To users and analysts, the myriad Linux distributions are like penguins, the Linux mascot: The various species have different plumage, but under the feathers, they all walk like penguins.
Rather than being disappointed with a lack of breakthrough innovations, though, users say the technological differences among Linux distributions is a blessing. As long as the distributions are interchangeable, corporate users remain independent of their vendors.
Vendors can help users with support or consulting, but they can't hurt users by locking them in or forcing them to upgrade. That's especially true when Linux is used in network appliances, which are used for only one specialized purpose. In such cases, the basic tools available with every Linux variant are all that are needed.
"If Red Hat [Software Inc.] were to fall off the face of the earth, it wouldn't stop us from going forward," said Jeff Davis, senior systems programmer at Amerada Hess Corp. in Houston, which uses a massively parallel Linux cluster to render 3-D images of the seabed for oil exploration. Red Hat just happened to be the Linux distribution that information technology workers at Hess were most familiar with, he said. In addition, its name recognition made it an easier sell to management than other Linux variants.
At the San Francisco architecture firm of Gensler Inc., information systems Vice President Bruce Bartolf said he chose Red Hat because it has the greatest support from third-party software developers.
Although commercial competition has been intensifying this year, Linux vendors remain constrained from diverging technologically because they worry that forking, as Unix has, would confuse or divide users, said analyst Stacey Quandt at Giga Information Group Inc. in Cambridge, Mass.
Meanwhile, one of the few mandates of Linux's General Public License is that changes to the operating system itself must be made freely available to everyone else, meaning vendors must share anything that would give them a competitive advantage.
Lester Hightower, vice president of advanced open systems at ABC-NAC Rail Systems Group, said the choice of Linux doesn't matter on the server, because servers will run "a kernel, basic tools and then specific services such as sendmail, Apache or an RDBMS," he said.
At the railway signal system maker in Jacksonville, Fla., Hightower has swapped Walnut Creek CD-Rom Inc.'s SlackWare distribution out for Red Hat without much trouble and downloaded kernel updates from the Linux community rather than waiting for Red Hat.
It's going too far to say that the Linuxes are identical under the hood. Users with a need for multilingual Linux, for example, can look west, to Nuremberg, Germany-based SuSE Inc's. longtime support of European users, or east, to Brisbane, Calif.-based TurboLinux Inc.'s support for Asian languages.
Orem, Utah-based Caldera System Inc.'s OpenLinux 2.3 has important and unique features that made it a good choice for hotelier Cendant Corp. in New York, said technical lead Damon Covey.
One example is that OpenLinux is self-hosting, meaning the binary files and their accompanying source code match exactly. In some other distributions, source files require different libraries and interfaces. OpenLinux allowed Cendant to recompile files, such as drivers, with predictable and consistent results.