Linux for enterprise applications is among the 6 hot technologies for 2006.March of the penguins: Linux moves from low-end e-mail and Web servers to running business-critical corporate applications.Although having an open source strategy is becoming common in many enterprises, users and analysts say 2006 is the year the penguin flippers will hit the water in terms of Linux's evolution into an enterprise-application server platform. Linux usage started with lower-level admins, deployed on individual desktops or small boxes. Then it moved into e-mail, file-and-print and serving Web pages. Now those who use Linux say the time is right for the operating system to be running key corporate-software packages, including large databases, financials, sales, medical records and a host of other business-critical systems.While some companies are expanding Linux's role from smaller to larger tasks, others are going straight to the core with the platform. At Germany-based Commerzbank, for example, the only place Linux runs is in the company's data centers, hosting core Oracle financial, ERP and database applications. The bank, which has 32,000 employees in 700 branches worldwide, moved to Linux when the IT staff found it hard to run new applications on its aging network of HP True64 Unix servers running on 64-bit Alpha processors originally developed by Digital."We would get a vendor to come in with a nice business application or a nice utility that might help the bank, and when we'd ask if it ran on True64, it was usually not the case," says Rich Arenaro, Commerzbank's vice president of IT.Because of Oracle's strong support for Linux, the bank decided to try Oracle on Linux for most of its back-office business applications. The first hurdle in migrating off a stable, long-used Unix platform to Linux was convincing bank executives that it was a safe move."Words like open source really stuck out with [management]," Arenaro says. "They might have seen open source and thought the environment was just a free-for-all."What won over the executives was the flexibility of Linux running on the Egenera BladeFrame platform, Arenaro says. Egenera servers are racks of dual and four-way processors that attach to storage and can be set up and converged on the fly. Using Red Hat and Novell SuSE on the Egenera platform lets Arenaro virtualize server instances and deploy them where needed. Every server image boots from the company's storage-area network (SAN), and all images are backed up across the company's data centers in New York and Germany. This lets the bank run an active\/active disaster-recovery setup, where the main and back-up sites are serving live users. If either site goes down, more server images and applications are pulled out of the SAN and put on the Egenera blades.Although the hardware and software runs smoothly, Arenaro says the support model for Linux may not have grown up as fast as the power of the technology for supporting core applications. "What I would welcome is more of a connected partnership on the hardware-vendor side," Arenaro says. He would like this, because he still has two support contracts. "There is nothing formal in place from our standpoint," he says. "I'd like to have one contract that I can ultimately point to if need be. There's always potential for finger-pointing," when dealing with hardware and software vendors. "Not that this has happened. But it always could," he says.Another organization that has only known Linux as a core-applications platform is the Cambridge Health Alliance (CHA), in Cambridge, Mass., which manages hospitals, clinics and outpatient facilities in greater Boston. When CHA's IT staff was looking for a new ambulatory-care system (the software used by doctors to track the records and other data of patients who visit CHA's clinics and outpatient facilities), they selected a software package called EPIC, which is among the leading products in this area.IBM, Sun and HP were presented as options for running the software. However, "no one was really liking any of these choices," says Seth Sladek, manager of systems engineering at CHA. The Linux option was explored, and the cost and performance benefits became obvious."It wasn't so much a pure cost decision as it was an overall-happiness decision," Sladek says. "We didn't want to be locked into these vendors" because of their proprietary hardware and support systems. "EPIC on Linux and Intel ran as well as, and in some cases better than, commercial Unix servers," Sladek says.NOT HOT: Linux on the desktopDespite efforts from a number of vendors, Linux on the desktop has little traction outside of rogue users. Analysts say there really isn\u2019t a good business case for a company to ditch Windows, and simply disliking Microsoft doesn\u2019t qualify as business justification for a wrenching move that disrupts every desktop and every application that runs on it.That's not to say cost was not a factor: After comparing quotes for EPIC on Linux and the major Unix brands, Linux beat them all, coming in at least half the cost.Application vendors that Sladek and CHA Systems Operations Manager Daniel Doherty deal with are becoming more receptive to offering their wares on Linux, as demand has grown from customers such as themselves. Because many healthcare vendors are Unix-focused, the transition is not very hard. "Vendors that have Unix familiarity have tended to be more willing and easier to deal with, in terms of porting to Linux," Doherty says.CHA is looking at moving its clinical risk-management system software and a new pharmacy system-management application to a Linux server. "If we're going to deploy a mission-critical application, it's going to be on Linux going forward."