This is because these versions of Linux will run well on SMP (symmetric multiprocessing) boxes with 32 or 64 CPUs, traditionally a weak point for earlier versions, Coekaerts said. Instead of buying "big iron," companies can now field commodity SMP boxes in clusters and save a bundle.
"Actually, there are some customers that have done this," he said. "So they have, say, a 64-way UNIX system and replaced it with a 60-node Intel Linux cluster and they get the same or better performance for a lot cheaper."
The SAN is important because it decouples the OS (operating system) from the data it is crunching, giving CIOs a confidence they are not playing roulette with their company's mission-critical elements. And moving from UNIX to Linux means you have the in-house expertise (with a little bit of re-education) to run Linux effectively since Linux is based on UNIX. Windows admins, on the other hand, may have a much harder time making the switch, Tierney said.
"You can't take a bunch of Windows people ... and ask them to (port) you mission- critical apps to Linux," he said.
When Tierney directed such an upgrade in his previous position as vice president of technology for a $200 million company, he saved $300,000 in hardware alone by moving from proprietary Hewlett Packard UNIX boxes to commodity Intel hardware, he said.
On the application side there is good news as well, said Terry Collings, an instructional technologist at Muhlenberg College in Allentown, Pa. and the man responsible for the college's Linux boxes. Today, there shouldn't be too much trouble getting programs ported over to Linux from UNIX.
There also is a lot of open source software (OSS) being written today that can handle enterprise needs. "If there's an application available for whatever you want to do in Linux, I don't see why there's even a big debate" about switching, he said.
For a higher degree of comfort, you can also look for enterprise-class Linux certifications on enterprise software, said Tierney. Oracle, for example, develops all of their new products on Linux, said Coekaerts.
Linux is also making great strides in data centers running sever-based applications since Linux is easily scalable, uses commodity hardware (this is where a majority of the savings come in) and requires no licensing fees, said Bill Weinberg, open source architecture specialist and Linux evangelist for the Open Source Development Labs (OSDL).
"A lot of people move to Linux just to make their data center computing resources more scalable at a lower cost," he said.
But there are three areas where all the experts agree Linux is probably not a very good fit, although not necessarily for technical reasons. The first is if you have a smooth-running infrastructure and aren't looking to scale or upgrade. This is basically the "If it ain't broke, don't fix it" mentality.
The second is if you are running a proprietary stack (like Windows) and don't have in-house UNIX or Linux expertise. This can cause more problems than its worth. Although, Weinberg points out, Linux is not an all or nothing proposition, so there may be areas where it will work if you look around.
Greenfield expansions are particularly good places to start using Linux or in closed-loop environments not running Microsoft Office, like a retail outlet or manufacturing floor.
And, lastly, the desktop. Too many workers are too imbued with Windows and Office productivity software to make the switch worthwhile, said Tierney. Technically speaking, it's not a great challenge to run Linux desktops, but since OSS functionality has a way to go before it catches up with Window's products, you will probably run into more employee resistance than it's worth.
"As a CIO, the reality is it's not worth the effort to switch off Windows Office," said Tierney. "You're helpdesk support of that base desktop application can be the biggest source of complaints and frustration from the user base. You've got bigger things to deal with."