Check database is in restricted mode Oracle

Check the logins status of column for restricted mode in table v$instance of Oracle database:

select logins from v$instance;

LOGINS
----------
ALLOWED

select logins from v$instance;

LOGINS
----------
RESTRICTED

ALLOWED : Database not in restricted mode

RESTRICTED : Database in restricted Mode

Enable the restricted mode of the Oracle database:

alter system enable restricted session;

Disable the restricted mode of the Oracle Database:

alter system disable restricted session;

You can also start the Oracle database in restrict mode:

startup restrict

In RAC database Start the database in Restrict Mode

-- In Case of RAC database:
srvctl start database -d orcl -o restrict

In RAC Environment, Verify the database is in Restrict mode

[oracle@RAC01 ~]$ srvctl status database -d orcl -v
Instance ORCL is running on node RAC01. Instance status: Restricted Access.
Instance ORCL is running on node RAC02. Instance status: Restricted Access.