Forever incremental backups help reduce the time taken for backup operations, even for large databases. There is less load on the source database during backup operations and the amount of time that the database is in “hot backup” mode is reduced.
The IntelliSnap backups are faster since they use capabilities of the hardware. Image copy operations are also efficient since RMAN generates an incremental backup to the image copy location very quickly, using Oracle Block Change Tracking. The snapshots are available for recovery and for instant clone operations as long as they are retained. However, the snapshots are usually retained for a limited time and are not suitable for long-term retention. The backup copy method is used to copy these snapshots to long-term retention on the Commvault disk library. The Block-Level Backup Copy interface supports incremental copying of snapshot data to the Commvault disk library. This facilitates the forever incremental backups during backup copy operations. For the backups to be used for long-term retention, it is best to create fully merged copies of database images as self-contained jobs. A synthetic full backup operation combines full and incremental backups into a single job on the Commvault disk library. This backup can be stored for long term retention and used for instant clones.
You can use a combination of incremental backups and synthetic full backups for Oracle copy data management.
Use the block-level interface with incremental backups and synthetic full backups to back up your database. Use traditional log backups to back up the log files. When you use this strategy, you schedule incremental backups on a regular basis, for example weekly, and schedule a synthetic full backup to meet your Recovery Point Objective (RPO).
The incremental backups (also called forever incremental backups) work as follows:
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If you do not have a full backup, the software performs a full backup for the first incremental backup.
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All subsequent incremental backups contain only the changes from the last backup, regardless of the type.
The forever incremental backup strategy means that the Commvault software reads the changes and copies them to your database copy.
Run a synthetic full backup to create a new full backup that meets your RPO.
Procedure
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Perform an incremental backup of the database subclient.
Use the schedule option and select the schedule that you configured for the database backup (Backup Options dialog box, Schedule).
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Perform an incremental backup of the log subclient.
Use the schedule option and select the schedule that you configured for the log backup (Backup Options dialog box, Schedule).
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Perform a synthetic full backup of the database subclient.
Use the schedule option and select the schedule that you configured for the synthetic full database backup (Backup Options dialog box, Schedule).
Results
You can use the following backups or backup copies for instant clone creation:
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Every incremental backup snapshot or its backup copy
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Every synthetic full backup
You can list the snapshots from the subclient or instance level. The software displays all incremental, synthetic full snapshots on all copies. You can mount the snapshots by using the CommCell Console for native access. For more information, see Viewing Snapshot Details and Mounting and Unmounting Snapshots.