> 1.  Is it really necessary to have installation *floppies* available?

No.  Merely convenient in many cases.

> Can I assume that if I can boot from CD-ROM I can also upgrade that
> way?

Probably, though of course I can't say definitely without trying it.

> 2.  Just how much of 2.0 do I have to get installed to have a working
> system?   Leaving aside anything that involves compilation, can I
> assume backward compatibility for vi, groff, X and so forth

Mostly, yes.  2.0_RC4 broke binary compatability with at least some
1.6.x executables that used nested functions.  A brief test I just did
indicates that 2.0 breaks binary compatability with 1.6 executables
similarly.

None of the stock OS programs use nested functions as far as I know;
they are a gccism, so code that needs to be portable to non-gcc
compilers can't use them (unless other compilers also support them - I
know of none that do).

> 3.  The documentation mentions that boot blocks will be rewritten, so
> I should back up anything that matters.

That is actually good advice before any upgrade, and it's more out of
paranoia - you probably will have no problem, but if something goes
wrong you can easily end up with a totally roached disk requiring
pretty severe groveling by a wizard to put back together again by any
means other than "wipe and restore from backups".

> Well, I do have a spare 20 Gig fdisk partition on the hard disk on
> one of these machines.   Can someone point me to how I go about
> setting up a NetBSD ffs on a different fdisk partition from the
> current one?   Not something I've ever had to do before...

Just put that part of the disk info a partition in the disklabel(8)
sense and use it.  Nothing actually _requires_ that all other
partitions fall within the NetBSD MBR (fdisk) partition.

> 4.  Is 2.0 going to want to alter the overall layout of my disk

In my experience, provided you do "upgrade" in sysinst, no.
Remembering a recent thread, this may not be true if you have
overlapping partitions.  disklabel output is singularly unhelpful in
this regard (guess why I wrote bsdlabel!); a quick eyeball of the
partition table you posted makes me think you don't have any problem,
but I didn't check that all the numbers were exactly right, just that
they were about right in the first few digits.

> (from the label:
> 16 partitions:
> )   (and BTW why does it say 16 partitions? I've always wondered...)

It's saying that in addition to wd0 through wd0h you can actually go as
high as wd0p (16 partitions = a through p).

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