It depends on what they want to do with the NAS; what their server and storage environment looks like; what applications...
will be using the NAS; what performance and capacity will be required; and how many servers will be accessing the NAS. It depends on their DR, business continuity and compliance requirements; whether the NAS is centralized or distributed; growth and growth strategies; and whether the NAS is an integrated system or a NAS head attached to a SAN. It also depends on organizational management strategy, skills and personnel; what level of service is required upfront, upon implementation and ongoing. And it depends on the incumbent storage vendor and satisfaction with that vendor; the vendor limitation policies of the organization; and which vendors have organization "favor" and which ones don't.
In summary, it depends, it depends and it depends. Mostly, it depends on common sense. Unfortunately, as Voltaire once said, "common sense is not so common." The answer will inevitably vary among end users. So, instead of recommending a vendor or product, I am suggesting a common sense process:
- NAS head using pooled SAN assets
- NAS system supplying its own block-storage capacity
- NAS and SAN combination for different applications
- Feature function, beyond what is required for the life of the storage, must (I repeat MUST) have a quantifiable value proposition to the organization. This means the benefits outweigh the costs. Always specify the results and NOT the method in achieving those results. This will force vendors to be creative in meeting your needs.
Identify all service requirements for implementation and support. Make sure all costs are unmistakably identified in all vendors' proposals. Don't get hung up on the latest greatest technology trends such as global name space, clustering, WAFS or file virtualization. All technology is a means to accomplish an end. All that matters is that your needs are met within your technology, budget and political restraints. And, that your tactical and strategic requirements are met. If the technology doesn't meet those requirements, then it is worthless to you.
Although this is a common sense approach, it also requires plain old-fashioned planning. The alternative is just putting your fate in the hands of your favorite trusted vendor. If you choose this path, remember the immortal words of former president Ronald Reagan, "trust, but verify."