4.5 Using RMAN to Validate Database Files

You can use the VALIDATE option of the BACKUP command to verify that database files exist and are in the correct locations, and have no physical or logical corruptions that would prevent RMAN from creating backups of them. When performing a BACKUP... VALIDATE, RMAN reads the files to be backed up in their entirety, as it would during a real backup. It does not, however, actually produce any backup sets or image copies.

If the backup validation discovers corrupt blocks, then RMAN updates the V$DATABASE_BLOCK_CORRUPTION view with rows describing the corruptions. You can repair corruptions using block media recovery, documented in Oracle Database Backup and Recovery Advanced User's Guide. After a corrupt block is repaired, the row identifying this block is deleted from the view.

For example, you can validate that all database files and archived logs can be backed up by running a command as follows:

BACKUP VALIDATE DATABASE ARCHIVELOG ALL;

The RMAN client displays the same output that it would if it were really backing up the files. If RMAN cannot validate the backup of one or more of the files, then it issues an error message. For example, RMAN may show output similar to the following:

RMAN-00571: ===========================================================
RMAN-00569: =============== ERROR MESSAGE STACK FOLLOWS ===============
RMAN-00571: ===========================================================
RMAN-03002: failure of backup command at 08/29/2002 14:33:47
ORA-19625: error identifying file /oracle/oradata/trgt/arch/archive1_6.dbf
ORA-27037: unable to obtain file status
SVR4 Error: 2: No such file or directory
Additional information: 3

You cannot use the MAXCORRUPT or PROXY parameters with the VALIDATE option.