IBM 86655RY Hardware Maintenance Manual - Page 208

Create an array using three of the physical drives, leaving the fourth as a hot-spare drive. Then, create a logical drive within that array. The data is striped across the drives, creating blocks. Notice that the storage of the data parity (denoted by 5) also is striped, and it shifts from drive to drive. A parity block (5) contains a representation of the data from the other blocks in the same stripe. For example, the parity block in the first stripe contains data representation of blocks 1 and 2. * 1 2 3 * 4 5 6 * * 7 8 If a physical drive fails in the array, the ServeRAID controller switches read and write requests to the remaining functional drive in the RAID level-5 array, which is a hot-spare drive. * 2 1 3 4 * 5 * 6 * 8 7 198 Hardware Maintenance Manual: Netfinity 7600 - Type 8665 Models 1RY, 2RY