Proprietary Gear Seeks Foothold

Maybe you have to be a rocket scientist to see the wisdom of using proprietary Ethernet protocols in enterprise applications.

How else do you explain two groups in NASA independently implementing Coraid EtherDrive devices within seven months when most enterprise customers shun such one-off solutions?

Coraid and Zetera are challenging the conventional wisdom with storage systems based on a proprietary Ethernet protocol built on open software. Zetera uses User Datagram Protocol (UDP) rather than the Transmission Control Protocol (TCP) used by iSCSI. (See Zetera Rewrites iSCSI.)

Coraid uses a protocol called AoE (ATA over Ethernet) instead of TCP. Linux servers see each disk connected to a Coraid device as a local physical drive.

Like iWarp, these are largely untested Ethernet alternatives to using TCP, which requires extra computing resources. (See Ohio Opts for iWarp.)The question is, if these protocols are based on open source, how come nobody else is using them? Either Coraid or Zetera are smarter than the rest, or they're going down a fool's path. And according to lots of people in the storage industry, it's the second option, especially since most iSCSI customers don't find using TCP much of a strain on their systems.

"Just what we need -- vendor lock-in from an open-source product," cracked one storage analyst, when asked about storage wares from Coraid and Zetera.

Eventually, customers will decide. Zetera doesn't sell products directly, but has lined up partnerships with Bell Micro, Netgear, and StorCase. (See Bell Micro to Sell Zetera, Netgear Ships IP SAN, and StorCase Uses Zetera Tech.) Zetera plans to tackle the enterprise eventually, but so far products based on its technology are geared for networked home and SOHO computers. Enterprise uptake very much remains an open question.

Coraid has announced customers, including two at NASA. (See Coraid Scores NASA Deal, NASA Chooses EtherDrive Blades , and Fiberlink Picks Coraid.) This week the Goddard Space Flight Center purchased an EtherDrive Storage appliance that Coraid rolled out in June to back up data for its Solar Dynamics Observatory (SDO) program. In April, NASA purchased EtherDrive Storage Blades for a geological survey project. Unlike the appliance, the EtherDrive blades have built-in controllers. Both support RAID. (See Coraid Intros EtherDrive Appliance.)

Jim Wiedman, system analyst for NASA contractor Adnet Systems, purchased the appliance for Goddard but says he did not confer with the NASA group that bought the blades. Wiedman doesn't see EtherDrive as a replacement for iSCSI. He sees it as a replacement for tape."I want disk-to-disk backup," Wiedman says. "To get data available faster than we get it off tape is a big plus. We can set up RAID with three disks, and do our regular daily backup to that RAID. For offsite storage, I have the fourth disk -- I can pull it out and take it off site."

Wiedman says he doesn't care if the product or the protocol is immature. He can wait for it to grow up. His group is preparing for a 2008 launch of SDO, a satellite that will send back data about the sun's magnetic field. Wiedman will use EtherDrive to store data that controls the spacecraft, such as information about onboard systems and batteries.

"We're still early in our development cycle," he says. "We've tested it and I like it, and I intend to expand eventually."

Goddard purchased a 1U appliance that connects up to four Serial ATA drives with Gigabit Ethernet connections. The appliance, which Coraid started shipping in June, costs $1,995. With SATA drives costing around $350 for 500 Gbytes, a 2-Tbyte configuration is less than $3,500.

"This is very inexpensive," Wiedman says. "With SATA drives, we can buy as many as we want. If we're going to try to do it in a cost-effective way, tape is our only other option. There aren't lot of good disk backup solutions at this price. Even iSCSI would cost a lot more."Wiedman admits using storage built on a new protocol is risky, but says the risk is small because of the price.

"My biggest concern is it's new and there's not a lot of people using it," he says. "We have plenty of time to test it. If ultimately it doesn't work, we can replace it with network storage. We'll have to spend more money, but we're not out everything. We can certainly still use the SATA drives. The investment risk is low."

Still, iSCSI vendors aren't likely to feel threatened by newcomers like Coraid and Zetera. LeftHand Networks started with its own proprietary protocol before iSCSI, and found no acceptance in the enterprise. LeftHand Chief Strategy Officer Tom Major says the biggest problem was lack of support from operating system vendors, and he doesn't think that will change.

"We got beat up pretty good," Major says. "Vendors said, 'We don't know if our operating systems will work with a non-proprietary protocol.' I think these guys will run into the same problems."

OS support isn't much of any issue for Coraid yet; it still runs only on Linux servers. Coraid made sure it had support from one application vendor. Startup Arkeia certified its network backup software on Coraid's EtherDrive appliances. (See Arkeia, Coraid Partner.) NASA's Wiedman says he hasn't yet decided if he'll purchase Arkeia, but used it to evaluate Coraid's drives.Dave Raffo, Senior Editor, Byte and Switch

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