Had the dubious joy of managing Domain/OS Unix children inside the Apollo virtualisation method of the day. Along with Nixdorf, these systems were all through Civil Engineering and NMR facilities at the university campus. And, just like Nixdorf they came with multiple open CVE (didn't exist as a term of art at the time, but lets ignore the anachronism) such as the games user, well known passwords, root sendmail, you-name-it.<p>Nice enough CPU and memory. Not a very nice Unix experience, analogous to HP-UX it was complex, and a bugger to configure C code on if you came from BSD land (Ultrix, SunOS/Solaris)<p>Sockets felt like a badly coded bolt-on. They really wanted to pretend the internet protocol stack wasn't there.