Oracle Error RMAN-12017: could not locate pieces of backup set key string

Oracle Error Message

RMAN-12017: could not locate pieces of backup set key string

Reason for the Error

Copies of the specified backup set key could not be accessed on any of the allocated channels.

Solution

Allocate additional channels on other nodes of the cluster or, if the backup pieces has been deleted, use the CROSSCHECK BACKUP command to correct the recovery catalog or target database control file entries.