Technically, the post title is a lie. Having such an item would be impractical for me as it would take up too much space in my tiny flatshop (a hybrid flat/workshop type thing), and would cause the disk in my electricity meter to spin so fast that it could be used for sawing wood.
What I really have is a VMS machine, which is running on a simulated VAX 3900, which in turn runs on my puny Ubuntu 10.4 Linux machine (puny as in the hardware spec is pityful).
This is achieved by using something called SIMH, which simulates all manner of old DEC hardware, a copy of the OpenVMS Hobbist Kit, some OpenVMS licenses, and a copy of Paul Wherry’s guide to getting a VAX/VMS system running under SIMH.
To get SIMH working with Ethernet support, libpcap needs to be installed. To build this, flex, bison and m4 need to be installed. So these files need to be downloaded and copied to your linux machine:
Once these are on the linux box, should be installed as per the instructions with the packages in the order: flex, bison, m4, libpcap. With these installed, SIMH can be compiled as in Paul Wherry’s guide.
Instead of placing the files in /usr/local/vax, I placed the files in /usr/local/blinkyvax, and adjusted the paths in the vax.ini file for accordingly. This is because my eventual plan is to have four virtual VAXen running in a cluster named after the four Pacman ghosts – Blinky, Pinky, Inky and Clyde).
Getting hold of the OpenVMS media can be problematic, as the only legitimate way to get them is from Montagar Software for $30. Luckily, i was given the disks by someone who couldn’t getthem to work.
The easiest way to get hold of the Hobbyist Licenses is to go through DECUServe. To do this, telnet to eisner.decuserve.org, and login as REGISTRATION. Once this is done, you’ll be sent your membership number. This can be used, after about a week, on the Licensing page, to get your licenses. You’ll need the “OpenVMS VAX Base” and “OpenVMS Layered Products” licenses.
The SimVAX currently runs fine and can communicate with the other machines on my house network (through libpcap which wangles the ethernet card into promiscuous mode), but it cannot talk to its host machine (the one on which the simulator is actually running).
Sorting this niggle out is the next step, after which I can take another step forward in realising my dream of having my very own VMScluster.
Which sort of begs the question: Why?
Well. VAX/VMS was the second real multi-user operation system I ever got my hands on, and the first one I was actually paid to work with. Sometimes I get a little nostalgic. And then I get carried away.
As for the first multi-user OS I used, PR1MOS: there is an emulator out there, and if it ever becomes Open Source, I’ll be running that on my machine too.