After-imaging combined with backup and roll-forward recovery lets you recover the database if a disk holding a database file is damaged. After-imaging is optional; you must enable it before a disk fails, and you must have performed backups to use roll-forward recovery. You should also keep backups and archived AI files until they are no longer required.
The technique for recovering the database depends on the circumstances that require recovery. The next sections provide scenarios and explanations of how to use the PROUTIL and RFUTIL utilities to handle the following problems:
Loss of the DB files, BI files, or both
