Backup to remote location fails with ORA-19504 andORA-27054

Error Description
I mounted remote location jupiter:/export/home/oracle on my local server as /export/home/oracle/remote and then I wanted to take RMAN backup on the mapped drive but it fails with ORA-19504: and ORA-27054:.
RMAN> backup format '/export/home/oracle/remote/%U' datafile 4;

Starting backup at 13-OCT-08
using target database control file instead of recovery catalog
allocated channel: ORA_DISK_1
channel ORA_DISK_1: sid=136 devtype=DISK
channel ORA_DISK_1: starting full datafile backupset
channel ORA_DISK_1: specifying datafile(s) in backupset
input datafile fno=00004 name=/oradata1/shaik/SHAIK/users01.dbf
channel ORA_DISK_1: starting piece 1 at 13-OCT-08
RMAN-00571: ===========================================================
RMAN-00569: =============== ERROR MESSAGE STACK FOLLOWS ===============
RMAN-00571: ===========================================================
RMAN-03009: failure of backup command on ORA_DISK_1 channel at 10/13/2008 04:02:40
ORA-19504: failed to create file "/export/home/oracle/remote/03jt0tav_1_1"
ORA-27054: NFS file system where the file is created or resides is not mounted with correct options
Additional information: 2
Cause of the Problem
From Oracle 10.2g , Oracle checks by which options NFS mount is mounted on local filesystem. This checking is done to ensure that no corruption of the database can happen as incorrectly mounted NFS volumes can result in data corruption.

Generally the following checks are done on Solaris and AIX systems.

1) In order to check the mount option whether mount table can be read. Issue,
# cat /etc/mnttab

2) While NFS mount is "hard" option provided.
3) Whether the mount options include rsize>=32768 and wsize>=32768
4) If RAC environments, where NFS disks are supported, whether the "noac" mount option is used.

If above requirements are full and still above error appear then possibly oracle bug.
Solution of the Problem
Solution 1: Setting the mount option explicitly.
# mount -o rw,bg,hard,nointr,rsize=32768,wsize=32768,tcp,vers=3,timeo=600,actimeo=0 jupiter:/export/home/oracle /export/home/oracle/remote

The default rsize and wsize for NFS is 4096 Blocks

So if you have rsize=32k and wsize=32k then NFS would be able to read and write large datagram as
compared to deafult one.

TCP option will make sure that your client are getting the data or not

Hard & INTR - The program accessing a file on a NFS mounted file system will hang when the
server crashes. The process cannot be interrupted or killed unless you also specify intr. When
the NFS server is back online the program will continue undisturbed from where it was.

actimeo is for access timeout and it should be 0 .

After setting above parameters in NFS mount clause you will be able to take the backup
RMAN> backup format '/export/home/oracle/remote/%U' datafile 4;
And see it would be successful.

Solution 2: Set the Event 10298
SQL> alter system set event="10298 trace name context forever, level 32" scope=spfile;
System altered.

Now restart server and take backup.
SQL> startup force
ORACLE instance started.

Total System Global Area 234881024 bytes
Fixed Size 2019800 bytes
Variable Size 125832744 bytes
Database Buffers 100663296 bytes
Redo Buffers 6365184 bytes
Database mounted.
Database opened.

SQL> show parameter event

NAME TYPE VALUE
------------------------------------ ----------- ------------------------------
event string 10298 trace name context forev
er, level 32

RMAN> backup format '/export/home/oracle/remote/%U' datafile 4;

Starting backup at 13-OCT-08
using target database control file instead of recovery catalog
allocated channel: ORA_DISK_1
channel ORA_DISK_1: sid=135 devtype=DISK
channel ORA_DISK_1: starting full datafile backupset
channel ORA_DISK_1: specifying datafile(s) in backupset
input datafile fno=00004 name=/oradata2/shaikdba/shaikdba/shaik/users01.dbf
channel ORA_DISK_1: starting piece 1 at 13-OCT-08
channel ORA_DISK_1: finished piece 1 at 13-OCT-08
piece handle=/export/home/oracle/remote/08jt0voi_1_1 tag=TAG20081013T044402 comment=NONE
channel ORA_DISK_1: backup set complete, elapsed time: 00:00:01
Finished backup at 13-OCT-08

Solution 3: If Oracle bug
If still fails then possibly an oracle bug for Oracle 10.2.0.1. In order to solve bug apply 5146667 one off patch for 10.2.0.1.