Here's an overview:

When you use basic disks, you're limited to creating four primary partitions per disk or three primary partitions and one extended partition with unlimited logical drives. Basic and dynamic disks differ in the number of partitions (on basic disks) and volumes (on dynamic disks) that each can contain. Basic disks also use the partition tables (stored in the Master Boot Record—MBR—at the beginning of the disk) that Windows XP, Win2K, NT 4.0, Windows Me, Win9x, and MS-DOS support. Basic disk volumes also include support for multidisk volumes—such as volume sets, stripe sets, mirror sets, and stripe sets with parity—created in NT 4.0 or earlier. (XP doesn't support these multidisk basic volumes but Win2K does.)

XP Professional Edition and Win2K support dynamic disk storage. When you initialize a physical disk as dynamic, it's called a dynamic disk and contains dynamic volumes, such as simple volumes, spanned volumes, striped volumes, mirrored volumes, and RAID 5 volumes. Dynamic disk storage is divided into volumes instead of partitions. Dynamic storage lets you manage disks and volumes without restarting Windows.

Volumes have different layouts (simple volumes, spanned volumes, striped volumes). Basic disks used to provide different layout types (spanned, mirrored, RAID 5) with partitions. However, XP Pro, Win2K, and Win.NET Server provide these layouts in dynamic disk volumes.

Dynamic disks introduce the concept of disk groups. Disk groups (collections of disks organized as entities) help administrators prevent data loss by organizing dynamic disks. All dynamic disks within a disk group store configuration data for the entire group (this data is stored in a 1MB region at the end of each dynamic disk). All configuration information for simple, spanned, mirrored, striped, or RAID 5 volumes within a disk group is stored on each disk in the group. This "database" of configuration information is replicated and kept up-to-date across all dynamic disks in the group. If you lose a dynamic disk or you move the disk group to another system, the OS maintains the configuration information for the disk group. Win2K systems allow only one disk group (Disk Group 0—DG0) per computer.


>Hi Tracy
>
>What exactly did you mean by "dynamic disks"?
>
>Thanks
>Simon
>
>
>>Hi Jim,
>>Just in case you were interested, I checked this product out and really liked it. The only problem I could find is that it does not support cloning dynamic disks. I had to use Ghost 2003 for that capability.
>>
>>tracy
>>
>>>Thanks, Simon. Looks quite reasonable! Have you tried it with a server? Does it do NTFS?
>>>
>>>>Hi
>>>>
>>>>I found a handy utility that allows you to copy an entire drive under W2k/XP right from the desktop. You do not have to boot into DOS. I have used it a number of times to clone drive to make a complete bootable backup copy on another drive.
>>>>
>>>>The product is called Casper XP at:
>>>>
>>>>http://www.fssdev.com
>>>>
>>>>Just thought someone else might be interested in this product. I use it for backup purposes.
>>>>
>>>>Simon