3.2.1 Create a Backup Copy of the Primary Database Datafiles
You can use any backup copy of the primary database to create the physical standby database, as long as you have the necessary archived redo log files to completely recover the database. Oracle recommends that you use the Recovery Manager utility (RMAN).

See Oracle High Availability Architecture and Best Practices for backup recommendations and Oracle Database Backup and Recovery Advanced User's Guide to perform an RMAN backup operation.

3.2.2 Create a Control File for the Standby Database
If the backup procedure required you to shut down the primary database, issue the following SQL*Plus statement to start the primary database:

SQL> STARTUP MOUNT;

Then, create the control file for the standby database, and open the primary database to user access, as shown in the following example:

SQL> ALTER DATABASE CREATE STANDBY CONTROLFILE AS '/tmp/boston.ctl';
SQL> ALTER DATABASE OPEN;

Note:

You cannot use a single control file for both the primary and standby databases.