The standard four partition disk layout is referred to as basic disks.

Dynamic disks have fewer partition restrictions and can be remotely managed. Although basic disks can be converted to dynamic disks, there is no conversion process to go back to basic disk other than recreating the partition. New volumes can be extended, but volumes converted from basic disk cannot be extended. Boot volumes and system volumes cannot be extended.

Dynamic disks are required for stripe sets, mirrored disks, and RAID 5. Stripe sets stripe data across all disks so that all of the disk arms can be utilized as shown in the following diagram.

RAID 1 duplicates all data of both disks. Reads can then be divided between the two disks. Mirroring and duplexing are different terms used to describe how controllers are connected.

• Mirroring shares a controller
• Duplexing requires two controllers

		Disk 1
		Disk 2

With RAID 5, data is striped across the disks but parity information is also recorded. If a failure occurs on only one drive, data can be recreated with the parity information. A logical drive can be established with 3 to 32 physical drives.

RAID 1 is ideal for log files that use mostly write operations. RAID 5 is better for files that have more reads, e.g. database or AD. RAID 10 is the combination of RAID 1 mirroring and RAID 0 striping.

The following diagrams shows a typical configuration where the OS volumes are mirrored and the data volumes form a RAID 5 array.

		Drive C: Operating System RAID 1 Mirroring
			Drive D: Data RAID 5 Striped with Parity

Ideally, hardware RAID should be used, instead of Window software RAID support. The hardware includes its own processor, thereby relieving the CPU.

Keyboard Exercise

Use the Computer Management Disk Management Console to look at the disk partitions on your computer.