IBM (NYSE: IBM) unveiled an expanded version of its eServer Unix "clustering" technology on Friday that it said doubles the capacity of its predecessor. The Cluster 1600 is a collection of hardware and software for pSeries Unix servers.

Often used by corporations in computing-intensive applications, clustering is the process of connecting multiple computers to make them work as one.

If a server in a cluster fails, cluster-enabled operating systems can move that server's processes to another server, allowing users to continue working while the first server is repaired.

The new offering is IBM's first cluster package for its Power4-based pSeries servers, which include the p690 and p670.
The cluster-computing market is very competitive, with Sun Microsystems (Nasdaq: SUNW) , SGI, Hewlett-Packard (NYSE: HPQ) and Dell (Nasdaq: DELL) all offering clustering software.

IBM's 1600 bundles high-end hardware and management software designed to make clustering technology easier to use. However, the technology, first developed for an IBM supercomputer , is expensive. Packages start at $2.4 million for two 32-way p690 servers, cluster-management software and a control workstation.

IBM said that clusters can also include entry and midrange pSeries servers, such as the p680, p660, and p630, which will be available later this month.

"This opens up all kinds of opportunities," Jim McGaughan, IBM director of eServer marketing, told NewsFactor. "Customers now can select from mid-range systems in the $20,000 to $30,000 class, all the way up to these very large servers, and interconnect them all together."

"They all appear as a single resource," McGaughan said. "They're all managed from a single point of control, and they can pick and choose how they want to divvy it up."

"More than ever, customers want to improve manageability and simplify their IT environments," IBM's vice-president of IBM's eServer series Surjit Chana said in a statement. "The IBM eServer Cluster 1600 lets customers reduce the number of servers in their data centers and manage hundreds of applications from a single pane of glass."

Other features of IBM's clustering software include multisystems management, remote management and performance monitoring through an AIX graphical user interface. In addition, the software includes the company's General Parallel File System technology, which provides shared access to files across nodes in the cluster.

Each server added to a cluster requires a $7,500 adaptor, which must be added when the server is connected. Clustering is largely used for parallel processing -- the technique of using more than one CPU at the same time to run a program. It is popular with companies because they can use existing PCs and workstations, and because it is relatively simple to add more processing power by adding more PCs to the network.

Clustering is also used for load-balancing -- the even distribution of processing and communications across a network so that no single server is over-burdened -- and fault tolerance, which is the ability of a system to respond to or recover from a hardware or software failure.

There are also rivals developing clustering technology for Linux.

In June, for example, Oracle (Nasdaq: ORCL) said it had developed a clustering version of its own database software that can run across multiple Linux servers. Oracle developed the technology with help from Dell and Linux distributor Red Hat (Nasdaq: RHAT) .

IBM's database software has had Linux clustering capabilities for two years, according to the company.