I found an interesting article in the May 2002 edition of Linux Magazine entitled Too Many Servers by Steven Vaughan-Nichols. In part it reads:
"I think Linux will become a brand-name operating system for millions of business users. But they're not. going to be running Linux on desktop PCs, they're going to be running appli cations on a Linux virtual machine (VM) running on a high-powered cluster or on a mainframe.
You could see signs of this coming change at this January's LinuxWorld. Shirts and ties far outnumberedtie-dyed shirts. The big news of the show wasn't that IBM was pushing Linux on the mainframe: they've been doing that for awhile now. And it wasn't their TV ads featuring Linux or their new slogan, "Linux is real business." The big news, according to Bill Zeitler, head of IBM's server group, is that out of the bil- lion dollars IBM poured into Linux, "We've recouped most of it in the first year in sales of software and systems." That's not, "Oh, some day we'll see a retu,m," or "Oh, it's worth it because of good will," that's "IBM is making money from Linux today."
x x x
How is it being done ? IBM is doing it by running Red Hat, SuSE, and TurboLinux as VMs on their S/390 mainframes and other "big iron" models. VMware is also in the picture with its ESX Server, optimized to run on IBM's Intel-based eServer xSeries systems.
Compaq and Platform Computing are using clustering to follow a similar path on the Alpha. In addition, there are at least four open source VM projects, Free VSD, Plex86, User- mode Linux (UML), and v server. Commercial efforts in the same line come from SWsofr and Ensim.
You might be asking, though, "Why bother with virtual machines?" After all, it's not as if your generic Linux box is going to run out of resources for ordinary server programs.
But there are several good reasons to go the VM route. One is security. While the Unix/Linux security model is strong compared to Microsoft's, mainframes are muchhard- er to crack. Even if a cracker does get root access to a single server running as a VM on the mainframe, he's still no clos- er to getting into other Linux VM servers or the mainfr~me operating system.
Another advantage VMs have is stability. Half a dozen Linux VM servers can crash, but the other two dozen will still hum along normally. A standalone Intel-based Linux server simply can't compete with that level of stability.
x x x
What's clear, though, is that Linux's biggest future role isn't as the revolutionary operating system for PCs; it's as the heart of corporate big-iron systems. There's something ironic about that, but it's the price of success. Linux is proving to be too good, too advanced for the desktop; instead its fate is to be the center of the enterprise. Who would have thought it?"
Comments?