Basic Software Raid in SBS 2008

On March 29, 2009, in sbs 2008, by

I was wondering if you know where I could learn how to set up software mirrored disks for the C: drive in a SBS 2008 system. This is an AT BIOS machine (not EFI), and using MBR disks (not GPT). Microsoft has kb951985 for the GPT disk case, I’m looking for a corresponding procedure for MBR disks.

MBR is pretty easy.  A step by step is here: but basically the process is that once you add a second drive to the server the drive will want to be initiallized.  Choose the type of drive of MBR

Go into computer management and it will see the new drive.

Click on Disk Management and you’ll need to then initialize the disk.

Choose MBR as the type of drive. 

Now convert the main drive to a dynamic drive to prepare it for software mirroring.  (Of course make a backup first).

Choose the drive

Click through the “are you really sure” messages.

Now that the main drive is dynamic, right mouse click on that C drive and and choose “Add Mirror”

 Select the other drive to make the mirror on.

Convert the mirror to a dynamic drive as well

You’ll notice the sync is now underway.

Some RAID purists will say you need a hardware raid and that software isn’t good enough. One thing to keep in mind is that with this basic software raid you don’t have a lot of diagnostics as to what is going on with the underlying raid sync. 

But if you want cheap raid, throw another drive in a system and see how easy it is to set it up.


2 Responses to Basic Software Raid in SBS 2008

  1. John says:


    If you loose a drive in your Windows software RAID, is the boot sector written to both drives? Is there a certainty of rebooting without regard for which of the drives in your example fail? (I haven’t seen this happen since NT4, and I vaguely remember the answer at that time was NO.)


  2. Anthony Short says:

    With a configuration like this, how do you boot from the secondary drive if the primary fails and is removed from the machine? In SBS 2003 I would make a boot floppy and use that to boot from the secondary. With SBS 2008 we have the BCD boot mechanism and it’s not clear to me if it’s possible to make a boot floppy or how to boot the secondary. I’ve tried disconnecting the primary from a pair created with the instructions above and the secondary isn’t bootable. Thank you.