Performing Oracle Advanced Recovery - OCP: Oracle Database 12c Administrator Certified Professional - page 289

Each of the cases listed before have used cases that are associated with them, but the basic
mechanism of performing the duplication is still the same. We will cover how to perform
these duplications next.
Performing an RMAN Database Duplication
Duplicating a database is an operation that many DBAs perform. RMAN provides the
DUPLICATE DATABASE command to help ease the database-duplication process. As you saw
previously, there are different ways to do a duplication, but most of them have to do with
how you connect to RMAN to do the duplication (for example, if there is or is not a recov-
ery catalog to connect to) and the type of duplication you need to perform (for example,
active database duplication vs. backup based database duplication).
With respect to the actual procedures that you follow, they will only differ, for the
most part, depending on if you are doing an active database duplication or a backup-based
database duplication. In the next sections, we will discuss the steps needed to perform
these kinds of duplications.
Preparing to Duplicate Your Database
Preparing to duplicate your database requires a few steps:
1. Backing up the target database (backup-based database duplication only)
2. Making backup images available to the destination host (backup-based database
duplication only)
3. Deciding where to put the duplicate database-related files
4. Preparing the auxiliary instance for the duplication
Let's look at each of these steps in more detail.
Backing up the target database is not required if you are using active data-
base duplication. If you are doing backup-based duplication, you will need
a complete backup of the target database. Follow the steps outlined in
Chapter 3 to perform an RMAN backup of your database. The database can
be in NOARCHIVELOG or ARCHIVELOG mode.
Making backup images available to the destination host is not required if you are using
active database duplication. If you are doing backup-based duplication, you will need to
make the backup set pieces associated with the backup of the target database and all asso-
ciated archived redo logs available to the destination host. This is so they can be read by
RMAN during the duplication process. You can make everything available to the destina-
tion host by putting the backup set pieces on shared devices (such as Network File System,
or NFS) or some other shared disk environment. You could also manually copy the needed
files to the destination host via Secure File Transfer Protocol (SFTP) or some equivalent
file-copy protocol.