Configuring PERC 3 93Arranging ArraysYou must arrange the arrays to provide additional organization for the drivearray. You must arrange arrays so that you can create system drives that canfunction as boot devices.You can sequentially arrange arrays with an identical number of drives sothat the drives in the group are spanned. Spanned drives can be treated asone large drive. Data can be striped across multiple arrays as one logicaldrive.You can create spanned drives using the PERC 3 BIOS ConfigurationUtility.Creating Hot SparesAny drive that is present, formatted, and initialized but is not included inan array or logical drive can be designated as a hot spare.You can designate drives as hot spares using the PERC 3 BIOSConfiguration Utility.Creating Logical DrivesLogical drives are arrays or spanned arrays that are presented to theoperating system. You must create one or more logical drives. The logicaldrive capacity must include all of the disk space in an array. If an array withdrives with mixed sizes, the smallest common size is used and larger diskdrives are truncated. The logical drive capacity can also be larger than anarray by using spanning. PERC 3 supports up to 40 logical drives.Configuration StrategiesThe most important factors in RAID array configuration are:• Drive capacity• Drive availability (fault tolerance)• Drive performanceYou cannot configure a logical drive that optimizes all three factors, but it iseasy to choose a logical drive configuration that maximizes one factor at theexpense of the other two.
