UNIX is a ship very slowly letting in water. The rats aren't about to abandon it quite yet, but they are certainly checking where the life vests are stored.
The cause of the leak is Linux. UNIX may account for about a third of the server market, but its upstart cousin is slowly but surely eating in to that share. It's not that there's anything wrong with UNIX far from it. It's just that Linux is becoming increasingly capable of doing the less-demanding tasks that UNIX has historically been asked to do.
Vendors like Sun and HP are covering their bases by offering hardware with Linux as an alternative to the proprietary Unixes they sell. It's a tricky act to pull off. You can't go around binging up the benefits of Linux too much if you don't want to undermine your UNIX business, but if customers are going to move to Linux anyway, then you must make some noise in that department.
Stephen Bacon, a manager in HP's critical systems division, loyally defends his company's UNIX offering and insists the long term future for UNIX is bright. "UNIX is robust so if it is not broken, why change it? And UNIX does have some features than Linux doesn't have single-system RAS capabilities and the ability to deallocate failing processors online, for example."
Very true. But at the same time, he makes it clear that it's Linux that's the focus of many customers' attention. "What we are seeing is customers with new applications choosing Linux and also customers re-architecting older ones that were running on UNIX or mainframe systems."
And each time a customer does so, UNIX sits a tiny bit lower in the water.
While the old "if it ain't broke, don't fix it" argument in favor of UNIX is certainly a powerful one, there's no getting around the fact that, increasingly, a Linux-based solution is up to the job. UNIX is sufficient, but no longer necessary.
That in and of itself is not a reason to abandon UNIX in favor of an enterprise Linux distribution. But Bacon points to factors such as ISVs moving their products forward on Linux, or management policies to consolidate applications onto a common Linux platform, as drivers away from UNIX.
Although these are not arguments against UNIX itself, they are factors that make a move to Linux more likely.
But Linux does have one killer feature that is driving the switch: lower cost. Many companies are discovering Linux to be extremely attractive from a cost perspective. Take the experience of Sabre, a travel company that replaced Solaris with Red Hat Enterprise Linux (RHEL) running on x86 machines, resulting in lowering costs 90 percent (with a three-fold speed gain to boot). These potential cost savings, which include hardware maintenance costs savings, are not to sniffed at.
In fact, Bacon believes more companies would choose Linux over UNIX if only they realized it was up to the job. All that's holding them back he thinks are a couple of myths:
- Linux Myth No. 1: Linux cannot scale up to support large, enterprise workloads. If this is true, then many UNIX systems are safe. Using HP's Itanium-based Integrity servers it's possible to scale to 64 processor/128 core systems running Linux, Bacon points out. HP clients use such systems to run applications, including SAP (usually on SUSE Linux Enterprise Server (SLES) and Oracle E-Business Suite (usually on RHEL).
- Linux Myth No. 2: Linux can't reliably support business-critical computing.
This is a potential showstopper for Linux: If it's not reliable enough, then cost and scalability are irrelevant. The proof of the pudding, though, is in the eating, and a number of companies have reliably been lunching on Linux. Sabre's CTO Robert Wiseman says that since switching from Solaris to RHEL he has not had a single outage due to Linux on his systems, which handle 32,000 transactions per second at peak times and more than 12 million a day in total. Another travel firm, Amadeus Global Travel Distribution, powers its Fare Quote system (which handles 5,500 transactions per second at peak times) using a server farm of 16 processor servers running SLES.
Perhaps the sinking ship analogy is a little harsh. UNIX still has a huge presence in the data center, and this is likely to be the case in five or even 10 years time. So here's another analogy to think about: Linux is like a developing nation whose industrial base is rapidly becoming more sophisticated and whose workers still demand only minimal pay. UNIX is an expensive European or U.S.-based manufacturer. And we all know that when developing nations make high-quality goods at moderate prices, established manufacturers in developed nations with high costs see their market share shrink until all that remains is a very small area at the very top end.
If I were a rat, I'd certainly be trying on a life vest for size.
Paul Rubens is an IT consultant and journalist based in Marlow on Thames, England. He has been programming, tinkering and generally sitting in front of computer screens since his first encounter with a DEC PDP-11 in 1979.
This article was first published on ServerWatch.com.