Concurrent Program failed with ORACLE error 20100 in FDPSTP

FND_FILE creation failed.

In the concurrent program log file, we see below message.

ORACLE error 20100 in FDPSTP 
 Cause: FDPSTP failed due to ORA-20100: ORA-20100: File o2710130.tmp creation failed. File could not be opened or operated on as requested. 
 Action: Make sure the directory - /applptmp - is a valid directory with write permiss 


Checks for this error:

Option - 1:  Check your applptmp variable

applmgr@oracledemo ~
EBS: echo $APPLPTMP
/applptmp
applmgr@oracledemo ~
EBS:

Option - 2: Go to the applptmp directory and try to create or modify a file with applmgr.

applmgr@oracledemo ~
EBS: touch file
applmgr@oracledemo ~
EBS:

I'm able to create a file, so no issue with this.

Option - 3: Check utl_file_dir parameter in the database.

SQL> show parameter utl_file_dir

NAME                                 TYPE        VALUE
------------------------------------ ----------- ------------------------------
utl_file_dir                         string      /applptmp

This variable is pointing to right directory.


Option - 4: Create a test file using FND_FILE.

SQL> exec FND_FILE.PUT_LINE(FND_FILE.LOG, 'THIS IS A TEST');
BEGIN FND_FILE.PUT_LINE(FND_FILE.LOG, 'THIS IS A TEST'); END;

*
ERROR at line 1:
ORA-20100: ORA-20100: File o2711023.tmp creation failed.
File could not be opened or operated on as requested.
Action: Make sure the directory - /applptmp - is a valid directory with write
permissions and is accessible from the database server node for write
operations. This
ORA-06512: at "APPS.FND_FILE", line 319
ORA-06512: at "APPS.FND_FILE", line 364
ORA-06512: at "APPS.FND_FILE", line 421
ORA-06512: at line 1

This has failed and it written the error message clearly, /applptmp is a valid directory with write permissions and is accessible from the database server node for write.

About our environment, we have database on one server and application on another server.  On verification, somehow /applptmp is mounted on AppTier but not on DBTier, hence concurrent requests are failing.  Once we mounted the /applptmp on DBTier all requests got completed successfully.

SQL>exec FND_FILE.PUT_LINE(FND_FILE.LOG, 'THIS IS A TEST');

PL/SQL procedure successfully completed.