Dell UNIX Lives Again!

(please note that this is a guest post from Antoni Sawicki)

Dell UNIX is so ultra rare among rare Unix species that it doesn’t even have a Wikipedia entry. I have been hunting this elusive but important piece of computer history for well over 15 years now. Fortunately thanks to Charles H. Sauer and his excellent blog post I was finally able to lay my hands on disk and tape images and the restoration process begun.

The install tape

The system can be installed from either a tape or network server (presumably NFS). Unfortunately no virtualization software can emulate a tape drive. Hopes for a network install are even slimmer since the required network support floppy disk has been lost and chances of suitable Ethernet driver working in Bochs or Qemu are equal to that of finding the lost floppy disk.

I have decided to try a hard disk image from a readily pre-installed system. The original Dell 486 workstation had a 1GB SCSI hard disk. Unfortunately neither Dell UNIX supports LBA mode nor Qemu/Bochs support the Adaptec 154x controller required by the OS.

As all normal install options have been exhausted, the only option left was to use a second hard disk image as source of cpio archive files. Booting from the two install floppies and attaching two disk images was a snap. The next step was to inject the tape “file” in to a right place on the disk, so it can be read by cpio command. A hard disk in Dell UNIX is pretty much unusable without a valid SysV partition and VTOC. Fortunately dellsetup command does it all for you. Once VTOC was put in place I’ve attached the transfer disk image as a loopback device in my host OS. In couple of iterations I was able to aim the host os dd if=file1 of=/dev/loop0 bs=512 seek=offset at the right place, which you work out using prtvtoc /dev/rdsk/1s0 command. Then cpio -ict < /dev/dsk/1s1 was able to list contents of the emulated tape… with errors…

In my infinite wisdom, for some unknown reason I’ve assumed that LBA addressing is required above 540MB. So to be on a safe side I have made the hard disk images 512 MB. What a mistake it was! I have lost several hours trying to figure out cpio header errors coming from the disk… By pure coincidence, while the tape archive was installing (with errors) I was researching for this very blog article and found that LBA starts at 504 MB… Recreating the hard disk images just few MB smaller took all tape and prior boot problems away!

Once the cpio archive was extracted I have made few final touches taken from the original tape install script. After a reboot Dell UNIX booted perfectly. You can experience this by using the firstboot image file. The final part of installation was injecting the second tape file containing System V PKG file to the transfer disk image and running pkgadd -d /dev/dsk/1s1. This is what’s included on allsoft.img.

Dell Unix at First Boot

Some final notes on running the OS:

  • To enable mouse to work:
    • Qemu just add “-chardev msmouse,id=msmouse -device isa-serial,chardev=msmouse” to the launch arguments.
    • Bochs add to the config file:
      mouse: type=serial, enabled=1      
      com1: enabled=1, mode=mouse
      then you have to kill mousemgr process and prevent from starting by deleting /etc/rc2.d/S25mse
      then edit /usr/lib/X11/Xconfig:
      disable Xqueue      
      enable Microsoft Mouse
  • To enable keyboard to work correctly in VirtualBOX start with Num Lock OFF.
  • You can use qemu-img utility to convert the image to VMware vmdk to use in VirtualBox.
  • To run X window type startx

X11 and all its glory

  • To attach it to internet use SLIP as there is no working Ethernet driver.  Contrary to most UNIXen of the time, the command is not slattach, but rather slipattach.  Thankfully it does work the same way.  I have found that running Dell Unix with VirtualBOX, along with Windows NT 4.0 I was able to connect into the Dell Unix VM, and get network access.  Just set the two VM’s up for a named pipe (\\.\pipe\dellunix) and make one of them a server, and start that VM 1st.  The steps to prepare Windows NT have been outlined before.

Telnet via SLIP

Legal disclaimer: Dell UNIX is a commercial software and should not be distributed without manufacturers permission. However as the operating system has been dead for 20 years and with a long tradition from Unix Heritage Society and Bitsavers I’m publishing this in good faith under abandonware category. If Dell or any other copyright holder wishes this software removed, please let me know.

Attached are:

  • firstboot image
  • all (pkg) software installed
  • setup instructions if you wish to install from scratch.


You may also be interested in my post about a sister System V operating system – Interactive UNIX:

Back to 386 BSD

Well gunkies is getting a little more life to it, and Dugo contributed this install guide for 386 BSD. Along the way I installed it again with floppy images, and I hit the same fault again:

/386bsd: wd0a: overlaps open partition (b)

However this time I noticed that if you keep on rebooting, it’ll actually stop complaining and work!

So not only was I able to recover from a crash after trying to install the source code, but I was able to complete the install, and install the patchkits! What this has resulted in, is that Qemu can now run 386BSD!!! And it’s significantly faster then Bochs. Not to mention you gain the whole SLiRP / Usermode networking.

