How to Defrag Mirrored Drives?

1. 
   Click the Windows "Start" button. Type "cmd" into the search text box and press "Enter." Your Windows command line utility opens.
   
   
2. Type "drive:" and press "Enter," where "drive" is the letter for your mirrored drive. This command points the prompt to your mirrored drive.
   
   
3. Type "defrag volume," where "volume" is the letter for your mirrored drive. For instance, if your mirrored drive is letter "x," type "defrag x" and press "Enter." Depending on the capacity of the volume and the speed of your processor, the defragmentation process could take several hours.