2.4 Validating Your Data Recovery Strategy

Practice backup and recovery techniques in a test environment before and after you move to a production system. In this way, you can measure the thoroughness of your strategies and minimize problems before they occur in a real situation. Performing test recoveries regularly ensures that your archiving, backup, and recovery procedures work. It also helps you stay familiar with recovery procedures, so that you are less likely to make a mistake in a crisis.

If you use RMAN, then one option is to run the DUPLICATE command to create a test database using backups of your production database. If you perform user-managed backup and recovery, then you can either create a new database, a standby database, or a copy of an existing database to test your backups.

2.4.1 Using BACKUP... VALIDATE

Using the RMAN BACKUP... VALIDATE command causes RMAN to read all of the specified database files that would be input for a specific backup task, without actually producing any backups as output. For example, BACKUP DATABASE VALIDATE causes RMAN to read all files that would be backed up in backing up the entire database and ensure that they are intact and not corrupted. All of the data blocks in the input files are validated, exactly as they are when a real backup takes place. This process can provide a useful integrity check for your database.

2.4.2 Validating RMAN Backups: VALIDATE and RESTORE VALIDATE

The RMAN VALIDATE and RESTORE VALIDATE commands should be part of ongoing testing of your recovery plan. VALIDATE causes RMAN to read specified backups on disk or tape and report whether they are intact and usable in a restore operation. RESTORE... VALIDATE causes RMAN to check whether the set of available backups is sufficient to restore the specified database objects. For example,RESTORE TABLESPACE TBS_1 VALIDATE selects backups sufficient to restore the named tablespace, just as RMAN does in a real restore operation, and reads the backups to ensure that they are present and not corrupted.

2.4.3 Testing Your Database Restore and Recovery Procedures

You can also test your backups by performing a complete test of your restore and recovery strategy onto different hardware. Ideally, use a hardware and software configuration for the test that is as similar as possible to the environment available to you in a real disaster recovery scenario.