> invalid partition table
> no operating system.

I too installed RedHat and got a similar problem.
It seems that the redhat boot selector (lilo) ocuppies
a part of the disk which netbsd installer does not touch.

If you like to boot all the OSes from HDD, you may have to make lilo the booter,
but I didn't take that way because I didn't need linux at all so that I deinstall
linux.

My suggestion is that you use a boot floppy for linux and an HDD booter for netbsd.

- ----------------------
K. Takai (kazuhiko_takai@anet.ne.jp)