Friday, July 24, 2009

You Get What You Pay For - Promise Technology RAID Arrays

TJHSST's Computer Systems Lab has a student systems administrators program, of which I was a participant during my time there. The "sysadmins" run production systems that support core school services such as student e-mail, the student Intranet, and the main website. The program is very fortunate to be able to use a part of the school's IT budget to purchase equipment to support these services; there was once a day and age when this was not so and the hardware ran ancient. So of course, in trying to be good stewards of the privilege, we try to find good deals on hardware that we are after. But in some cases, we learn the hard way that cheap hardware is cheap for a reason.

Enter the Promise VTrak M310i storage array.

On paper, this product looks great. It's cheap and comes with hard disk carriers so you can buy your own hard disks instead of being tied down to overpriced OEM disks. It supports everything that we want it to do. But at the end of the day, the on-board disk controller is unreliable. Maybe that's because we are using it with Solaris systems. Maybe it's because we're trying to use it more as a JBOD than a RAID. Neither of those are legitimate reasons, though, since the product advertises support for iSCSI, and allows you to create a JBOD configuration. If you claim to support an industry standard protocol or claim to be able to do something, there is no such thing as "it should work with this OS but not that one," or "we support this but not the very specific way you're doing it." There is a reason some things are called standards. Whatever the reasons, though, we are now stuck with a product that fails erratically; sometimes only a few days pass between failures, and sometimes a couple of weeks do. What we'd like now is a JBOD (no RAID controller to fail) that we can just put these disks in. However, to buy a good product from a Tier 1 vendor means that you can't just put your own disks in, and we aren't in a hurry to part with the disks that we already bought. Or at least with Sun's J4200 JBOD array, the product is new enough that it's hard or expensive to get the needed parts from the aftermarket. We've tried complaining to Promise and asking to get our units exchanged for their JBOD models, in hopes that they would work better since our units are still covered under warranty, but last I heard was that we'd gotten nowhere in trying to do that.

On a related note, we recently attempted setting up a donated Promise SuperTrak RM8000 RAID array. It has a decent amount of storage, but we were disgusted after spending 5 minutes trying to configure it. Apparently the product lets you accidentally create an invalid configuration using its non-intuitive interface, then has no way for you to delete it. It's possible there is a reset-all button hidden somewhere on the device, but we haven't had time to look for it.

So while Promise seems to have been slowly improving their products over time, I cannot deem their budget products production-worthy. It's possible their more expensive enterprise-class products work okay, but I can't speak to those. And before you say "upgrade the firmware", the product should at least work before it even ships. Blatant bugs like these show what seems to be either poor engineering or a lack of sufficient testing. And to be fair to the engineers, it could as well be a failure of management. A BlueArc storage product I've worked with had some issues that, after conversing with some of their engineers, turned out was a result of having the product rushed to market.

What is our solution? We don't really have one yet. We'll either wait until aftermarket parts are both available and affordable, or we'll just have to fork over additional money to buy a fully integrated and tested product. So much for trying to save some money. What I do know is we won't be buying a Promise product again anytime soon.

Keywords: Promise VTrak, storage array, review, SAN

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