About Oracle RMAN
RMAN performs a wide variety of automated backup and recovery functions. During a backup or a restore, RMAN provides the interface to the databases, and it extracts and inserts data.
To start a database backup or restore, the database administrator runs the rman command. You can run this command from the command line, a script, or an application such as NetBackup. The RMAN script is used as a parameter to the rman command and specifies the operations to be performed (for example, backup or restore). The RMAN script also defines other components of the operation such as the database objects to be backed up or restored.
During a backup or restore, RMAN controls the data streams going into or out of a database. RMAN can access storage devices when it is integrated with a media management system, such as the system that NetBackup provides.
RMAN provides true incremental backups. An incremental backup backs up data files and includes only the blocks that have been changed since the last incremental backup. For more information on the backup and recovery process, see your Oracle documentation.
Table: Oracle RMAN terms explains Oracle RMAN terms as they pertain to NetBackup.
Table: Oracle RMAN terms
Term | Definition |
|---|---|
backup set | A backup set is a backup of one or more data files, control files, SPFILEs, and archived redo log files. Each backup set consists of one or more binary files called backup pieces. Backup pieces are written in a proprietary format that only RMAN can create or restore. |
instance | An Oracle database instance consists of a System Global Area (SGA) and the Oracle background processes. When Oracle starts a database, it allocates an SGA and starts Oracle background processes. The SGA is de-allocated when the instance shuts down. |
Real Application Clusters (RAC) | RAC is an option that allows multiple concurrent instances to share a single physical database. |
RMAN | RMAN backs up, restores, and recovers database files. RMAN starts Oracle database server processes on the target database. These Oracle database server processes perform the backup and restore. RMAN performs backup and recovery procedures, and it greatly simplifies the tasks that administrators perform during these processes. However, RMAN cannot directly manage the storage devices and media that are used in its backups. So it must be integrated with an application that has these capabilities. NetBackup for Oracle provides device and media management capabilities by integrating RMAN with NetBackup and its media management software. Also, RMAN can access NetBackup's automatic scheduling facilities and its graphical interfaces. |
RMAN repository | An RMAN recovery catalog or the database control file is a repository for the information that RMAN uses and maintains. RMAN uses this information to determine how to run requested backup and restore actions. |
rman command | The rman command starts an RMAN backup or restore. |
The RMAN script specifies the commands for RMAN to perform (for example, backups and restores). For information on RMAN commands and script files, see your Oracle documentation. The following directory contains example RMAN shell scripts: Windows: install_path\NetBackup\dbext\Oracle\samples\rman UNIX: /usr/openv/netbackup/ext/db_ext/oracle/samples/rman These example scripts run RMAN commands and are fully commented to explain the features that are used. You can review these examples and use them as a starting point for developing backup, restore, and recovery scripts. |
For more information on RMAN terminology, see your Oracle documentation.