It is difficult for an architect or an organization to select the right Hyper-V high-availability or migration technology to deploy in the production environment. There are so many choices. In addition to the Hyper-V high-availability & migration technologies that were introduced in Windows Server 2008 RTM and R2, the new Hyper-V Version 3.0 running on Windows Server 2012 Operating System comes with a bunch of new migration technologies. These technologies not only provide the high-availability of virtual machines running on a Hyper-V environment but also help reduce the IT cost. An example of one of these new technologies is the ‘Shared-Nothing Live Migration’ technology, introduced in Windows Server 2012. Not only can you migrate live virtual machines without downtime but without the additional cost of shared storage devices since they aren’t required for this. Similarly, using ‘Hyper-V Replica’ of Windows Server 2012 allows you to configure a disaster recovery scenario without having to configure the ‘Windows Failover Clustering’ service!
Read more here : https://www.simple-talk.com/sysadmin/virtualization/hyper-v-migration-technologies/