IBM 86655RY Hardware Maintenance Manual - Page 210

1 2 The data is striped across the drives, creating blocks in the logical drive. The storage of the data parity (denoted by 5) is striped, and it shifts from drive to drive as it does in RAID level-5. Notice that the spare drive is not striped. * 1 2 3 4 * 5 6 7 8 * 9 If a physical drive fails in the array, the data from the failed drive is compressed into the distributed spare drive. The logical drive remains RAID level-5E. When you replace the failed drive, the data for the logical drive decompresses and returns to the original striping scheme. * 1 2 3 * 4 5 6 * * 7 8 9 * Note: The ServeRAID Manager program Express configuration does not default to RAID level-5E. If you have four physical drives, Express configuration defaults to RAID level-5 with a hot-spare drive. Understanding RAID level-x0: RAID level-x0 refers to RAID levels-00, 10, 1E0, and 50. RAID level-x0 includes more physical drives in an array. The benefits of doing so are larger logical drives, increased performance, and increased reliability. RAID levels-0, 1, 1E, 5, and 5E cannot use more than 16 physical drives in an array. However, RAID levels-00, 10, 1E0, and 50 include more physical drives by managing an array of arrays, or a spanned array. The operating system uses the spanned array logical drive the same as a regular array logical drive. 200 Hardware Maintenance Manual: Netfinity 7600 - Type 8665 Models 1RY, 2RY