A write operation from the iSeries™ server detects that the disk unit that is to contain the data has failed. The write operation is to disk unit 3, sector 1. The following actions occur:
Write operations require multiple read operations (n-2 reads, where n is the number of disk units) and only one write operation for the new parity information. Data from disk unit 3 will be rebuilt during synchronization after disk unit 3 is replaced.