This step-by-step article describes how to mirror the system and boot partition in Windows Server 2003. This scenario is based on the assumption that the system and boot files are located on disk 0 and that disk 1 is unallocated space.

First some definition:

RAID 1 mirroring is an arrangement of hard disks that creates an exact copy (or mirror) of a set of data on two or more disks. This is useful when read performance or reliability are more important than data storage capacity.

  • At least two hard-disk drives; IDE, small computer system interface (SCSI), or mixed architecture is permissible.
  • The second drive must be at least the size of the volume on which the operating system boot and system files reside to permit mirroring.
  • The Windows Server 2003 system and boot files must reside on the same volume to be mirrored.


  • To add a mirror to the primary drive for redundancy so that when either of the drive fails, quick recovery can be done.

There are two parts in this process -- Converting your Disks to Dynamic Disks and Adding the Actual Mirror.

Converting to Dynamic Disks


1. Right click on My Computer on your desktop and click Manage. Under Storage, click Disk Management.

2. Right click on Disk0 and choose Convert to Dynamic Disk...

3. Tick Disk0 and Disk1 and click OK.

4. Review the disks to be converted, click Convert to proceed.

5. The next menu is a warning that other operating systems installed on any volumes on any disks can no longer start. Make sure that you are not dual booting other operating systems. Click Yes to proceed.

6. Now for the final confirmation. Click Yes to proceed.

7. Click OK when prompted. This will restart your server.

8. At this point, new drivers where installed to support the dynamic disks. You will now be prompted to restart - AGAIN.

9. That completes the process of converting to dynamic disks. You can now proceed to adding actual mirror.

Adding the Mirror

On my primary drive, I have setup pre-setup two partitions. One for the operating system and program files and another for my data. We are going to mirror both.

1. Go to Disk Management as described in the previous process.

2. Right click on the first partition and click Add Mirror..

3. Select the second drive (Disk 1), then click Add Mirror.

4. The partition will now sync to the second drive. Notice that the mirrored partition will now be color coded. It will look something like this.

5. Repeat the same step to the second partition.

When the sync-ing process is done. You now have a RAID 1 system when means, you have 1 parity. Your data is safe even if 1 drive fails.

Part 2 of this mini HOW TO will discuss on how to recover from a failed drive.