I will begin by stating that I do not believe this is a duplicate of Why is business-class storage so expensive?.
My question is specifically about SAS drive enclosures, and justifying their expense.
Examples of the types of enclosures I'm referring to are:
Each of the above is a 2U direct attached external SAS drive enclosure, with space for around 24 X 2.5" drives.
I'm talking about the bare enclosure, not the drives. I am aware of the difference between enterprise class hard drives and consumer class.
As an example of "ball-park" prices, the HP D2700 (25 X 2.5" drives) is currently around $1750 without any drives (checked Dec 2012 on Amazon US). A low end HP DL360 server is around $2000, and that contains CPU, RAM, motherboard, SAS RAID controller, networking, and slots for 8 X 2.5" drives.
When presenting clients or management with a breakdown of costs for a proposed server with storage, it seems odd that the enclosure is a significant item, given that it is essentially passive (unless I am mistaken).
My questions are:
Have I misunderstood the components of a SAS drive enclosure? Isn't it just a passive enclosure with a power supply, SAS cabling, and space for lots of drives?
Why is the cost seemingly so expensive, especially when compared to a server. Given all the components that an enclosure does not have (motherboard, CPU, RAM, networking, video) I would expect an enclosure to be significantly less expensive.
Currently our strategy when making server recommendations to our clients is to avoid recommending an external drive enclosure because of the price of the enclosures. However, assuming one cannot physically fit enough drives into the base server, and the client does not have a SAN or NAS available, then an enclosure is a sensible option. It would be nice to be able to explain to the client why the enclosure costs as much as it does.