Ok, extracted from the tcpdump:
13:27:17.786122 scorpius.mpimf-heidelberg.mpg.de.2007650305 > tera.mpimf-heidelberg.mpg.de.nfs: 124 getattr fh 7952,133807/0
13:27:17.786730 tera.mpimf-heidelberg.mpg.de.nfs > scorpius.mpimf-heidelberg.mpg.de.2007650305: reply ERR 20 getattr [|nfs]
13:27:17.787138 scorpius.mpimf-heidelberg.mpg.de.2007650306 > tera.mpimf-heidelberg.mpg.de.nfs: 96 fsinfo [|nfs]
13:27:17.787627 tera.mpimf-heidelberg.mpg.de.nfs > scorpius.mpimf-heidelberg.mpg.de.2007650306: reply ERR 20 fsinfo [|nfs]
13:27:17.787860 scorpius.mpimf-heidelberg.mpg.de.2007650307 > tera.mpimf-heidelberg.mpg.de.nfs: 96 fsstat fh 7952,133807/0
13:27:17.788363 tera.mpimf-heidelberg.mpg.de.nfs > scorpius.mpimf-heidelberg.mpg.de.2007650307: reply ERR 20 fsstat [|nfs]

So the server returns an error for the NFS requests; if I'm not mistaken
error 20 is NFSERR_NOTDIR (from nfsproto.h). are you sure tera:/users is
a directory, and not something else (a symlink to some other place) ?

Maybe you can try to force NFSv2 (mount_nfs -2 or mount -o -2) ?

--
Manuel Bouyer <bouyer@antioche.eu.org>
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