Oviwan’s Weblog

source: http://www.oracle.com/technology/deploy/performance/pdf/directnfsclient_11gr1_twp.pdf

I have tested the Oracle NFS Driver on Oracle Enterprise Linux 5.1 with Oracle 11.1.0.7

Instead of using the Kernel NFS Driver, Oracle 11g provides its own Direct NFS driver. Hence Oracle will optimize the I/O path between Oracle and the NFS server.

The following is the order where Oracle searchs for NFS exports.

1. $ORACLE_HOME/dbs/oranfstab
2. /etc/oranfstab
3. /etc/mtab (content of mounted /etc/fstab)

So you have just to configure your /etc/fstab,  with no special parameter as mentioned in metalink#359515.1 , as follow:

filername:/vol/nfs_data01/q_nfs_data01  /nfs/SID/data1   nfs

mount -a

Then you have to link some libraries in your $ORACLE_HOME

cd $ORACLE_HOME/lib
mv libodm11.so libodm11.so_stub
ln -s libnfsodm11.so libodm11.so

Now you can start your Oracle Instance and check the alertlog file for this line:

Oracle instance running with ODM: Oracle Direct NFS ODM Library Version 2.0

Hence the Driver of Oracle is used for NFS.

There are also some Views to check the stats and the current nfs exports you are using:

SQL> SELECT svrname, dirname FROM v$dnfs_servers;

SVRNAME    DIRNAME
---------------
filername  /vol/nfs_data01/q_nfs_data01

Some other views:

v$dnfs_servers
v$dnfs_files
v$dnfs_channels
v$dnfs_stats