So far I’ve tested this with Qemu-0.11.0 just fine. I’m not sure about other levels… so it’s another YMMV.

So now I’ve been able to not only rebuild the kernel & world, but the following programs:

gzip 1.2.4
unzip 5.52
irc II-4.4
lynx 2.8.2

Oh yeah, and another f2c build, and yes it’ll run Dungeon!

So for the few people interested in some BSD history, as this is the ‘first’ Net/2 derived freely available release in a qemu format right here (sorry, link removed, if you want it install this instead).

Just uncompress the qcow2 file (sorry it’ll blow out to 500MB), then run Qemu something like this:

i386-softmmu/qemu.exe -L pc-bios -hda bsd386.qcow2 -M isapc -net nic -net user -no-reboot -m 256

And with any luck, you’ll find the VM booting, and all set and ready to roll. If it comes up in single user-mode, just close Qemu & fire it up again..

I’ll probably put together a windows install package for this later, but for now I figure I’ll unleash some 386BSD onto the world.


(please note that this is a guest post from Tenox)


I’ve been hunting for a complete INTERACTIVE UNIX System for past 12 years or so. While I had the basic set of it for a good bit of time, no one seem to have have the real stuff – Looking Glass graphical environment. In November I got my hands on a box containing a massive set of 50 5.25″ floppy disks. There is the first time you can look on the GUI:

Through the looking glass..

The fun really begins with this page:
As of 2010 it has an Oracle logo and tells about an operating system by Sun Microsystems (now Oracle) for which support ended just 4 years earlier. In reality the OS was rather little known to the general population.


First introduced by Kodak in 1985 was mostly used for specialized applications. Later Sun bought it to help porting Solaris to x86 platform. Enough of history.

Version 3.0 presented here unfortunately only works on Bochs 2.4.2. There are some issues with the IDE/ATA controller that make it boot up only every second time while clicking on reset button. Version 4.x has issues partitioning disks under VMware but I’m sure this can be worked around.

The installation is straight forward once you have correct settings for the emulator (bochsrc.bxrc included). With this blog post included is a fully working, ready installed system, just double click run.bat. If it hangs, click on the Reset button. The root password is root. To shutdown the system cleanly type “init 0”, but this must be done from the text mode console.

I’ve spent a bit of time trying to bring it to a higher resolution but so far I only managed 800×600. You have a number of graphics drivers available under the “xconfig” program. One of the most curious features of Looking Glass are the icons. Some of them ROTFLMAO.


The next task will be to install and configure networking. But this is for another post.


Unfortunately the floppy disk is all but unreadable.

386BSD & Bochs


386BSD on Bochs

While checking around on wikipedia for something related to 4.2BSD, I found out that bochs 2.4 can run 386BSD!

Now the significance of 386BSD is that it was the real first time that BSD had been given to the masses, in that it *could* run on commodity hardware (read 386’s!), come with full source code and be free. It is no wonder that the initial 0.0 release had well over 100,000 downloads!

It is getting harder and harder to track down a download source for 386BSD as it too was swept up in the great lawsuit of AT&T vs BSDI/CSRG although it was never named in the suit. Not to mention it was quickly superseded by the FreeBSD & NetBSD projects. It is very unstable in the 0.1 release, there is clearly some issues with it’s “install” program with regards to allocating swap space, and in general with the OS’s swapping routines. Also because of the overlap any attempt to install on a disk larger then 100MB results in a corrupted file system that will no longer boot after the eventual file corruption. It’s quite sad, but if you search the news group at the time, there was all kinds of issues with the install process, and with it’s stability.

The installation process does involve quite a bit of floppy shuffling, and will almost result in lots of trial & error to get it going. While there is an install guide on the install disk, it isn’t worded into exactly how to do it. Needless to say the Free/Net BSD releases have improved on the install greatly.

On the other hand it sure is interesting to see a Net/2 BSD to see how far we have come, and how so much is the same.

You can find 386BSD on the mirror site

Just watch out that the install floppy (dist.fs) is only 1.2MB.. So be sure to alter your bochsrc file accordingly.

A minor update….

OS/2 1.3 on Bochs

OS/2 1.3 on Bochs

OS/2 1.3 does infact run under BOCHS. Here is the catch, like Xenix you currently must make an image of an existing installation, and point Bochs towards it.

Here is the flag that I used:
ata0-master: type=disk, path=”os2-1.3.img”, cylinders=919, heads=16, spt=17

Bochs will complain about the geometry not matching… Just hit the ignore button, and it boots up just fine.

Thanks to Geoff Shearer for trying, since I had figured it wouldn’t even work.

I promise, a quick tour of SLS Linux next time… Where the distro wars all started!