The tiny bits of OpenBSD that are completely specific to the Sun3 port are basically the same as their NetBSD counterparts but with some additions. The major changes are:
Snapshots of the kernel and diskless bootstrap loader are available. If you want to use OpenBSD/sun3 get an Amiga (or any other m68k OpenBSD) snapshot and the Sun3 GENERIC kernel and diskless bootstrap loader then if you don't know how to set up a diskless box read the diskless(8) manpage. Use the MAKEDEV from src/etc.sun3. Once you have booted the Sun3 diskless you should be able to "cd /usr/src; make obj; make build" to get a native OpenBSD/Sun3. Before doing this kernel instrumentation ("ps", "netstat", etc.) will not work.
The diskless configuration is prone to instability. If many processes coredump during multi-user startup, hit <L1-A> and from the ``<'' prompt use ``b le()bsd'' to reboot again. It usually works on the second try for me. With a local harddisk I have not noticed this behaviour yet.
You can use cvs to get The X Window System. I have been told that my patches for OpenBSD/sun3 were integrated in it but have not had time to test yet. Additionally, a patch kit for XFree86 3.2 is available in the snapshot directory. Look for xfree86-3.2-sun3-patch-kit-1.gz.
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