Enable/Disable Restricted Session

 SYS @ GGATE1>select inst_id, instance_name, logins from gv$instance;

   INST_ID INSTANCE_NAME    LOGINS
---------- ---------------- ----------
         1 GGATE11          ALLOWED
         2 GGATE12          ALLOWED

-- Run the following command on each RAC node if applicable

SYS @ GGATE1>Alter system enable restricted session;

System altered.

SYS @ GGATE1>select inst_id, instance_name, logins from gv$instance;

   INST_ID INSTANCE_NAME    LOGINS
---------- ---------------- ----------
         1 GGATE11          RESTRICTED
         2 GGATE12          ALLOWED

SYS @ GGATE1>Alter system disable restricted session;

System altered.

SYS @ GGATE1>select inst_id, instance_name, logins from gv$instance;

   INST_ID INSTANCE_NAME    LOGINS
---------- ---------------- ----------
         1 GGATE11          ALLOWED
         2 GGATE12          ALLOWED