"It won't happen overnight, just like the PC didn't take over right away," he says. "It's a fundamentally difficult thing for businesses to move from 60% [profit] margins--which is where the proprietary storage subsystem vendors are today--to around 30%, which is where clustered systems are trying to bring them."

Another challenge is that developing clustered products has already proven easier said than done for some established vendors, including Network Appliance (NetApp). Just over four years after its acquisition of clustered NAS intellectual property from Spinnaker Networks for $300 million, NetApp is still working to integrate enterprise data management features like SnapMirror with its clustered Data Ontap GX product.

So far, GX has garnered the most interest from users with specialized environments, such as Vancouver, BC-based special effects studio Image Engine Design. According to COO Peter Muzzers, the ability to scale the system quickly, rather than full software feature support, was his company's primary concern when it deployed the system.

"The one feature we're still waiting for is better support for SNMP for reporting and monitoring," says Muzzers. "There seems to be some provisions for it in the code--they're obviously trying."

"GX doesn't have all the data replication capabilities we'd like it to have yet," admits Jay Kidd, NetApp's chief marketing officer. "But it's a matter of how to prioritize our development efforts." Kidd says NetApp's R&D focus has been on developing features for its existing monolithic systems to broaden their appeal, but it does plan to offer a single OS based on the best of both worlds.

For now, that's still a ways off. "We've found that the clustered storage market is still typically limited to single homogeneous workloads," says Kidd. "It's an important market, but it's not a mainstream market yet."

--Beth Pariseau