RAID-1 and RAID-5
You can only use the operating system to create RAID-1 volumes and RAID-5 volumes on dynamic disks running on Windows Server 2003 or Windows 2000 Server computers.
Both RAID-1 volumes and RAID-5 volumes are considered fault tolerant because they can handle a single disk failure and still function normally. RAID-1 volumes and RAID-5 volumes both require that an equal amount of disk space be available on each disk that will be used.
A RAID-1 volume must use two physical disks. A RAID-5 volume must use at least three physical hard disks, up to a maximum of 32 physical disks.
Note that hardware-based fault-tolerant solutions are operating system independent and are more robust and reliable than software-based fault-tolerant configurations. By installing one or more RAID controller adapter cards into a server, you can set up several different types of hardware fault tolerance, such as RAID-1, RAID-5, RAID 10 (mirrored volumes that are part of a striped array set), and RAID 0+1 (striped volumes that are part of a mirrored set).
When you use hardware RAID, you can retain basic disks or you can convert disks to dynamic. Hardware RAID is hidden to Windows Server 2003. Of course, it's less expensive to implement a software solution, such as setting up mirrored volumes or RAID-5 volumes using the Disk Management console in Windows Server 2003, but often the performance, reliability, and flexibility of hardware-based RAID far outweighs its extra cost.