Software Defined Storage: Does the model still work?

I recently stumbled on an article from last year, VAST Data, an SSD-focused single tier universal storage company made the announcement that they would be shifting their business to a software-based subscription model (i.e. software-defined). Having developed software-defined solutions, I personally have mixed feelings about this decision, the majority of which are negative.

VAST Data, the high performance storage startup, is to stop selling its own hardware. It will concentrate instead on selling software on a subscription basis, and will certify hardware appliances built by Avnet.

It is part of the Gemini subscription program the company launched back in January.

“Instead of purchasing hardware and software together and being caught up in an endless refresh cycle as we’ve seen for the past 30 years, Gemini offers the freedom, flexibility, and simplicity, all at an affordable cost, that organisations need to deploy an infinite storage lifecycle,” Renen Hallak, VAST Data founder and CEO, said today in a press statement.

What does that mean though? What is Software Defined Storage (often abbreviated to SDS)? At a high level: It is independent software used to manage storage hardware, regardless of the type or hardware vendor. The idea is a simple one. Most off-the-shelf hardware has been somewhat commoditized. That is, take your HP’s, your Dell’s, Supermicro’s or anything else. Fill it with whatever Seagate, Western Digital, HGST, and / or other storage drive. Then let the software do its magic. Under this model, it is the software that has become the defining factor.

It is an attractive approach to managing your data. Think about it: no hardware vendor lock-in. Instead of being an EMC shop or a NetApp shop, you are now given the option to mix and match hardware while relying on the software to bring it all together.

Although, there is a downside to all of this. Let us ignore the obvious fact that it is up to you to locate and purchase the hardware separate from the software. Software Defined Storage promises us the world but only in recent years has started to showcase its shortcoming: that being centered around the hardware.

More often than not, the majority of unplanned systems downtime are the result of hardware failure, data loss, local disasters or failed data recovery. The software can only do so much to prevent or work around such failures. Who then is responsible for monitoring, maintaining, replacing the hardware? The answer: the customer. That includes checking hardware logs on a routine basis and updating device firmware. Most software defined solutions are not built with the facilities or capabilities to perform such tasks. Nor do they have the legal rights to redistribute vendor utilities to adopt the feature(s).

Once upon a time, I worked for a storage startup. We built our own Linux distribution, customized with both open source and secret-sauce applications. We promised that it would install and function on general commodity hardware. The problem was: not all hardware was the same and we found ourselves customizing our platform to cater to the deficiencies experienced on said hardware. All in the name of customer experience. When disaster occurred, the customer looked to [or pointed the finger at] us regardless of who purchased that hardware. And in many cases, we had to hold their hand to ensure that their equipment was up-to-date with the latest and greatest hardware code.

This is the complete opposite experience with non-software-defined products. You may get less flexibility in the data center but the customer receives something from the vendor that is almost guaranteed to be thoroughly tested and supported.

What has your experience been? Does the software-defined anything still work?