NetVault Plug-in for Oracle 12.3

When FRA is enabled, Backup Destination options are enabled on the Backup Options tab. These options let you select the destination for the backup. These options let you define a media destination strategy that best meets your needs.

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NetVault Backup Media Manager: This option is the default. When selected, RMAN opens an “SBT_TAPE” channel and writes the backup files to the backup media that is managed by NetVault Backup and specified in the Device options section of the Target tab. NetVault Backup can manage a range of backup devices, including disk-based media, VTLs, and tape drives, which lets you implement a Disk-to-Disk-to-NetVault Backup Media Manager backup strategy. Even though FRA has been enabled for the database, it is not used to store backup recovery files. This option is ideal for users who want to maintain a dedicated FRA for permanent files such as copies of the current Control File and online redo logs or Flashback logs.

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Disk (Backup to FRA): When selected, RMAN opens a DISK channel and only writes the backup files to the FRA. Storing the backup recovery files in the FRA provides the fastest restore possible with RMAN because RMAN can restore the files directly from the FRA without having to read files from backup media. Because the FRA is typically disk storage residing on the same local or shared storage as the datafiles, it does not provide complete protection against complete media failure, corruption, or disaster recovery. To ensure that the backup recovery files are stored in offsite storage, you can use the Both NetVault Backup Media Manager and Disk or perform periodic Flash Recovery Area Backups to back up the backup recovery files stored in the FRA-to-backup media managed by NetVault Backup.

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Both NetVault Backup Media Manager and Disk (Backup to FRA then Backup FRA to NetVault Backup Media): Implementing a NetVault Backup Media Manager and Disk backup strategy provides the most protection with the fastest restores. When selected, RMAN opens a DISK channel and writes the backup files to the FRA followed by a backup of the backup recovery files stored in the FRA-to-backup media managed by NetVault Backup in the same backup job. This option lets you perform the fastest recovery possible from isolated media failure and data corruption while providing offsite protection for complete media failure or disaster recovery. Selecting the Both NetVault Backup Media Manager and Disk option lengthens the duration of the backup job because RMAN must perform two types of backups in the same backup job.

If you want to store backup recovery files in the FRA for faster restores and you require offsite protection for disaster recovery, but you do not want to lengthen the duration of the daily backup jobs, there is an additional option for performing daily backups to the FRA while performing Flash Recovery Area Backups on a different independent schedule. For example, when Full Backups are performed every Sunday at 11:00pm, they are performed to Disk. When Incremental Backups are performed Monday through Saturday at 11:00pm, they are also performed to Disk. However, a Flash Recovery Area Backup to backup media is performed weekly every Sunday at 10:00pm before the Full Backup is performed. Additionally, you can perform the Flash Recovery Area Backup at any interval that meets business requirements.

Oracle Flashback technology

Oracle Database versions 10g and later provides a group of features known as Oracle Flashback Technology. Flashback Technology features include the Oracle Flashback Database, Oracle Flashback Table, and Oracle Flashback Drop. Flashback Technology supports viewing past states of data and winding data back and forth in time without requiring you to restore the database from backup. Depending on the changes to your database, Flashback Technology features can often reverse the unwanted changes more quickly and with less effect on database availability than media recovery.

According to Oracle Corporation, the Oracle Flashback Database lets you rewind an Oracle database to a previous time to correct problems caused by logical data corruptions or user errors. Plug‑in for Oracle provides support for Flashback Database through the NetVault Backup WebUI, which enables point-and-click Flashback Database options as an alternative to media recovery.

If an FRA is configured and you have enabled the Flashback Database functionality, you can use the FLASHBACK DATABASE command to return the database to a prior time. Flashback Database is not true media recovery because it does not involve restoring physical datafiles. Flashback Database is preferable to using the RESTORE and RECOVER commands in some cases because it is faster and easier and does not require restoring the whole database.

The time it takes to rewind a database with FLASHBACK DATABASE is proportional to how far back in time you need to go and the amount of database activity after the target time. The time it would take to restore and recover the whole database could be much longer. The before images in the flashback logs are only used to restore the database to a point in the past; forward recovery is used to bring the database to a consistent state at some time in the past. The Oracle database returns datafiles to the previous point, but not auxiliary files, such as initialization parameter files.

Quest recommends that you enable Flashback Database for Oracle 10g and later databases so that the administrator can flashback the database to correct problems caused by logical data corruptions or user errors. For more information, see Oracle Flashback Technology in Oracle Database Concepts and to Configuring Oracle Flashback Database and Restore Points in the Oracle Database Backup and Recovery User’s Guide.