Are these systems bootable?
It has been so reported - in this same space IIRC
I see all the source, but recall previous discussions
about how bootstrapping them was tricky, or at least involved a large number of
steps, each of which wasn't bad, but the whole path wasn't well mapped out.
I believe that is also correct. Been a ToDo item of mine to try to get them running. Supposedly people used V8 to get V9 running.
For V[67] we at least have boot tapes from back in the day, and V5 has a bootable disk image...
Yep and it helps, some of us did it back in the day.
The problem has been expressed, that V{8,9,10} like Plan9, were locked away for whatever reasons. They were all created post-Judge Green when the behavior of AT&T formally WRT to the rest of the world changed. I don't think the people in 1127's attitude changed (certainly not of my friends that I interacted with) but what they could do was more constrained.
Before the 1956 consent decree, AT&T corporate was not allowed to be in the computer business, post-Judge Green they were actively trying to be and their SW was formally System III and the later System V versions. BTW: AT&T was unique in this behavior. IBM and DEC did it too. One of my favorite stories (that I personally lived) is that of Motorola, which became the 68000. When I first got it (at Teklabs) it did not have a number - which much, much later beget the 4404, it was explicitly told to us that it was a toy and it was not committed. We managed to get approx $100 of them to make the first Magnolia machine But the original developers had given a couple of them to the research teams of a few of their friends - the 6809 was the official product. Famously, when IBM asked Moto to bid on a processor for what was to later become the PC, they had been playing with the future 68000 in NY and Conn, already. When the folks came to Austin, IBM was pressured to use the 6809 by Motorola marketing, and officially told that the other chip had no future and was an experiment.
I always looked at V{8,9,10} and Plan9 in the same way. BTW: I also think that's part of why BSD got such a lead. AT&T Marketing kept the 'consider it standard' stuff in people's faces with System III and later Sys V. Many users (like me) and our firms wanted no part of it. If AT&T had been offered V{8,9,10} or Plan9 under the same basic terms that V7 had been, I suspect that the story might have had a different ending.