Stratus brings fault tolerance to Win 2000 users

Microsoft has been preaching availability as one of the hallmarks of Windows 2000, while Stratus Computer is out to define just what that means.

Stratus, best known for its fault-tolerant hardware that powers such critical systems as those at the Nasdaq stock exchange, recently unveiled a new line of machines designed to run Win 2000. The ftServer, which comes in two models, is designed to guarantee a maximum of 1 to 5 minutes of downtime per year.

Both boxes have been specially designed for Win 2000, including fine-tuned device drivers, and are priced to compete with the cost of setting up a traditional PC cluster. Clustering allows enterprises to link numerous PCs to ensure availability of applications.

Traditional Stratus computers, which run the company's proprietary Virtual Operating System and HP-UX, are designed to be fault tolerant with pairs of internal processors running in parallel. If one pair fails, the other keeps going.

Stratus officials say this is a benefit over clustering failover technology, which requires scripts and logic to recover from a failure. The Stratus hardware is designed to prevent failures, not recover from them, according to company officials.

"The level of complexity rises the bigger a cluster gets," says Vernon Turner, an analyst with IDC in Framingham, Mass. "With a single box, there is less management needed, fewer administrators and less overhead. We see more and more applications going to NT and Windows 2000, and Stratus fills a piece of the marketplace."

With the new line of ftServers, Stratus will use the same fault-tolerant concept as with its traditional hardware, except that failures can be detected on single processors. Processors are installed in pairs, and if one processor fails, the other continues operating.

Stratus also has a unique internal management system. If a processor fails, the computer contacts Stratus, allowing the company to remotely diagnose the problem and send replacement parts to the customer overnight.

"This is a reliable system, but the operating system will still be the single largest point of failure," says Richard Fichera, an analyst with Giga Information Group in Cambridge, Mass.

To attack that issue, Stratus has confined device drivers to its own distinct boundaries for memory usage, so if they fail, they won't take down the entire operating system. The drivers are for such devices as PCI adapters and any communication or I/O in the software.

The ftServer will be available in two models, the 5200 and the 6500.

The 5200 comes in a one-way (two processors) and a two-way (four processors) 550-MHz Intel Pentium II Xeon processor that is priced at $23,300 and will ship in September.

The 6500 is a one-, two-, three- or four-way 700-MHz machine that will use Intel's forthcoming large cache Pentium III Xeon processor. It is priced at $30,500 and will ship in October.

Either model can be configured with up to 2M bytes of cache, 16 PCI slots and 48 RAID I disks. The models can be run in dual modular redundancy (two processors working in parallel) or triple modular redundancy (three processors).

Stratus: www.stratus.com