ORA-09925: Unable to create audit trail file SVR4 Error: 13: Permission denied login with /as sysdba

ORACLE 10G  and 11.2.0.3

Login with /as sysdba
ORA-09925: Unable to create audit trail file 
SVR4 Error: 13: Permission denied 


Problem:-  I have installed a 10g database with Oracle owner, group DBA and it is working fine with Oracle owner.

Again I have created a  new user USER1 and add it in DBA group and also in other group in which Oracle user exists to run same command as Oracle user .

But getting below error.

su - user1
password:-
-bash-3.2$ . oraenv
ORACLE_SID = [] ? orcl
-bash-3.2$ sqlplus

SQL*Plus: Release 10.2.0.4.0 - Production on Tue Dec 22 06:17:32 2015

Copyright (c) 1982, 2007, Oracle.  All Rights Reserved.

Enter user-name: /as sysdba
ERROR:
ORA-09925: Unable to create audit trail file
SVR4 Error: 13: Permission denied
Additional information: 9925
ORA-09925: Unable to create audit trail file
SVR4 Error: 13: Permission denied
Additional information: 9925

Solution:- 

1. Login with Oracle owner and change the file permission as mentioned below.

cd /u01/app/oracle/product/10.2/dbhome/bin/

$ls -lrth oracle

$-rwxr-x--x   1 oracle   oinstall    120M Jun 24  2015 oracle

$chmod 6751 oracle

$ls -lrth oracle

$-rwsr-s--x   1 oracle   oinstall    120M Jun 24  2015 oracle

2.Now login with user1

-bash-3.2$ . oraenv

ORACLE_SID = [user1] ? orcl

-bash-3.2$ sqlplus

SQL*Plus: Release 10.2.0.4.0 - Production on Tue Dec 22 07:04:21 2015

Copyright (c) 1982, 2007, Oracle.  All Rights Reserved.

Enter user-name: /as sysdba

Connected to:

Oracle Database 10g Enterprise Edition Release 10.2.0.4.0 - 64bit Production

With the Partitioning, OLAP, Data Mining and Real Application Testing options

SQL> select name,open_mode from V$database;

NAME      OPEN_MODE

--------- ----------

ORCL     READ WRITE