Software RAID/Extend two or more hard disks

Windows 2000, XP and Server all include support for dynamic disks. What are these dynamic disks? They are disks that don't work with any other operating system except the aforementioned. However they do allow you to mirror drives, and join two or more physical drives into one big drive. This document will explain how to setup both a RAID and an extended drive.

Basic and Dynamic

Your hard disks are by default basic disks. In order to extend or mirror a disk, the disk must first be converted to a dynamic disk. It's important to note here that any disks that you do convert to dynamic will be unable to boot another operating system, and at the time of writing, cannot be 'seen' by any other operating system other than those mentioned above, so if you have a Linux or old Windows 9x dual boot system, do not convert the boot drive to dynamic.

In order to convert the disks to dynamic, right-click on My Computer and choose Manage. You should see a window similar to the one shown below. Right click on all the drives one by one, selecting 'Convert to Dynamic'.

In the setup shown above (click to enlarge), there are 3 hard disks in the computer, a 10Gb with Windows installed on it, a 30Gb and a 60Gb. The 30Gb is mirrored (RAIDed) onto the 60Gb, leaving another 30Gb free on the 60Gb drive.

Note: Ideally you should use identical drives for this, if that isn't possible, try to use drives that are of the same speed and that have the same amount of cache, you should also try to keep the drives on separate IDE channels for best performance.

RAID

RAID is possibly your best friend should you have a large amount of data, too large to backup to CD/DVD media. If you want a RAID setup, right-click on the source partition and choose 'Mirror', this will then prompt you to choose the disk on which to create the duplicate partition.

Once you have done this, a new partition will be created on the disk, all data from the source partition will be duplicated onto the destination drive, this can take an extremely long time depending on how much data you have.

Extending a disk

Extending a disk allows you to in essence, merge two partitions on different disks so they use the same drive letter. This can be great for improving disk access times, if your retrieving data from 2 disks at the same time as oppose to jumping all over one. There will be slightly additional CPU usage when using extended disks, but the speed increase from the extended partitions is worth it.

To extend a disk, simply right-click on a disk and select 'Extend', select the disk to extend onto, and click OK.