Windows Server 2008 R2 – Promoting a Secondary Plex to Primary

software-raidwindows-server-2008-r2

I have a Windows Server 2008 R2 install that uses Windows software RAID to mirror the drive. The primary drive is failing. I installed a new drive to the set and syncing is almost complete. Once the sync finishes, I want to promote the secondary plex to to the primary booting drive, break the set, and remove the failing drive from.

How would I do this?

Best Answer

That turned out to be much easier than I expected, but let me back up. Doing research didn't turn up much, though looking for a boot.ini and not finding it provided the first real clue. In Vista builds and forward, boot.ini is replaced by Boot Configuration Data (BCD).

  • In msconfig.exe, I set the default boot to secondary plex on Disk 1
  • Reboot the server to confirm I was booting to the secondary plex
  • Shut down the system
  • Disconnect disk 0
  • Boot the system to see what happens
  • Log in to the desktop, open the Server Manager -> Storage -> Disk Manager
  • Disk 0 is marked as missing
  • I removed the mirrors

And the server is now waiting patiently for the new disk to arrive to create the new mirror.

I don't know if this is the right way to go about it but it seems to be working.

Update: Doing this will not change the friendly name of the secondary plex in the boot menu.

After doing the steps to promote the secondary plex, as outlined above, one must BCDEdit.exe using the /set operation to update the friendly name. This requires admin privileges on the server.

bcdedit /set {current} description "Windows Server 2008 R2 (Installed 1/6/2020)"
Related Topic