|1. Production database
||This is the database that you want to back up.
|2. Server process
||This server process writes data to disk for RMAN; talks to the Media Management Layer to write tape; and connects to the production database.
|3. Recovery catalog database
||This database maintains information about Recovery Manager backups.
||The disk(s) holds the backed up data.
|5. Media Management Layer
||This contains the software to manage writing to tape subsystems.
||This holds the backed up data.