Human readable document on NFS server on FC16

[Bill Davidsen]

I had an NFS server motherboard go bad, and a quick replacement resulted 
in the drives coming up in all the wrong places, and no room to do a new 
install. I'm running at the moment off a USB boot to keep thinks going 
until I get an SSD so I can install there. A thumb drive on a USB 3.0 
port is not a bad substitute for an SSD short term.

Anyway, the issue is ID mapping from the server to the clients. The 
documentation is written using terms like
   "NFS4_user_object at REALM = local_user_object"
and while I have the more recent clients working, machines lacking the 
rpc.idmap (aka nfs-idmap) capability aren't working. Since I have to 
support the existing clients rather than having the ability to force 
sensible upgrades, and many of the clients just don't do idmap, two 
questions.

FIRST - is there a human readable document with examples which just show 
what client and server mods to /etc/idmapd.conf should be made such that 
joe at foo.demo.org gets access to the joe files on the server, and what 
the effect of those changes is are on the client and server sides. 
That's sort of medium critical, since I have that working. It's unclear 
if and how some of the terms map to OO languages.

SECOND - is there a way to get the server to provide NFS3 service for 
the machines which were put in service before the even was an NFS4? 
Other than running a whole different server? I see that it is supposed 
to happen if /proc/fs nsf* are unmounted, but that creates breakage. Is 
there something simple to make that happen?

All I need is some doc so I can be sure I've done things right, as 
opposed to hacked until they work.
-- 
Bill Davidsen <davidsen at tmr.com>
   "We have more to fear from the bungling of the incompetent than from
the machinations of the wicked."  - from Slashdot