Sqlplus "/as sysoper " : ORA-01031

Hi ,

i have been facing an issue with oracle recently for which i am unable to find a solution

i am running Oracle 11.2.0.3 on a linux server

the remote_os_authent parameter is set to true and the oracle id belongs is included in the 'oper' group.

[oracle@gbrlon05lx236 ~]$ id

uid=1280(oracle) gid=308(oinstall) groups=308(oinstall),300(dba),301(oper),302(sapsys),303(sapinst),309(asmadmin),310(asmoper),311(asmdba)

SQL> show parameter remote_os_authent;

NAME TYPE VALUE

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

remote_os_authent boolean TRUE

However, sqlplus "/as sysoper" does not work and i get a ORA-01031

[oracle@hometest ~]$ sqlplus "/as sysoper"

SQL*Plus: Release 11.2.0.3.0 Production on Mon Mar 17 08:39:36 2014

ERROR:

ORA-01031: insufficient privileges .

Sqlplus "/as sysdba" connects without any issues at all.

[oracle@hometes ~]$ sqlplus "/as sysdba"

SQL*Plus: Release 11.2.0.3.0 Production on Mon Mar 17 08:53:03 2014

Connected to:

Oracle Database 11g Enterprise Edition Release 11.2.0.3.0 - 64bit Production

With the Partitioning, Real Application Clusters, OLAP, Data Mining

and Real Application Testing options.

Please can anyone advise on what could be the possible causes for the connection to fail when tried with sysoper privelege.