Thanks for your very well presented comments.  I might have guessed you worked for Hitachi with such a well thought and considered response – a world away from the childish mud flinging and name calling we get from some vendors.

Thanks again for your input.

Nigel

To decide between internal SATA within a monolithic storage frame or a modular storage in a virtualized environment aka  Frankenstorage as Chuck calls it, is an interesting one. From my perspective, both could be right answers or the wrong answer depending upon what a customer is trying to accomplish within a constrained capital environment. After all if we had infinite capital inflows we would put all our applications on Tier 1 storage. For the record I work at Hitachi.
 
Internal SATA within a monolithic architecture has its place. After all there is a cost of entry for getting into the virtualization game. Agreed, from a $/TB perspective the external storage is always cheaper than the internal slot. However, if the customer is looking for a small percentage of his apps on lower tier then internal SATA works well. Also if that is the only storage frame the customer has on his floor there is an argument to be made that it is easier to manage. However few large customers have just one frame.

As the percentage of applications on lower tier goes on increasing there is a break even point from an economics perspective where virtualized modular storage becomes more and more attractive. Finally customers must also consider the cost of software. Most often software is cheaper for external tiers of storage than inside the box. Though there are vendors who give a price break for internal SATA.
 
After all economics play a big role in buying behavior especially in a downturn.

Use cases of Frankenstorage 

Besides the above economic argument there are other scenarios where internal SATA is not even a consideration. We see customers using virtualization for extending the life of existing assets.  Especially in this economy customers are looking to increase their return on invested assets (ROA) and extending the life of a depreciated asset behind an intelligent virtualization controller is one way to do it. Another use case is around data migration which is prone to both human and IT risks and virtualization is a big enabler for seamless technology refreshes.

-Vijay Ramaswamy