RMAN is the component of oracle database that is used to perform backup and recovery operations.It can make consistent and inconsistent backups, perform incremental and full backups ,backup either whole database or portion of it.
RMAN has its own scripting language and has interface with many popular backup software solutions.
An Oracle database to which RMAN is connected with the TARGET keyword. A target database is a database on which RMAN is performing backup and recovery operations. RMAN always maintains metadata about its operations on a database in the control file of the database. The RMAN metadata is known as the RMAN repository.
Here are some commands to start with Recovery manager:
set following parameters and then start the listener
$ export ORACLE_BASE=/u01/app/oracle;
$ export ORACLE_HOME=$ORACLE_BASE/product/11.2.0/db_1;
$ export ORACLE_SID=FIN;
$ export PATH=$ORACLE_HOME/bin:$PATH;
$ lsnrctl start;
Here after starting listener and before mounting database start the recovery manager using below commands:
$ RMAN TARGET SYS/ORACLE;
After starting RMAN we can have multiple options to take which kind of backup we want.
Some regular commands are:
RMAN> Backup database plus archivelog delete input;
The command delete input indicates to delete archivelog files after backup. Whole database backup is backup of data file plus control file. We can optionally include archived red log files and server parameter.
RMAN> backup tablespace users;
Here backup of only users tablespace users is taken by RMAN
RMAN> backup as copy datafile 4;
It indicates backup of datafile 4 as normal copy- paste like in operating system.It does not concerned with unused data blocks or free blocks within datafile.
Flash_recovery_area is the directory where all the backup files are generated.