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waverobber asked
I have a box with 6 drives. 2 x 350 GB , as RAID 1 and 4 x 1.2TB as RAID 6. The OS (Server 2012) was installed on the Raid 1 and the Raid 6 was reserved for for virtual machines. After studying Hyper-V basics, I found that storage pools may be a more efficient way to proceed than the original Raid 6 I had prepared. However, I also read that to setup a storage pool, any existing volumes and Raid arrays needed to first be deleted.

Following the elimination of the volume on the Raid 6, the storage pool manager was able to see the available disks. I set out to use a mirrored and/or stripped pools and get an error message saying there was not enough disk space. The only option I was able to use was "Simple." I then went to the Raid controller and eliminated the Raid 6 array. Following that, the storage pool manager was unable to see the available disks.


My question is how do I turn the Raid controller off on the four drives and use HBA? Is this even possible? Why was the pool working (simple) when the disks, according to the Raid controller, were setup as Raid 6, but without a volume on the drive(s)?

I like the idea of Raid simply because of eventual failure of drive(s). However, the storage pool seems cool not only because of failed drive replacement (which I can't get to work), but because the pool(s) actually show up on the host OS...
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Simple Geek from the '70s
Distinguished Expert 2019
it showed up as simple as as far as storage spaces was concerned it was 1 drive. which is how raid shows itself to the operating system.  Do you have a physical raid card with memory and a battery backup or were you using the fakeraid controller that is included with most modern motherboards?

Storage spaces needs to see all 4 disks .. once you removed them from the raid array and rebooted, device manager must be able to see all 4 drives plus the 1 raid 1 volume.
Now you can create a storage space, then add the 4 drives, create the storage space volume, specifying the pool capacity and type storage space


Hi David and thanks for your rapid reply. In answering your question, yes I do have a hardware RAID controller (Dell Perc H710P SCSI). I already checked the configuration settings in the BIOS and found no way to turn off the RAID for the four drives. If I (ctrl+r) during boot, I am able to delete the Raid 6 array, while keeping the OS, Raid 1 intact. Is there a way following boot to get the OS to see the available disks?
David Johnson, CDSimple Geek from the '70s
Distinguished Expert 2019

Storage spaces requires a higher level of access than your perc card is willing to give .. storage spaces normally works in a JBOD environment (Just a Bunch of Disks)


I stumbled upon an answer that seems to fit my scenario...

Breaking RAID

One of the new features in Windows Server 2012, called Storage Spaces, provides a software-based way to manage multiple physical hard disks. It essentially replaces hardware RAID with a software solution. If you intend on using this functionality, you'll first have to remove any existing RAID configurations on your system.

Our test R520 came with five SAS disks configured in two RAID groups. The first group consisted of two hard disks in a RAID 0 mode for the operating system. The second group used the other three disks configured in RAID 5 for data storage.

Use the configuration tool available during the boot process to change RAID settings. The R520 goes through several stages as it boots with options to enter System Setup (F2), Lifecycle Controller (F10), BIOS Boot Manager (F11) or PXE Boot (F12), followed by the Broadcom Network Card manager (Ctrl-S) and finally the Perc H710P Mini RAID configuration tool (Ctrl-R).

Once you have the RAID configuration utility open you must break any RAID groups that you wish to reconfigure for Storage Spaces. With the Perc H710P Mini RAID controller, first select the Disk Group to delete and then press F2, followed by choosing Delete Disk Group.

With this step complete, next add a new Disk Group for each individual drive by selecting the controller and again pressing F2, followed by Create New VD (Virtual Disk). Each disk must be in its own Disk Group and configured for RAID 0.


Once again, thank you David. Your answer got me looking in the right direction. Made total sense that the RAID 6 was showing up as 1 disk. One last note however, is taking into account my above solution (all disks are individual RAID 1 arrays), what has precedence in the event of disk failure? The RAID 1, or Windows Storage Pool?