I'm a refugee from BSD/OS who's been running a couple of 1.6.2 systems
for several months in anticipation of moving to 2.0 as standard
(around a dozen machines) when it finally appeared.   But given the
inevitable delays, I'm a bit more committed to 1.6.2, i.e. I've done
some significant amounts of work with it, than I intended.

I have some queries about the upgrade process for which there may well
be a good RTFM answer, but from what I have seen in the documentation
I can only find a few paragraphs which are fine so far as they go
but...

1.  Is it really necessary to have installation *floppies* available?
I installed my 1.6.2 systems from CD-ROM ISO images, and actually
don't even have a floppy drive (or the scope to fit one) to one
machine.   Can I assume that if I can boot from CD-ROM I can also
upgrade that way?

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 (yes, I'm
an ageing Unix hacker), or should I really be seeing this as a fresh
installation necessarily?   It's just that I have work to do as well,
and ideally I don't want surprises.   Without experience of
undertaking previous upgrades, I'm wondering if I'm going to find I
have to reconfigure numerous things I rely on (sendmail, named,
NFS...)

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

4.  Is 2.0 going to want to alter the overall layout of my disk (from
the label:

16 partitions:
#        size    offset     fstype  [fsize bsize cpg/sgs]
 a:   2009889        63     4.2BSD   1024  8192    86   # (Cyl.    0*- 1993)
 b:   3934224   2009952       swap                      # (Cyl. 1994 - 5896)
 c:  40960017        63     unused      0     0         # (Cyl.    0*- 40634)
 d:  78140160         0     unused      0     0         # (Cyl.    0 - 77519)
 e:   9625392   5944176     4.2BSD   1024  8192    86   # (Cyl. 5897 - 15445)
 f:   9625392  15569568     4.2BSD   1024  8192    86   # (Cyl. 15446 - 24994)
 g:   1433376  25194960     unused      0     0         # (Cyl. 24995 - 26416)
 h:  14331744  26628336     4.2BSD   1024  8192    86   # (Cyl. 26417 - 40634)

)   (and BTW why does it say 16 partitions? I've always wondered...)

and from mount:

/dev/wd0a on / type ffs (NFS exported, local)
/dev/wd0e on /usr type ffs (NFS exported, local)
/dev/wd0f on /usr/local type ffs (NFS exported, local)
/dev/wd0h on /home type ffs (NFS exported, local)

My /usr/local contains only locally written stuff, BTW.

TIA