End-to-End Data Validation

A basic principle of backup and recovery is to ensure that backups can be restored successfully. To ensure that there are no physical corruptions within the backed-up data blocks, backups require regular validation. Validation typically involves running an RMAN RESTORE VALIDATE job regularly, along with running periodic full restore and recovery operations to a separate machine.

Recovery Appliance provides end-to-end block validation, which occurs in the following stages of the workflow:

Recovery Appliance validation

The Recovery Appliance automatically validates the backup stream during the backup ingest phase, before writing the backups to disk. The Recovery Appliance also validates the backup before sending it back to the original or alternate database server during the restore phase. Therefore, no manual RESTORE VALIDATE step is required.

In addition, a background task running on the Recovery Appliance periodically validates the integrity of the virtual full backups in the delta pools (see "Delta Pools"). The goal of this task is to check each block of each virtual full backup of each protected database and to work behind the scenes when minimal activity is occurring. By default, the validation task runs every 14 days following the last completed validation of a database’s current set of backups on disk.

Just as with data file backups, the Recovery Appliance validates the integrity of redo log blocks during every operation, including receiving redo from the protected database, and storing it in compressed archived log backup sets.
Oracle Automatic Storage Management (ASM)

Oracle ASM stores the backup and redo data for the Recovery Appliance. Oracle ASM mirrored copies provide redundancy (see "Recovery Appliance Storage Locations").

If a corrupted block is read on the primary mirror, the Recovery Appliance automatically repairs the block from the mirrored copy. This mechanism resolves most isolated block corruption cases.
Tape library

Recovery Appliance validates blocks when it copies them to tape, and also when it restores them from tape (see "Tape Archival").
Downstream Recovery Appliance in a replication configuration

If you configure replication, then the downstream Recovery Appliance validates data during the backup ingest and restore phases (see "How a Downstream Recovery Appliance Processes Backups").

None of the preceding backup validation processes occur on the production database hosts, thus freeing production resources for more critical operational workloads.

Note:

Oracle Maximum Availability Architecture best practices recommend that you still perform periodic full database recovery tests to verify operational practices and to detect issues that might occur only during media recovery.