Backing Up Oracle Database for Upgrading

Use this procedure to back up your existing Oracle Database before you attempt an upgrade.

Oracle recommends that you back up your Oracle database after you run the Pre-Upgrade Information Tool and cleanly shut down the database. To minimize downtime, you may perform an online backup or create a guaranteed restore point. Database Upgrade Assistant (DBUA) enables you to specify your backup and restore point.

Caution:

Before you make any changes to the Oracle software, Oracle recommends that you create a backup of the Oracle software and databases. For Oracle software running on Windows operating systems, you must also take a backup of the Windows registry. Without a registry backup, you cannot restore the Oracle software to a working state if the upgrade to Oracle Database 12c fails and you want to revert to the previous software installation.

Sign on to Oracle RMAN:
```
rman "target / nocatalog"
```

Run the following RMAN commands:

RUN
{
    ALLOCATE CHANNEL chan_name TYPE DISK;
    BACKUP DATABASE FORMAT 'some_backup_directory%U' TAG before_upgrade;
    BACKUP CURRENT CONTROLFILE FORMAT 'controlfile location and name';
}