The crosscheck command is used to validate the physical backup is located where rman thinks it is. rman
stores the backup information either in the controlfile
or in the rman
repository. If a restore operation needs to be carried out, rman
determines the best suitable backupset and archivelog files required to successfully perform the recover process. If the backup is not where it is supposed to be then there will be problems.
In the following scenario rman
validates the backup sets:
There are three backupsets, this can be queried using the LIST BACKUP
command (A):
LIST BACKUP OF TABLESPACE USERS SUMMARY;
This is only to find out the backupset tag where a particular tablespace was stored. Afterwards, the CROSSCHECK
command is issued against a particular backupset (B). In the first case the validation was successful for all backup pieces involved (all backup pieces were marked as AVAILABLE).
CROSSCHECK BACKUPSET TAG='Tag Name';
On the second execution of the CROSSCHECK
command...