Unfortunately, there is no way to do this without starting over. Option 1 As you described, you could split the disks up into separate VD's, leaving one 2TB or smaller for the OS.  This will cost you an extra disk's worth of disk space (VD0 RAID 5 = 2TB, VD1 RAID 5 = 4TB). Option 2 You could create "slices" across the disks - you would still have all 8 disks in a disk group, but you would carve out a smaller VD for the OS, then the remainder of the disk space could be a VD for data (each VD will show as a separate "disk" in Windows, so the second VD could be converted to GPT and be as large as you want, while the first VD remains an MBR disk for booting the OS in BIOS mode.  This will give you back an extra disk's worth of disk space over Option 1 (VD0 RAID 5 = 100GB, VD1 RAID 5 = 6.9TB). Option 3 You could switch to UEFI mode, create one VD with all 8 disks (as you have done), convert the disk to GPT, then install.  UEFI is required to boot GPT disks and GPT is required for disks larger than 2TB.  This would also allow you to keep 7TB of usable disk space. You might also consider a RAID 6, if you can afford yet another 1TB disk's worth of disk space.  Given that a disk rebuild could take 1-2 full days or more, a RAID 6 would provide better fault tolerance and protection during the vulnerable time that the disk is offline and/or rebuilding.  
Hello guys,  - We have a PowerEdge R720 server with a PERC H710 Mini storage controller that has 8 disk of 1 TB each one. - We created one virtual disk that includes the 8 physical disks configured on Raid 5. - We installed Windows 2008 Server R2 and we got 4469 GB unallocated space that we cannot use due to the limitation of the basic disks. [IMAGE] What we really want to do is to retrieve the unallocated space from the existing virtual disk and put it into a new one, so that we keep 3 disks for the virtual disk 0 and we use the 5 other for the new virtual disk 1.- Is that possible without destroying the data we have ?- Help please !Thanks in advance and sorry for the bad English :( 
Split one virtual disk into two virtual disks PERC H710