that these same organizations are concerned about.
They accomplish this by moving the performance costs traditionally associated with scale-out storage solution out to the servers. Since the environments for which these solutions are intended are usually short on cash but are long on server performance and have access to and control over their server nodes, it works out well for them.
It is because of changes like this in scale-out storage system designs as well in how they are perceived that DCIG is making the following changes to the refresh of its 2011 Enterprise Scale-out Storage Buyer’s Guide.
1. Changing the name of this Buyer’s Guide to the Private Storage Cloud Buyer’s Guide.
2. Changing the inclusion criteria to be more inclusive of these alternative scale-out storage system designs.
3. Changing how it scores and weights the features on these products to more accurately reflect how the features in these systems are being delivered.
Scale-out storage systems are an important new storage solution in today’s crowded storage system space – so much so that these solutions are achieving a coveted association with the “private storage cloud” terminology. As this transition occurs, DCIG sees it as a necessity to change how it refers to these systems in its Buyer’s Guide to better capture how they are being deployed in corporate environments as well as better reflect and capture the subtle but important changes that are occurring in the core of these systems.