ISCSI Passes Its Midterm

The head of a testing group at the University of New Hampshire recently finished his seventh round of iSCSI interoperability tests and found devices from multiple vendors played together nicely in a no-frills network setting. Industrial-strength features will have to wait, though.

Stephen Schaeffer, iSCSI consortium manager at the UNH-InterOperability Laboratory (UNH-IOL), pronounced iSCSI poised for eventual widespread adoption.” Schaeffer’s group conducts iSCSI tests every six months or so.

“In previous plugfests, we found bugs in the standard itself as well as the vendors’ devices,” Schaeffer says. “This time there was no problem with the standard itself. ISCSI is a mature, ready-to-deploy technology.”

Would he have made that claim six months ago? “Yes, but I would’ve hesitated."

The recent tests included devices from:

Testing involved three steps. First, devices were tested to conform to the iSCSI standard. Next, Schaeffer’s team plugged the vendors’ products into a simulated device that could be tweaked to cause potential problems. Finally, vendor devices were connected to each other. The lab uses a home-grown software tool that is available as source code to consortium members, and which has been refined over the course of the plugfests.

Schaeffer says he had multiple iSCSI connections between targets and initiators working. However, he admits that the vendor devices were scaled back compared to what eventually will be required in the real world.

“A lot of people have functional but not complete devices,” he says. “They will work in the real world, but they don’t implement the entire standard. If someone wanted to set up a basic no-frills iSCSI network, it would be brick solid. But if you get a little wacky with it, with multiple connections, it might be a little iffy. iSCSI 1.0, yeah; 2.0, not yet. The bells and whistles would be 2.0.”

Many storage analysts expect iSCSI to become widely adopted this year or early in 2005. IP storage is cheaper, easier to manage, and it removes the distance limitations of Fibre Channel. Even so, Fibre Channel will likely continue as the connection of choice in the enterprise for at least several years, thanks to widespread implementation and performance superiority to iSCSI (see IDC: SANs Gather Steam and ISCSI: Next Big Thing or H-IP-E?).

Schaeffer, who runs one of the non-profit UNH-IOL’s 14 consortiums, says his iSCSI testing will continue even after iSCSI is adopted commercially. His focus will be on new devices and tweaks to the standard. He also would like to get some more of the major players involved.“It’s an annoyance that they all don’t participate, but not a concern yet,” Schaeffer says. “Eventually it will be a concern, because if we’re going to keep testing, we want everybody involved.”

The other major iSCSI test bed is Microsoft Corp.'s (Nasdaq: MSFT) lab, which certifies iSCSI products for compatibility with various Microsoft wares. But Schaeffer says Microsoft takes a different approach. “Microsoft has a bottoms-up mentality, and we have a top-down mentality,” he says. “They’re looking at, ‘Do they play nice with us?’ We’re looking at, ‘Do you place nice with the standard, and if not, why?' ”

— Dave Raffo, Senior Editor, Byte and Switch

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