Delta Push

This solution consists of two operations that run on each protected database: the incremental-forever backup strategy, and real-time redo transport. Both operations involve protected databases pushing changes to the Recovery Appliance.

In an incremental-forever strategy, only one incremental level 0 backup to the Recovery Appliance is required in the lifetime of each protected file. The initial level 0 backup does not contain committed undo blocks or currently unused blocks.

Note:

The elimination of committed undo and currently unused blocks is only supported for SBT full backups to the Recovery Appliance or Oracle Secure Backup. It is not available for SBT backups to other backup products.

In normal operation, the Recovery Appliance automatically performs the following steps for each incremental level 1 backup:

Receives a scheduled incremental level 1 backup from each protected database
Validates the incoming backup to protect against physical block corruptions
Compresses the backup using specialized block-level algorithms
Writes the backup to a delta store in a Recovery Appliance storage location

The incremental-forever strategy greatly reduces the backup window and overhead because no full backups are ever required after the initial incremental level 0 backup. If the strategy includes real-time redo transport, then backup windows are further reduced because traditional archived log backups are not necessary. Also, Recovery Appliance takes on the burden of validation, deduplication, and compression.

Note:

Blocks compressed using table or Hybrid Columnar Compression remain compressed in the RMAN backup and during the Recovery Appliance ingest phase.