Vixel, LSI Logic Introduce SAN Cluster

SANs havegained acceptance as reliable storage systems for high-end enterpriseenvironments, but vendors are having a difficult time pushing the technologyinto midrange networks. A partnership between two storage companies hasproduced a single solution to get midrange SANs up and running as fast aspossible.

Vixel andLSI Logic recently announced a SAN-in-a-box solution that contains a FibreChannel hub from Vixel and a RAID storage system from LSI Logic. The kit alsoships with a Fibre Channel Host Bus Adapter (HBA) from Qlogic. The SAN Clusterwas designed specifically for Windows NT/2000 server clustering environmentsand to make SAN technology easy for new users.

“The wholeidea is to give people access to high-end storage resources,” says WallyMiller, product manager for hubs at Vixel. Miller says administrators are awareof SAN’s usefulness, particularly in clustered environments, but are scaredaway by cost and configuration issues. As a result, the companies decided towork together to create low-cost, preconfigured SAN units.

Miller saysVixel and LSI Logic decided to focus on clustered systems because thisenvironment gains the most benefit of SANs, and it is growing. Many users haveadopted two-node failover systems for applications such as Exchange, and needthe ability to share storage between the servers.

“It’sreally, really knocking down the resources you need to deploy a SAN,” Millersays. The only thing the kit does not include is the server, which needs to berunning Windows NT or Windows 2000 Advanced Server. The companies plan tosupport other operating systems in the future, but Miller says the Windowsplatform offers the most users who wrestle with the issues the companies aretrying to address. “We wanted to pick a fairly large target,” he says.

Vixel’s 2100Managed Hub with Zoning provides much of the value for the box, Miller says.The hub blurs the line between a hub and a switch, performing many of the sameduties of a switch, but is priced as a high-end hub. The functionality and costlowers the barrier to entry for users.

Accordingto Steve Widen, research director of storage software at IDC, Vixel and otherswitch vendors are making plays for the lower end of the SAN market by addingswitch functionality to the lower-cost hubs. Although Vixel and others attemptto gain attention by increasing port counts for the high end of the market, thecompanies’ strategic plays are really at the low end. “Hubs are much lessexpensive than switches on a per-port basis,” he says.

“Historically,hubs have been primarily repeaters,” Miller explains, noting that the functionof most hubs is to send Fibre Channel data to multiple wires in the SAN.Vixel’s hub offers the ability to detect nonsense garbage streams and avoidstoring useless data or clogging bandwidth with errors. If the hub detectserrors, it will stop transmitting data. “It’s got some intelligence that you’venever seen before in a hub,” he says. Widen agrees that Vixel is addingimportant functionality to hubs. “There wasn’t a lot of intelligence in hubs,”he says of older products.

Zoning isthe functionality that really sets the 2100 apart from traditional hubs. Millersays users frequently deploy switches rather than hubs for zoning ability. Withzoning, a SAN can dedicate part of the network to a single task. “Typically inhubs you had to share the bandwidth. In switches, the ports have their owndedicated bandwidth,” Widen says.

Widen andMiller agree that zoning can improve the reliability of mid-level SANs. For example,if an administrator is backing up data from disk to tape, he can dedicate partof the bandwidth exclusively for the backup, reducing the incidence of errorsor interruptions by other network traffic. Since Fibre Channel has littletolerance for interruption or latency, dedicated bandwidth is critical forusable, reliable backups.

The nexttask for Vixel is certification by Microsoft. Miller has no doubts that theunit will perform on Windows NT/2000 systems, but he hopes that Microsoft willendorse it as a certified solution. The vendors submitted it for review to theMicrosoft Hardware Qualification Lab.

Vixel Corp., Bothell, Wash.,
LSI Logic Corp., Milpitas, Calif.,