How to find OSDBA OSASM OSOPER group

How to find OSDBA or OSOPER or OSASM Group

What is OSDBA group

OSDBA or OSASM or OSOPER refers to the operating system groups,which are being assigned with the database privileges. This mapping takes place during the time of the installation.

# The DBA_GROUP is the OS group which is to be granted OSDBA privileges.
# The OPER_GROUP is the OS group which is to be granted OSOPER privileges.
# The OSASM_GROUP is the OS group which is to be granted OSASM privileges.

An important point to be noted is that, only the members or OSDBA group can connect to the database instance with SYSDBA a privilege using operating system authentication

Finding OSDBA group

Most of the time we can easily find out the information from group name of the owner of the Oracle Binaries. But there are chances that the ownership is changed in later point of time mostly accidental. So if we wanted to find out the values set up initially that is during the time of the installation the best method is to look into the configuration file created during the time of installation

#1 go to your $ORACLE_HOME/rdbms/lib
#2 grep for “define SS_” in config.c file

Eg :

[oracle@localhost]$ cd $ORACLE_HOME/rdbms/lib

 [oracle@wysheid12crac60 lib]$ grep “define SS_” config.c

#define SS_DBA_GRP “dba”
#define SS_OPER_GRP “dba”
#define SS_ASM_GRP “”
#define SS_BKP_GRP “dba”
#define SS_DGD_GRP “dba”
#define SS_KMT_GRP “dba”

[oracle@localhost ]$

 In this example we can see that DBA group is assigned with the OSDBA privilege

Alternatively you can find out this information from your installation log files if it is available.In most cases the installation log files will be available in the log directory in Oracle inventory location.

Hope this helps.