IBM 86625RY Hardware Maintenance Manual - Page 115

3. Select the appropriate RAID level from the pull-down list. Note The number of hard disk drives in the array determines the RAID levels available for the array. If the array contains one hard disk drive, you can select only RAID level-0 for the logical drive. If the array contains two hard disk drives, you can select RAID level-0 or RAID level-1 for the logical drive. If the array contains three or more hard disk drives, you can select RAID level-0, RAID level-1, or RAID level-5 for the logical drive. 4. Enter the Requested Space in the entry field. The ServeRAID program uses the maximum available space for the selected RAID level to calculate the default value that it assigns. Note The actual logical drive size may be slightly different from what you type in the Requested Space field. The RAID level and the number of hard disk drives determine the size of the logical drive. For example, a disk array consisting of three, 1 GB hard disk drives with a requested RAID level-0 logical drive of 1000 MB will actually contain only 999 MB because the data is striped across all three drives, with 333 MB on each drive. 5. Select OK to create the logical drive. Notes 1. If you plan to use the Logical Drive Migration (LDM) feature, do not define more than seven logical drives. The LDM feature requires one free logical drive to perform the migration. Refer to "Logical drive migration administration" on page 109 for more information. 2. If you plan to use the Change RAID Level function of the LDM feature, you must assign the same RAID level to all logical drives within a single disk array. Refer to "Change RAID levels" on page 109 for more information. Initializing logical drives: Initializing a logical drive erases the first 1024 sectors on the drive and prevents access to any data previously stored on the drive. To initialize a logical drive: Netfinity 5500 M20 - Type 8662 107