Coraid’s AoE storage approach anyone?

Storage data communication has become too complicated and expensive. So I love it when I see a technology that genuinely reduces complexity-and saves money-without an obvious performance downside. I am sure cash-strapped small and medium enterprises (SMEs) in particular would concur.

Are you familiar with ATA over Ethernet (or AoE for short)? If you’re a Linux user you may well be, as it has been part of the Linux kernel since 2005. But, according to Kevin Brown, CEO of storage SAN provider Coraid, which is betting its shirt on this technology, “AoE is disruptive technology but has been flying below the radar”. Coraid developed AoE in 2004, then made it open source.

So what is it? Some refer to it as a protocol; others, including Coraid, are more ambivalent, preferring to call it a raw Ethernet compute layer-because the data travels over the wires using Ethernet’s own frames (packets). In a sense it is a bare-metal level 2 data transport method.

Coraid has been quietly exploiting AoE within the Linux community for a few years, while also working on some missing “must haves” to make it more robust and reliable, holding back wider takeup. Nor has it even been available for Windows. Coraid’s AoE EtherDrive scale-out storage and SAN solution now has a Windows driver, snapshots and replication cloning capabilities.

With $35m in new VC funding and a new professional team and advisory board, Coraid is raising the company’s and the technology’s profile. For instance, it is now building an EMEA operation through channel partners. Yet, this does not demonstrate a clear potential for storage market disruption.

So let me take a step back. One can install VMware and create a new virtual server in, say, five minutes; but ask a user how long it can take to get all the relevant storage networking in place and aligned with the VMs. If this takes days or weeks-and it often does-that gets in the way of an agile enterprise IT infrastructure. To rub this in, Coraid has made a video demonstrating its AoE storage installation taking 60 seconds. Coraid also estimates 80% cost-savings using its commodity Ethernet scale-out solution versus an FC equivalent-which is potentially big bucks for most FC installations which cost above $100, 000.

Of course, existing FC or iSCSI users may not be about to abandon their investments, including in their expert personnel, and solution vendors will point to question-marks over AoE; yet these are also cash-strapped times for most businesses. So Brown sees Coraid’s potential in new projects through which users can evaluate and prove the technology for themselves.

One such scenario is where FC users move to Ethernet because they see 10Gb Ethernet (10GbE) costing as little as $500 per port. If, when moving, they could include an evaluation of the merits of Coraid’s AoE solution by trying it out on one project. The FC user should find the Coraid commodity hardware working out at around one-fifth of the FC price per TB-and that it also out-performs it, not least because 10GbE enables massively parallel data communications. That alone could impress enough for a business to decide to gradually spread the technology at FC’s expense.

“They [FC users] come from layers of complexity, switch configuring, HBAs and storage controllers, operating system-to one tier for all equipment,” says Brown. So this is nothing like introducing a new technology; rather, if they abandoned FC/FCoE (or iSCSI), it would actually reduce layers. (The argument is a little weaker versus the relatively new iSCSI, but the price differential and performance could still be significant.)

Despite this, I suspect that AoE will be adopted more quickly by SMEs who are less likely to have FC. Storage requirements rise by 60-80% each year-there is a big cost difference between perhaps $2-5K per TB plus multiple skilled administrators and $5-700 with minimal administration for the Coraid solution. A further small benefit for some, because of the way the solution works, is that AoE can be inserted to replace direct-attach storage (DAS) transparently to the user, adding overall flexibility.