I've been on a Data General Aviion restoration binge lately and re-familiarizing myself with DG/UX.  In my case 5.4R3.1 running on a MC88100 based AV/300 and MC88110 dual core AV/5500.  The more I experience, the more I am impressed.  There are a few things about the system that seem impressive.

- Despite coming from a System V core, there is a lot of BSD influx - especially on the networking side.  This is a personal taste issue as other ports have tried to mix the best of both worlds.  But after a prior month-long Sun/Solaris restoration binge of similar era hardware (Super/Hyper/Ultra SPARC) and software (SunOS 4 through Solaris 9), DG/UX is a welcome and refreshing change!  Especially out of the box.

- It has a system of file security that seems unique for that era - at least in my experience - of explicit and implicit directory tags with inheritance.  There is even a high security extended version of the OS.

- It has a built-in logical volume manager supporting multiple virtual to physical disk mappings, striping, mirroring, and even archiving - something several entire sub-industries were created for in other ports.  I am guessing this contributed to EMC's purchase of Data General for the Clariion disk storage product lines.

- It leveraged open-source tools early.  The default m88k compiler installed with the system is GNU C 2.xx.

- It was among the earliest of operating systems to support NUMA aware affinity on MP versions of the MC88110. (IRIX, Solaris, BSD, Linux, and Windows support all came much later).

- Many others.

It does have it's quirks.  However I get the overall impression the folks working at DG were on their game and were a leader in the industry in many areas.  It is unfortunate a) the fate of the Motorola 88K was tied to Data General's place in the UNIX world, and b) by the time they migrated to IA86, enterprise business was more interested in Microsoft NT & SQL server or Linux than an expensive vendor's UNIX port.

That being said, I don't see DG/UX mentioned much in UNIX history.  In fact, I am researching an exhibit I'm putting together for the Vintage Computer Festival Southeast 7.0, and DG/UX isn't mentioned on any of the 'UNIX Family Tree' diagrams I can find so far.   It doesn't even make Wikipedia's 'UNIX Variants' page.  It's own Wikipedia page is also rather sparse.  Like John Snow in season 1, there is a junk of missing and plot impacting history here - centered around the people involved.

To a lesser degree, IRIX is also a red-headed step-child.  It's omitted from half the lists I can find.  It just seems the importance, even if it's an importance by being the 'first' rather than # of users, of these ports are pretty significant.

Just curious of others' thoughts.  And I wondering if anyone has first-hand knowledge of Data General's efforts or knows of others that can illuminate the shadows of what I'm discovering is a pretty exciting corner of the UNIX world.

Thanks,

-Alan H.