For 35 years, the Unix operating system has been a mainstay of the computer industry, from its origins as a time-sharing system used by horn-rimmed academics to its central role running some of today's most powerful servers. But enthusiasm for this sophisticated piece of code is in decline as sales flatten, while Linux, the Unix-like alternative, thrives. Which leads to the inevitable question: Is Unix itself on the wane?

The past few years haven't been kind to Unix. Two longtime commercial backers, Hewlett-Packard and IBM, have diverted resources and energy into promoting Linux at the expense of their Unix offerings. Sun Microsystems' Solaris wasn't selling so well, so it embarked on an open-source strategy to give it away. SCO Group, which owns the venerable Unix System V code base, is distracted by intellectual-property lawsuits against IBM and other Linux backers. John Loiacono, Sun's senior VP of software, recently referred to HP-UX and IBM's AIX as "the dead Unixes." Competitive bluster to be sure, but Loiacono may not be far off in that assessment.

In the '90s, Unix was set to become the dominant operating system for heavy-duty computing, with Windows the only threat. But the rise of Linux and steady maturation of Win-

dows have darkened Unix's future. Spending for Unix licenses and maintenance was just over $2 billion in 2004, down $51 million from the year before, according to IDC, which predicts the market will be stagnant over the next few years.

"Run anything we can on Linux"--that's Ohio Savings Bank's strategy, says enterprise information manager Miller. Photo by Russell Lee

With hardware included, the market is bigger, yet still struggling. Unix server revenue (IDC calls it "factory revenue") amounted to $3.9 billion in the third quarter of 2005, a 0.4% decline compared with the same period a year earlier, while unit shipments dropped 13.7% year to year. By comparison, Linux server unit shipments jumped 20.5% in the third quarter of 2005, compared with a year earlier, and Windows server unit shipments climbed 15.3%. There was also this milestone in the third quarter: Windows servers accounted for the largest slice of the overall server market for the first time ever, according to IDC.

It doesn't help that most commercial applications today are written for Windows or in Java, which runs well on Linux computers, rather than aimed at a specific Unix system.

Longtime Unix customers are bailing out. This past weekend, Ohio Savings Bank planned to move its core mortgage-processing application off of five megaservers running HP-UX to a cluster of low-cost Linux servers. As a next step, it's considering discontinuing the maintenance agreements covering the retired HP-UX servers. The bank already had transferred its Oracle database from HP-UX to Linux systems. At some point it would like to move its largest system, a data warehouse on a 12-CPU server running IBM's AIX, to a Linux cluster as well.

"The only place we still use HP-UX is where the application is not available under Linux. Our goal is to run anything we can on Linux," enterprise information manager Tony Miller says, noting that the strategy has cut maintenance, development, and operations costs for the bank. Ohio Savings uses 23 Linux servers, 13 for database hosting and development and 10 to host production applications. Miller estimates the bank could save $80,000 to $100,000 annually if it phases out some of its remaining HP-UX maintenance agreements.

Not Dead Yet

IT professionals are a pragmatic bunch, however, so it will be many years before Unix slides into oblivion. HP routinely supports HP-UX releases for up to 10 years, while Sun maintains backward compatibility from one Solaris release to another to ensure longevity. Unix's decline will be like watching ice melt on a 33-degree day.