As he began building National Gypsum's e-commerce site, Mike Brannon set up a server for order tracking, then one for PDF invoicing and another for patch testing. Launching separate servers for each additional function became habit forming, and costly, he says.

Three years and 53 servers later, Brannon has found himself with dozens of servers with underutilized processing power. And each box meant more equipment to manage, plus more downtime to deal with. "If you have to replace a disk drive, memory or a power supply, you're down for that time," he says. Moreover, many applications could have easily run on a 350-MHz Pentium III, but every time a hardware lease expired, he was forced to upgrade to a more powerful machine.

The senior manager of Internet technology has cured his bad habit with VMware's ESX Server partitioning software, a server consolidation fix he projects will save his company $5,800 per month on hardware leases. Brannon retired the 53 HP DL360 servers, and replaced them with an eight-processor IBM X440 production server, and a four-processor HP server for testing.

VMware's virtual machine software, which lets customers run multiple instances of an operating system and multiple applications on a single Intel processor, is one of several new tools that offer some form of server virtualization. Others include:

•  Software from Opsware (formerly Loudcloud) automates provisioning, change management, patch management, application deployment, and other server and application operations across multiple data centers.
•   Think Dynamics' Think Control Suite creates a pool of server resources and uses policies to automate provisioning of those resources to meet unexpected demand shifts.
•  The TopSpin 360 Switched Computing System provides a switch module that dynamically provisions virtualized memory and CPUs, storage and networking I/O, including 10-Gigabit InfiniBand connections.

The billion-dollar server automation market has grown in response to years of unbridled server proliferation, which drove customers to want to more efficiently manage their server resources, says John Humphreys, an analyst for IDC.