Interesting article on NT server clustering:
Storage Vendors Muster Cluster Solutions
(12/04/97; 3:00 p.m. EST)
By Chuck Moozakis, InternetWeek <Picture>While IT managers wait for Microsoft to deliver a more robust version of its Cluster Server technology, two storage vendors are rolling out product lines that can lash together up to a dozen NT servers sharing a single storage device.
The suppliers, Storage Computer and Legacy Storage Systems, are laying the groundwork for NT clustering, said Tom Lahive, senior analyst at Dataquest, in San Jose, Calif. "One of the benefits of clustering is to enable servers to share data. When you have a centralized disk array that can share NT servers, everyone has access to the same data pool."
In essence, clustering creates a quick-response backup system in the event a server fails. With clustering, two or more servers are tied together. If one goes down, other servers in the cluster pick up the slack; critical data is thus shared among servers, and failover is immediate and transparent. That's exactly the type of protection data administrators are seeking.
While clustering is available on the Unix platform, managers are still waiting for equivalent NT clustering solutions. Microsoft's Cluster Server technology may eventually provide the answer administrators are looking for, but the current version -- which can support only two nodes -- is too rudimentary to link the number of servers needed for mission-critical applications.
"The buzzword is adding scalability. By adding nodes to cluster you increase performance," said Greg Scorziello, senior vice president of worldwide sales and marketing at Storage Computer. The Nashua, N.H., vendor next week will add NT compatibility to its OmniRAID Cluster Array. Users can configure as many as 12 direct host connections or up to 24-way NT servers, enabling multiple devices to share a single storage pool or multiple storage partitions.
OmniRAID Cluster Array is based on Storage Computer's Virtual Storage Architecture, which permits the array to store and retrieve data more efficiently, Scorziello said.
"We stripe the data like everyone else, but our software" makes the array focus on the transaction requested, he said. By making OmniRAID "transaction-centric," rather than hardware-centric, the device can handle multiple servers, he added.
"As users deploy more strategic applications, they have to put these apps on each NT server individually," Scorziello said. "Then there is the Internet. There is a lot of robust data, and this type of data kills hardware-centric storage devices. If you have to use RAID 3 for visuals and RAID 1 for text, when you start merging the two, it kills performance." OmniRAID avoids that performance drop, Scorziello said.
OmniRAID is available immediately and has a 1-terabyte capacity. It is priced at between $50,000 and $250,000, depending upon the amount of storage required. An optional mirroring application, OmniForce, is also available.
Legacy's ClusterStor, meanwhile, is an eight-server device that attaches directly to a company's network, using Legacy's disk array, tape library or CD server as a storage medium. ClusterStor, which will be released early in 1998, bundles from two to eight NT servers and includes an embedded cluster mirroring utility, according to Legacy president John Whyte.
"Customers aren't yet looking for a total clustered environment," Whyte said, describing ClusterStor's niche. "They usually have only a few applications that they need fault tolerance, and they don't want to pay redundant costs for an additional server that will serve only as a failover."
Direct network attachment of storage devices has been thwarted somewhat by insufficient network bandwidth, Whyte said. With the advent of higher-capacity connectivity technologies such as Fibre Channel and Ultra SCSI, products such as ClusterStor can be deployed more effectively.
ClusterStor will be priced at $30,000. |
