I am not old enough to have used those machines in real life. I have seen some of them in real life, but only as a child. However, I was interested in computer history -- and I had been for quite some time (after stumbling upon ESR's edition of the Jargon file) when I ran into SIMH.
This was back when documentation was pretty scarce, and Internet images slow. I got SIMH on my home computer by relying on floppy disks and a very understanding internet cafe operator. Shortly after, I got a dial-up connection, and managed to lug a few of the historical UNIX images, and boot them in a PDP-11 machine.
I remember being astonished at how much could be achieved in (what seemed to me, back in the late 90s/early 00s) so little memory and with so little computational power. It's what got me interested in the whole "doing less with more" business. Many years later, it turned out to be useful knowledge; when I got my first job writing device drivers for a really tiny RTOS, 48 KB of flash and 4 KB of RAM seemed like a reasonably comfortable space to write code in.
A few years later, I also got a hold of an OpenVMS copy -- which was actually pretty complicated because it involved signing up for DECUS Munchen (I still have my membership card!), which was not very easy considering that I was well under 18 and all the German words I knew were "Danke", "Gutten" and "Tag". I don't remember if SIMH or another emulator already had pcap-based networking support back then, but in any case, I ran a small OpenVMS machine and offered shell accounts to a few curious folks. The whole thing didn't really take off since the machine doing the hosting was the one I used every day for general computer stuff so...
I think the other emulator I had tons of fun with back then was GXemul ( http://gxemul.sourceforge.net/ ). Warmly recommended, even today. It's a glimpse into interesting times -- I'm tempted to say "better times", but nostalgia is a little treacherous.
Definitely puts things in chronological perspective to boot up something from that era (1986) and find it to be just about as functional as the base system today..
This is in contrast (imho) to v7/32v from only a few years prior which feels very 'incomplete' as compared to a modern system.
(I figure if you enjoy this tutorial you'll probably enjoy trying that one out too.)
To OP: The networking is a really nice touch. I didn't even attempt anything like that so kudos to you.
"Another alternative to direct pcap and tun/tap networking on all environments is NAT (SLiRP) networking. NAT networking is limited to only IP network protocols so DECnet, LAT and Clusting can't work on a NAT connected interface, but this may be the easiest solution for many folks."
But if you do this don't you get 4.3?
I am going to have to try that one over the weekend! ;-)
This was roughly equivalent to the system I used in high school, and I laughed out loud when I discovered that 7.0 wasn't Y2K-compatible. The math teacher who taught the computer classes was warning us about two-digit year values back in 1981!