In case you hadn't noticed, I'm very excited about what has been accomplished by the two porting teams and by the other contributors. Getting Linux to run, and to run very well, on hardware this foreign is no mean feat and these folks deserve a virtual beer for one seriously cool hack. I learn something new every day from these folks, and I am humbled to be in their company online.

There is an extremely active Internet community surrounding the Linux on S/390 ports (plural), and the Marist College e-mail list is a central part of that community. Most of the development effort is focused on IBM's port right now, but Linas Vepstas is a "regular" on the Marist College list and a good deal of the discussion applies to either port. There are some extremely smart people, and some damned fine hackers, on that e-mail list.

Naturally, you'll want to have TCP/IP networking services running right away. The standard boot images from Marist College support the IBM "OSA" network adapter hardware which is in common use, but for now each Linux image running needs to have its own dedicated OSA port (fortunately, this is a multiport board, so that's usually possible). Several methods are being discussed as to how best to share the OSA adapter hardware across multiple Linux images.

By now, I hope you're convinced that mainframes and Linux have a great future together. Even if you don't have access to an IBM mainframe, you have to admit this is one groovy hack! Now let's take a further look into how it works and some of the things yet to be done.

Impressive as they are, these demonstrations are really nothing more than lab curiosities unless they accomplish something useful in the real world. Why would you want to run Linux on a mainframe, especially if you are a manager or business person?

About a month ago, our resident mainframe wizard came to see me and said he needed some help with a Linux problem. Now, I should point out here that this didn't surprise me. Several mainframe mavens that I know are very interested in Linux and Java and other new technologies. I've found the mainframe crowd to be much more open to new ideas than a lot of my PC-oriented colleagues who think the world ends at the edge of their LAN. So when Ralph asked me for Linux help, I assumed he had installed it on a spare PC to play around.

If you've read all that came before, you have probably decided by now that I am some kind of mainframe bigot, that I'm one of those people who likes to sit in a glass room with a raised tile floor and

But wait, there's more! It turns out that, with the "PR/SM" feature mentioned previously, the S/390 hardware can actually divide itself into units called Logical Partitions, or LPARs. Say you've got an eight-way S/390 machine. You

I first started working with IBM's mainframes in college in the early 1980s. We had two systems then: MVS for running batch jobs from punch cards, and VM for running interactive programs on a terminal. I hated punch cards (everybody did) but I was impressed by what you could do with MVS.

As Appearing in LinuxPlanet, February 23, 2000. This was one of the first widely-read articles about running Linux on IBM mainframes, and its success helped to launch a major career change for me.