【正文】 r recoveryrelated files: ? Simplifies the location of database backups ? Automatically manages the disk space allocated for recovery files ? Does not require changes to existing scripts ? Puts database backups, archive logs, and control file backups in the flash recovery area 19 Copyright 169。 2023, Oracle. All rights reserved. Backing Up the Flash Recovery Area RMAN BACKUP RECOVERY FILES。 FILE_TYPE USED RECLAIMABLE FILES 16 Copyright 169。 2023, Oracle. All rights reserved. Flash Recovery Area Space Usage ? Configure the retention policy to the minimum value appropriate for your database. ? Back up the archive log files regularly and delete the files upon pletion of the backup. ? Use the RMAN REPORT OBSOLETE and DELETE OBSOLETE mands to remove backups and file copies that are not required. 15 Copyright 169。 DB_RECOVERY_FILE_DEST_SIZE = 2G 13 Copyright 169。 2023, Oracle. All rights reserved. Using a Flash Recovery Area with RMAN You can configure RMAN to use the flash recovery area. Database area RMAN backup process Flash recovery area DB_RECOVERY_FILE_DEST = 39。 2023, Oracle. All rights reserved. Backup Destinations Backups can be written to: ? Disk directory ? Media Management Library (tape device) – Typically used for disaster recovery, when disk backups are lost ? Flash recovery area – This is a disk area set aside for backup and recovery and flashback database purposes. – You define the location and the size. – Files are automatically named by using Oracle Managed Files. – Files are automatically retained and deleted as necessary. 9 Copyright 169。 2023, Oracle. All rights reserved. Steps for Configuring RMAN 1. Determine the repository location: control file or recovery catalog. 2. Define database and environment variables. 3. Start RMAN and connect to the target and, optionally, the recovery catalog databases. 4. Configure persistent settings. 6 Copyright 169。 2023, Oracle. All rights reserved. Backup and Recovery: Review The major backup and recovery–related topics covered in the Database Administration I Course are: ? Types of failure that can happen – Statement, session, instance, media, and so on ? How to configure ARCHIVELOG mode ? How to automate backups ? How to do incremental backups ? How to perform and tune instance recovery 3 Copyright 169。Copyright 169。 2023 Oracle. All rights reserved. 2 Copyright 169。 2023, Oracle. All rights reserved. Server session Channel Server session Enterprise Manager Recovery Manager Components Target database Recovery catalog database Auxiliary database Disk Flash recovery area Channel Channel MML Options Recovery Manager (RMAN) 5 Copyright 169。 2023, Oracle. All rights reserved. RMAN Repository Data Storage: Comparison of Options Control file: – Simpler administration – Default Recovery catalog: – Replicates control file data – Has room for more data – Can service many targets – Can store RMAN scripts Metadata Backup set list Image copy list . . . 8 Copyright 169。 2023, Oracle. All rights reserved. Media Management Recovery Manager Media management server software Media management library Server session (channel) Oracle Secure Backup with builtin MML Or 11 Copyright 169。/u01/oracle/fra39。 2023, Oracle. All rights reserved. Monitoring the Flash Recovery Area with EM 14 Copyright 169。 2023, Oracle. All rights reserved. V$FLASH_RECOVERY_AREA_USAGE You can query V$FLASH_RECOVERY_AREA_USAGE to view the flash recovery area disk space usage. SQL SELECT file_type, 2 percent_space_used AS used, 3 percent_space_reclaimable AS reclaimable, 4 number_of_files AS number 5 FROM v$flash_recovery_area_usage 。 2023