The Dangers of a Fractured Linux

One of the major advantages Linux has to offer is cross-platform

functionality. Far from being a PC operating system that has been

extended for other uses, it runs on cell phones, mainframes and

everything in between.

This offers IT departments the possibility of using Linux to consolidate

resources into a single skill set, or at least a single OS.

The danger, however, is that since developers are free to conduct

extensive customization, it may fork into a number of incompatible

versions.

”The differences between the versions of Linux can increase the level of

effort on the part of the system administrators as software installations

and verification can vary from system to system,” says Rob Pennington,

CTO and head of the Innovative Systems Laboratory at the National Center

for Supercomputing Applications. ”The different OS types and versions

make it very time consuming to verify that all the pieces (libraries,

compilers, file systems, etc.) work together as expected.”

Pennington has five Linux clusters under his control, including a 16

Teraflop Tungstun (W) cluster, which runs Red Hat Linux on 2560 Intel

Xeon processors. Several of the clusters are part of the TeraGrid, a

40-gigabit-per-second network, linking computers at nine universities and

national laboratories.

”A researcher should be able to use any of the systems without having to

know the paths to all of the necessary tools, the methods to submit jobs

for execution or the paths for the storage systems on the systems,” he

adds. ”This would appear to be simple but it becomes very complex when

this same type of goal is applied to multiple sites, such as those within

the TeraGrid.”

But the problem of Linux compatibility doesn’t just affect those

developing high-end research applications. Software vendors also are

significantly impacted.

There are more than 380 different Linux distributions, after all, and

developers need to make sure their products function well on at least all

the major ones in order to make their efforts profitable.

”In the beginning, end users, application developers and system

administrators were delighted to have the flexibility to make very

personal corporate decisions,” says William Hurley, senior analyst for

Enterprise Strategy Group in Portland, Or. ”Though there is a lot of

freedom in that, the ultimate long-term goal is to standardize on a class

of technologies, not just within the organization, but on explicit or de

facto industry standards so it is easier to apply complimentary

technologies.”

Kernel Control

The danger with Linux is not at the kernel. Although there are many

independent developers contributing their labor, what gets released

publicly is firmly under the control of Linus Torvalds.

”At the kernel itself, the community is very disciplined, so you don’t

see the kernel forking,” says Bill Weinberg, an open source architecture

specialist who works for the Open Source Development Laboratory (OSDL) in

Beaverton, Or. ”But there is the potential for divergence among some of

the Linux distributions, which makes it challenging for vendors to ship

shrink-wrapped software without having a lot of installation and

maintenance challenges across distributions.”

To make the job easier, several groups are creating standards and tools

to ensure software interoperability. They include: