>I've just tried twice to install NetBSD in a spare partition on a disk
>currently containing FreeBSD.  Both times, the installation of NetBSD
>clobbered FreeBSD (at least to the extent that it would no longer boot -
>I don't believe it had actually overwritten the contents of FreeBSD
>partition, since I was careful in specifying cylinder counts, etc).
>
>The FreeBSD partition was in the 2nd half of the disk, and I was trying to
>install NetBSD (1.2G) in the first half.  I also had the os-bs boot
>selector installed in sector 0 of the disk.  My feeling is that installing
>NetBSD is clobbering the FreeBSD bootblocks, or something like that.

>Thinking about it now, I don't think I've ever installed a dual boot
>NetBSD system (NetBSD and DOS) where the NetBSD partition was the first
>on the disk (previously DOS has always been first, and I've noticed that
>typically DOS partitions start on the 2nd track).

hi Duncan,

I have never, ever gotten this to work, and (as you know:) I'm pretty
persistent with such things.  I'e installed NetBSD onto five machines
that already had Linux on them.  I always pre-prepared an MBR
partition and marke it as 386BSD before beginning the install.  The
NetBSD installation clobbered the bootblocks every single time.  Other
people say they haven't been able to reproduce this.

Did you get a warning about `Erase the previous contents of the disk'
from disklabel?  It *really* means that; it's about to overwrite the
MBR with its own DOS bootrecord, tossing away any MBR partitions you
might have. 

UTSLing, I *think* maybe the right way to do this is to write the
label and bootblocks to the C partition, not the D partition.  Which
did you use?