Oracle Database 10g stores and manages files related to its backup and recovery operations in a different nondatabase location called the flash recovery area. A flash recovery area is specified by the init.ora parameters DB_RECOVERY_FILE_DEST (location) and DB_RECOVERY_FILE_DEST_SIZE (size). For a RAC environment, these two parameters should be the same on all instances. Use of the flash recovery area will ease your burden on backup and recovery operations.
The flash recovery area can be an Oracle-managed directory or a file system, or an ASM disk group. (ASM disk groups are discussed in Chapter 4.) The flash recovery area is used by Oracle for its archive logs and by RMAN for its backups.