First, try to find out how many satisfied customers the vendors actually has. A simple way to accomplish this is to time how long it takes for the vendor to respond to you with references. If it takes more than a few days, then that could be a sign that they don't have a large pool of satisfied customers. Also, when you are speaking with the reference, ask them how often they are a reference--an answer of "all the time" might be an indication that this may be their only satisfied customer.
The second piece of information to get is how easy or hard was it for this reference to be satisfied with their purchase? If they had extensive experience with SANs and NAS prior to this selection, they were probably easier to satisfy. This could have come from the current equipment, or because the reference has a lot of background and experience with the technology. Neither is necessarily bad, but just make sure you understand and factor that into your decision-making process. If this is your first SAN or NAS purchase, ask for references that match your situation.
The third piece of information to get is to understand how the install went. The installation is often going to set the tone for how much you trust the system. Most vendors will get you working eventually, but if it takes a Herculean effort you may never fully trust the system enough to move all your data to it. This may be tough to get from a longtime customer; in fact the personnel that were part of the install process may not even be available.
For the install, you are looking for how much time did it take to get the system up and running versus how much time the vendor or customer expected it would take to get the system up and running. Many days of install may be perfectly acceptable as long as it was planned for. What you want to find out is when there was a wide miss in planned versus actual time spent.
Fourth, you want to understand what day-to-day operations look like. See if you can find out the total number of hours per person spent managing the system. What your looking for, of course, is a low number of hours per TB compared to other vendors. Discount statements like "its easy." Everyone will say that--what you want is actual numbers. Also ask daily operational questions like how long does it take them to provision a volume, assign it to a server, and have that server accessing the volume.
The final piece of information is what happened when something went wrong? Something always goes wrong. What you want to understand is the process and response of both the storage system itself and the people assigned to manage that system. Did the vendor have the staffing and experience to work the customer through the problem? Or was the system so simple that the customer was able to solve the problem itself and not even need the vendor?
None of these suggestions should be taken as the sole test of references, and everything has to be measured against other factors. Lack of response could be a case of disorganization, not a bad system. Always use your own judgment. My goal is to move you from having a love fest reference call to one where you actually get nitty gritty details.
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