Questions and problems with NFS4

["J.A. Magallón" <jamagallon@ono.com>]

Hi all...

I'm beginning to move my boxen to use nfs4, and have some questions...

First of all, versions of my software: kernel 2.6.33.5, nfs-utils 1.2.2
(perhaps some of my doubts are solved in newer versions)

Questions:

- Is it mandatory to use a setup with a common root for exported filesystems ?
  In my setup I first did not use it, no fsid=0 root, and everything
  worked fine, just change the mount type in the clients. In fact, new
  nfs-utils just try first version 4 and you dont have to do anything.
  You loose the ability to use simple paths inside /export, for example, 
  and have to use full paths like in V3, but that is not so bad.
  Am I loosing something else wrt functionality ?

- If you have a common root, is it mandatory to mount it in the client ?

- If I setup a common root (say /export), and aoutomount some folders:
  
  /scratch/local
  /scratch/node/00
  /scratch/node/01
  ......
  /export/scratch -> /scratch/local (bind mount).

  /scratch/node/?? is automounted from node ??, in which it is its own
  /scratch/local. When I acess scratch for local node, it backs to a local
  mount and mounts the REAL /scratch, not /export/scratch.
  Any ideas ?

- AFAIK, with NFS4 the only needed daemons are nfsd and idmapd. And the
  only accesible port from the outside is 2049, for nfsd.
  I have tried to strip down my nfs server (-N 2 -N 3 -U),
  but rpcinfo still gives me:

annwn:~# rpcinfo -p localhost
   program vers proto   port  service
    100000    4   tcp    111  portmapper
    100000    3   tcp    111  portmapper
    100000    2   tcp    111  portmapper
    100000    4   udp    111  portmapper
    100000    3   udp    111  portmapper
    100000    2   udp    111  portmapper
    100024    1   udp  48461  status
    100024    1   tcp  37515  status
    100021    1   udp  38583  nlockmgr
    100021    3   udp  38583  nlockmgr
    100021    4   udp  38583  nlockmgr
    100021    1   tcp  37873  nlockmgr
    100021    3   tcp  37873  nlockmgr
    100021    4   tcp  37873  nlockmgr
    100003    4   tcp   2049  nfs
    100005    1   udp  45341  mountd
    100005    1   tcp  58639  mountd

  disabling portampper and mountd is just a matter of initscripts
  requirements, but how can I disable nlockmgr ? It isn't needed for
  NFS4, isn't it ? Nor portmapper nor mountd...

TIA

--
J.A. Magallon <jamagallon()ono!com>     \               Software is like sex:
                                         \         It's better when it's free