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2.11BSD on the RA81

Multi-user 2.11BSD Unix on an emulated UDA50 MSCP disk, with DELQA Ethernet that attaches as qe0. The kernel is the QBONETS build, carrying the QBus DELQA driver and the TS11 tape driver.

BusQBUS · QBone
NeedsA J-11 PDP-11 — 11/53, 11/73, 11/83, 11/93 — for the split I/D space the kernel needs, with at least 1 MB of memory.
Guest2.11BSD
CardsUDA50 · RA81 · DELQA
Download35 MB
Added2026-08-31
MaintainerQUniLator project — contact

Why it exists

A complete timesharing Unix that boots in under a minute and exercises the disk, the Ethernet and the serial console at once — the machine to hand somebody who wants to see a QUniLator do real work.

Using it

  • Switch the machine on and boot DU0 from the bootstrap prompt.
  • At the bare ':' prompt, press return: the system comes up single-user at a '#' shell.
  • Press Ctrl-D at the single-user shell to go multi-user; log in as root, which has no password.
  • /etc/netstart brings up qe0; edit it and /etc/hosts for your LAN.
  • Halt with /sbin/halt from single-user before switching off, so the filesystems stay clean.

Known problems

  • A dirty shutdown costs a long fsck on the next boot; the console sits quiet while it runs.

Links

Getting it onto a board

The board imports this itself once it subscribes to the catalogue — it fetches, verifies the checksum and imports, which is the route to prefer for a bundle this size.

To download it by hand and use the import dialog instead:

sha256 54114369570ac9ee69c58cf55cfa8e15ba0bda13f1afb672f8e36c1eca977131