NFSv4 permissions issues

[Rick Macklem]

From: "Joe Auty" <joe at netmusician.org>
> To: freebsd-fs at freebsd.org
> Sent: Wednesday, July 28, 2010 3:31:25 AM
> Subject: NFSv4 permissions issues
> 
> Hello,
> 
> In FreeBSD 8.1 when mounting an NFSv4 share (hosted by Solaris 10/ZFS) I
> cannot create or alter any files on this share nor any other share
> mounted from this same ZFS server. When I try to do so I get permission
> denied error messages. This same share does not give me any problems
> when mounted with identical mount options except for specifying NFSv3
> rather than NFSv4... i.e.
> 
> mount -t nfs -o rw,tcp,intr,noatime,nfsv3 myip:/path /path
> 
> works fine, and:
> 
> mount -t nfs -o rw,tcp,intr,noatime,nfsv4 myip:/path /path
> 
> exhibits the above problems...
> 
> 
> Any idea why this is so and what I ought to do to test using NFSv4 on
> this machine?

1 - look to see if the username/groupname mappings are working. (NFSv4
uses name and not#s.)
    - just do an "ls -lg" on some NFSv4 mounted dir. to see if they
      look ok. (lotsa "nobdy"'s --> busted) If it's busted, look at
      the setup of nfsuserd and the "domain" specified, which is
      usually the domain part of the host's name, but can be overridden
      by a flag option on nfsuserd and in a config file on Solaris10.

2 - Make sure you user/group names and uid/gid numbers are consistent
      between client and server. NFSv4 always specifies the groupname
      of a newly created file object, so those groups/gids must be
      correct.

If the above doesn't resolve it, look at a snoop trace for the failed
access and see what the user/group names (and uid/gid #s in the RPC
header) look like.

This is most likely something related to the user/group name and
number mapping, rick