During the Oracle Database installation, the ORA_DBA, ORA_OPER, ORA_HOMENAME_DBA, ORA_HOMENAME_OPER, ORA_HOMENAME_SYSBACKUP, ORA_HOMENAME_SYSDG, ORA_HOMENAME_SYSKM, and ORA_HOMENAME_SYSRAC groups are created and users assigned to these groups.

Members of these groups are granted operating system authentication for the set of database system privileges each group authorizes. Oracle recommends that you use different operating system groups for each set of system privileges.