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Server: FreeBSD 9.2-RC1, ZFS
Client: FreeBSD 9.0-RELEASE-p3
Filesystem is exported with "alldirs,maproot=root".

On the client, I can chown a file to any user but nobody.

client# touch foo
client# ls -l foo
-rw-r--r--  1 root  staff  0 Aug 20 11:18 foo
client# chown chris foo
client# ls -l foo
-rw-r--r--  1 chris  staff  0 Aug 20 11:18 foo
client# chown root foo
client# ls -l foo
-rw-r--r--  1 root  staff  0 Aug 20 11:18 foo
client# chown nobody foo
No name and/or group mapping for uid,gid:(65534,-1)
chown: foo: Operation not permitted

nobody exists on both client and server, with UID 65534 in both places. It looks like this is something to do with nfsv4's user mapping (nfsuserd), but I'm not finding good documentation on how that works. I've read hints that nobody is handled specially.

share|improve this question
what are your export options? – Petter H Aug 20 '13 at 17:31
looks like your user nobody has a group without mapping – kofemann Aug 21 '13 at 12:48
@PetterH, Filesystem is exported with "alldirs,maproot=root". – Chris Jones Aug 21 '13 at 18:47
@tigran, I think gid is -1 because it's not trying to change the group ownership. At any rate, the mapping is the same on both machines: uid=65534(nobody) gid=65534(nobody) groups=65534(nobody) – Chris Jones Aug 21 '13 at 18:51

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