Windows Server 2008 R2 6

In Hyper-V 2008 R2, you don't have to shut down your system in order to add extra storage. This is known as Hyper-V Dynamic Storage. Back in Hyper-V 2008 R1, we were only able to use 4 processors. Hyper-V 2008 R2 now works with 8 processors with up to 74 logical processors.
You can also use up to 1TB of RAM. We can also do Hyper-V clustering now, which allows another system to take over the role of a failed one. Hyper-V clustering requires expensive hardware to work properly. We can now also support 384 virtual machines with up to 512 virtual processors.

We can also do Live Migration which allows migration of virtual machines across different processors from the same vendor. Do note that Dynamic Storage only allows adding of virtual SCSI hard disks. However, you'll need to boot up with a virtual IDE disk, so you cannot hot-add IDE disks.



To do hot-adding of SCSI, simply go to the Hyper-V management console from the Server Manager. We can then add SCSI hard drives from a VM's properties by going to the SCSI controller (which wasn't available in 2008 R1). After adding, you can go to Server Manager > Storage > Disk Management to initialize the new disk.



You can also remove and swap the disks to other virtual machines quickly from the same place. The disks are VHD files, which can also be mounted back to your host operating system. You can mount VHDs from anywhere - even from a thumbdrive.