MkLinux and the pimped-out Apple Workgroup Server 9150

Old Vintage Computing Research REWIND and PLAY Saturday, August 1, 2026

As is customary within the confines of the Floodgap lab, this project began with a simple, innocent goal: the restoration of a temperamental Apple Workgroup Server (WGS) 9150. This particular machine is the "odd man out" of the Workgroup Server family and serves as the elder relative to the more famous Apple Network Server.

The Evolution of the Apple Server

Before the arrival of the sui generis IBM AIX-powered Apple Network Server (a personal favorite here at Floodgap), Apple attempted the WGS line. These were essentially high-specification Macintosh rebadges, bundled with specialized server software and beefed-up hardware options.

While power users had been hacking together desktop Macs to act as makeshift servers for years, the WGS line represented Apple's first official foray into the server market. The initial generation was even marketed with A/UX, Apple's proprietary hybrid of System V UNIX.

The Shift to Linux

Unfortunately, A/UX failed to survive the transition from 68K processors to PowerPC in 1994. However, by 1996, Apple introduced a new alternative: MkLinux, which utilized the Mach microkernel.

Although the 9150 was discontinued before MkLinux arrived, the machine is essentially just a massive NuBus-based Power Mac. By upgrading the CPU, expanding the RAM, and adding various video cards, the goal is to create a "best of both worlds" machine:

• Classic MacOS for nostalgia and legacy support.
• MkLinux for the Unix experience.

[!NOTE] A warning to those handling these machines: the aging plastics are brittle and do not want to stay in one piece.

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Rebuilding the "Green Giant"

To understand where we are, we have to look at where Apple went wrong. While I've previously discussed how the Apple Network Server ended up running IBM AIX, we haven't explored why CEO John Sculley pushed for a server line in the first place, nor the relationship between the WGS and the standard Mac line.

The "Macintosh Office" Ambition

Apple's lack of experience with "big iron" (mainframe/enterprise hardware) meant their server strategy was born from the ashes of the failed Macintosh Office concept. In January 1985, Apple launched a suite of hardware intended to revolutionize the workplace:

1. AppleTalk Personal Network (later known as LocalTalk): Multidrop serial links for device communication.
2. The LaserWriter: A high-end shared printer.
3. The Macintosh XL: A revamped Lisa 2/10 with increased storage and RAM, integrated into the Mac ecosystem.

Financials and Projections

Steve Jobs (then Chairman and VP of the Mac division) predicted 10,000 of these networks would be active by year's end. The pricing was a strategic gamble:

The Macintosh XL was actually intended to be a permanent fixture stopgap—a way to clear out Lisa hardware while Apple developed the true centerpiece: The "Big Mac."

The Legend of the "Big Mac"

The "Big Mac" was envisioned as a high-end workstation or file server running Unix, potentially with a Macintosh GUI layered on top. Internally, it was dubbed the "3M" project because of its target specifications:

$\text{3M} = \begin{cases} \text{1 Megapixel display} \\ \text{1 Megabyte of memory} \\ \text{1 Million instructions per second (via 68020)} \end{cases}$

The Collapse of a Vision

The plan unraveled due to unexpected success and internal strife. The Macintosh XL sold so rapidly that Apple exhausted its inventory in three months—far faster than the predicted eighteen.

"Apple's strategy may have been too good," mused InfoWorld.

Simultaneously, the LaserWriter suffered massive manufacturing delays, with only 2,500 units shipping by June. This vacuum was filled by third parties like 3Com and Centram (TOPS).

By May 1986, the board had seen enough of Steve Jobs' management style. He was sidelined in May and gone by September. Because the "Big Mac" was so closely tied to Jobs, it became a political liability. New product manager Jean-Louis Gassée dismissed the project as a "toy" and pivoted toward the Milwaukee project, which became the Macintosh II.

The Aftermath

This volatility damaged Apple's reputation with corporate clients. To repair this, Sculley made a public pledge during the Macintosh Plus launch:

"I know the real commitment from business customers must be earned by meeting customer needs, by living up to expectations and by keeping promises. We intend to do all of that."

Despite the failure of the Big Mac, the desire for a powerful, networked Apple machine persisted, eventually leading us to the Workgroup Server 9150.

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Project Checklist: Pimping the 9150

• Stabilize brittle chassis plastics.
• Install high-capacity RAM modules.
• Upgrade to the fastest compatible CPU.
• Configure NuBus video cards.
• Install and boot MkLinux.
• Verify Classic MacOS stability.

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