Excerpts from netbsd: 28-Jul-97 gaaah again! bootinstall tr.. Erik
Rungi@openface.ca (1866*)

> Ok so when table slot 3 is empty, I can boot off of the HD by throwing the
> install floppy in and typing "BOOT wd0a:netbsd".  However, if I set this
> slot 3 partition ID to 165 (hex A5) which corresponds to NetBSD partition
> type as the manpage suggests, I can no longer boot the HD kernel off the
> floppy.

If you can boot from the harddisk, you obviously have a NetBSD
filesystem on it. I guess you have installed it at the beginning of the
disk. The boot code assumes exactly this if there is no NetBSD entry
in the BIOS partition table.
When you try the NetBSD partition ID, this entry seems to point to
another location.

> I tried
> to install the old boot loader code and get OS-BS to recognize that, and
> this worked fined except that the old bootloader couldn't get the new
> kernel going.

There was no change in the kernel calling parameters, there must
be another reason.

> The newish looking "installboot" command seems to make
> sense from the manpage, but doesn't actually do anything as far as getting
> me closer to having a booting system.

You should be more specific.

As I said, the BIOS partition table entries seem not to match
reality. You should solve this first.
Be sure to use the correct drive geometry as used by the BIOS
(perhaps use the DOS "pfdisk" program) and to have 1 free track
at the beginning of the disk for the boot selector.

best regards
Matthias