MacOS Extensions pack for the Apple Network Server v1.0

By now regular readers of this blog are quite familiar with my affection for the 1996 Apple Network Server, Apple's Unix-through-and-through $10,000+ server that only shipped with, and only officially ran, Harpoon, its unique superset of IBM AIX. An ANS 500, the lower tier of this dorm fridge-sized computer, was the first server I ever personally owned, a nearly-new hand-me-down after Steve Jobs convinced Gil Amelio to cancel the machine and the bookstore's vendor at the University I worked for wouldn't support it anymore. There are several fascinating features present in Harpoon that were never implemented in any other Apple product. Currently I have three, that original ANS 500, this ANS 700 here which I use for testing, and a battery-bombed EVT prototype (a so-called "Shiner ESB" that used to be at Netscape).

The ANS was strongly based on the Power Macintosh 9500 and Apple was known to have demonstrated the ANS with Mac OS during development, but this confused potential buyers, causing the ability to boot Mac OS to be stripped from production systems. While then-CTO Ellen Hancock claimed in 1997 a ROM swap would enable the ANS to boot Mac OS again and Windows NT, these ROMs were believed to be vapourware until a former Apple employee presented a working dump of both the preproduction ROM and the later ANS Mac OS ROM. A prototype Windows NT ROM also emerged from another former employee, though there are pieces missing and booting Windows NT natively on the ANS is still a work in progress (hopefully to be the subject of a future article).

It turned out I had one of the preproduction ROMs myself and didn't realize what it was. Because the later Mac OS ROM was apparently unfinished, it doesn't properly support the L2 cache and consequently runs substantially slower, and it can't boot AIX. The preproduction ROM does boot both operating systems and does support the cache. On the other hand, it doesn't support the on-board video or the front Fast Wide SCSI-2 controller, the on-board MACE Ethernet doesn't work, and after MacOS first boots, the next restart without zapping the PRAM will come up with a black screen.

The good news is, many of the issues with the preproduction ROM in Mac OS can be fixed or worked around in software. So I've fixed or worked around many of them in software: the MACE Ethernet is fixed, the on-board video is now supported, and the ANS can restart properly back into Mac OS. Plus, because it's the preproduction ROM, you can still boot AIX, thus preserving the entire historical reason for Shiner's existence. Here's the first cut of that software and how it was developed.