Initially I have decided to run the MUD on a microPDP-11/73 running BSD 2.11 Unix.

The chassis was fitted with a 4MB memory card, a third party eight channel DZV-11, a ethernet card and a CMD CQD-220 SCSI controller with a 18GB SCSI disk in an external case.

To get BSD onto the disk, I hooked it up to a PC running simh and prepared a suitable disk image.

One problem I encountered was that the standard MSCP driver wasn’t fully compatible with the CMD CQD-220 controller. To resolve this it is necessary to compile a patched boot block. This can be found here:  rauboot.s (original site).

To install, I fired up the disk image I was planning on using in SIMH and performed the following steps:

• cd /usr/src/sys/mdec/
• mv rauboot.s rauboot.s.orig
• vi rauboot.s
• i (For insert)
• pasted in above copy of rauboot.s
• after the paste completed, ESC :wq!  (write and quite)
• make    (rebuilds the mdec files)
• cp rauboot /mdec
• dd if=/mdec/rauboot of=/rra0a count=1

Once the disk image was prepared and working, the SCSI disk was hooked up to the SIMH box (running under linux) and the ‘dd’ command used to copy the disk image onto the disk.

Having done that, the disk was reconnected to the PDP and booted up into BSD 2.11. The ethernet was connected up to my office network (via a AUI transceiver). The /etc/netstart and /etc/hosts files were tweaked to assign the box an IP, subnet and gateway on the local network and /etc/inetd.conf modified to enable the FTP server. The PDP was then rebooted into multiuser mode and the network confirmed to be workin