OCP CBT Question 667

Please solve the following question.

You are managing a critical production database. The database instance PROD is currently down for maintenance. You need to restart the listener (LISTENER) which serves this database, ensuring it will be able to accept connections for PROD once the instance is brought back up. The listener.ora file contains only the default listener entry and no SID_LIST_LISTENER section. Which lsnrctl command and subsequent action will ensure PROD clients can connect as soon as the database instance is started?

## listener.ora
LISTENER =
  (DESCRIPTION_LIST =
    (DESCRIPTION =
      (ADDRESS = (PROTOCOL = TCP)(HOST = localhost)(PORT = 1521))
    )
  )

Execute lsnrctl reload LISTENER. No further action is needed on the database side.

Execute lsnrctl stop LISTENER, then lsnrctl start LISTENER. The database instance will dynamically register upon startup.

Modify listener.ora to include a SID_LIST_LISTENER entry for PROD, then execute lsnrctl reload LISTENER.

Execute lsnrctl start LISTENER. Then, after the instance is up, manually register the service using ALTER SYSTEM REGISTER;.