If an existing entry is found in the unreadable sector database, the corresponding sector on the reconstructing drive will be added to the unreadable sector database and a critical MEL event will be g...If an existing entry is found in the unreadable sector database, the corresponding sector on the reconstructing drive will be added to the unreadable sector database and a critical MEL event will be generated for the data lost on the reconstructing drive. Two unreadable sectors will be added to the unreadable sector database, one for the defective sector on the data drive and the second for the data that could not be regenerated on the reconstructing drive.