“The best source is the CBT CD-ROM, which contains Rick Fochtman's OS/360 distribution. This has not only the OS/360 distribution files, but also the source to the operating system and utilities, as well as some useful documentation. There are many, many other useful files and utilities on the disk, and it's a must for anyone wanting to experiment with OS/360, as well as any systems programmer on a modern OS/390 or z/OS system. Ordering information is at the CBT Tape site.”
It's a fun experience to install MVS 3.8j (apparently 40 years old by now), using the Hyperion fork, to get a taste of how utterly different mainframe computing was (and still is).
If you've never dealt with mainframes, which is extremely likely after all, you will be massively taken aback about how different everything is. A lot of the most fundamental terms you are used to, like "file" or "directory", simply don't exist. Some have equivalents with other names, but even if they do they're often so different that you barely recognize them at all... It's like finding a computer on an alien planet.
Interestingly, the later "midrange" AS/400 (or maybe also its predecessor System/36 which I don't know about) is also completely different from mainstream computing, but in something that I'd describe as the opposite way of how MVS is different.
While MVS lets you feel the bare metal at every turn (making such simple things as using the closest thing to a file, a "dataset", sometimes rather bizarre), AS/400 does the opposite and abstracts everything away. Going as far as having a 128bit unified address space, which addresses both RAM and hard disk storage and everything in between...
> If you've never dealt with mainframes, which is extremely likely after all, you will be massively taken aback about how different everything is.
Funnily enough my alma mater recently made Introduction to Mainframes a mandatory subject for a software engineering course. So if you can't use z/OS on a (very) basic level, you can't graduate. :)
Extract and run MVS 3.8j TK4- [1] on Hyperion [2] is a bit...hmm less time consuming then installing a barebone MVS, plus more tools, games, compilers...and basic tcp ;)
True, but you learn much more about the system installing yourself, and if like me you did not have any experience with mainframes... I think I'd have been utterly, utterly lost without that installing experience.
AS/400 is an interesting system. When IBM stopped supporting circa 1999 25 MHz PowerPC system at a friends company in 2010, I learned a bit about it in getting rid of it.
Other than CEs replacing hard disks a few times, and an Ethernet upgrade, it was undisturbed by anyone other than the end users. The server had restarted ~20 times, by power outages. Crazy stuff.
This machine at my desk is already emulating a Sparcstation 5, a Mac Pro and a Windows 2019 machine. I might give this a crack just so I have an excuse to try to get one of the 3270 terminal emulators running. Like x3270 or one of those things that used to float around. I assume you need to emulate a terminal concentrator somehow along with the mainframe itself?
Otherwise, a TN3270 client program such as x3270 is enough: Hercules makes TN3270 clients appear to the mainframe operating system as though they were display stations connected to a channel-attached establishment controller.
If you don’t want to install an X11 server, by the way, you can use the c3270 program that comes with the x3270 package.
I love the idea - if you look hard enough you can find an OS/390 or z/OS torrent - but most of the Hercules emulator documents haven’t been updated in twenty years and I don’t think there has been a software release in approx seven years. I’ve never been clear if the project is still active.
“The best source is the CBT CD-ROM, which contains Rick Fochtman's OS/360 distribution. This has not only the OS/360 distribution files, but also the source to the operating system and utilities, as well as some useful documentation. There are many, many other useful files and utilities on the disk, and it's a must for anyone wanting to experiment with OS/360, as well as any systems programmer on a modern OS/390 or z/OS system. Ordering information is at the CBT Tape site.”
That CBT Tape site is a sight to behold even if you have no plans to run OS/360: https://www.cbttape.org/. Bonus link: https://www.cbttape.org/funny/bug3.jpg