Recently, we put a Dell PowerEdge R720 in production. Unfortunately, it shipped with MBR and we have already started using it as a Hyper V host. Right now it has 6 600GB SAS drives in a RAID 10 on a PERC H710 controller. Dell configured it in one Virtual Disk. The problem is now that we need more space to store VMs. So we purchased 2 more 600GB disks, and I am planning on doing Online Capacity Expansion to grow the drive. this will cause it to grow to 2.2 TB. Isn't the limit on total disk size 2 TB? Should I only use 400GB of the new disk? Or can I use the whole disk and Windows will only use what it can? I was thinking my best option was to backup he server, erase the drive, and then reimage it onto the new disk. However, I really don't want to if I can avoid it. Suggesstions are welcome. Thanks!