(OS:  Linux 2.6.18-128.1.6.el5 #1 SMP Tue Mar 24 12:05:57 EDT 2009 x86_64 x86_64 x86_64 GNU/Linux)

(DB:   Oracle Enterprise 10.2.0.4 )

#>/ora01/EXPORTS[PRODDB] expdp content=metadata_only schemas=scott dumpfile=scott.dmp logfile=scott.log directory=expdir

Export: Release 10.2.0.4.0 - 64bit Production on Wednesday, 06 January, 2010 14:21:22

Copyright (c) 2003, 2007, Oracle.  All rights reserved.

Username: / as sysdba

Connected to: Oracle Database 10g Enterprise Edition Release 10.2.0.4.0 - 64bit Production
With the Partitioning, Data Mining and Real Application Testing options
ORA-39001: invalid argument value
ORA-39000: bad dump file specification
ORA-31641: unable to create dump file "/ora01/EXPORTS/scott.dmp"
ORA-27054: NFS file system where the file is created or resides is not mounted with correct options
Additional information: 3

At first I couldn't figure out the exact message and why because I was able to read write successfully as the oracle account to /ora01/EXPORT directory.  No issues.  But i realized that oracle checks the mount permisssions now.  I had the unix SA update the mtab file show that the word "hard" is placed correctly and update the mtab file.    Here is the before and after:

BEFORE:

cat /etc/mtab

host:/vol/dbdump_col/proddb_prd1 /ora01 nfs rw,nfsvers=3,tcp,intr,rsize=4096,wsize=4096,addr=192.168.1.2 0 0

AFTER:

cat /etc/mtab

host:/vol/dbdump_col/proddb_prd1 /ora01 nfs rw,bg,hard,rsize=32768,wsize=32768,nfsvers=3,nointr,timeo=600,proto=tcp,addr=192.168.1.2 0 0

 Hope this helps.

Thanks,