Oracle Active Data Guard – OPEN_MODE STATUS

I would to ask some question regarding Oracle Active Data Guard.

Currently, we are looking for an efficient way to get a real-time backup of Oracle Database. We tried to apply Oracle Active Data Guard on our testing servers running Windows Server 2012 R2 and an unlicensed Oracle 11g R2.

We applied these commands on the Physical Standby Server:

SHUTDOWN IMMEDIATE;
STARTUP MOUNT;
ALTER DATABASE OPEN READ ONLY;
ALTER DATABASE RECOVER MANAGED STANDBY DATABASE DISCONNECT FROM SESSION;

We checked the OPEN_MODE status of the database:

SQL> select database_role, open_mode from v$database;

We got this as a result:

DATABASE_ROLE    OPEN_MODE
---------------- --------------------
PHYSICAL STANDBY READ ONLY WITH APPLY

We tried to restart the Oracle Service (to simulate sudden power fluctuation or unintentional server shutdown). The OPEN_MODE status becomes:

DATABASE_ROLE    OPEN_MODE
---------------- --------------------
PHYSICAL STANDBY READ ONLY

Is it by default that the OPEN_MODE status became READ ONLY if we restart the service? Or do we really need to have a license to fully access Oracle Active Data Guard features so that the OPEN_MODE status will remain in READ ONLY WITH APPLY permanently even if we restart the Oracle server?