With the RTM launch of Windows Server 2012 R2 comes an amazing set of features via such a short release cycle. This post details the top 8 improvements now found in Hyper-V Replica in Windows Server 2012 R2.
When upgrading from Windows Server 2012 to Windows Server 2012 R2 it is no longer required to re-IR your protected VMs. New features such as cross-version live migration allow it to be easy to maintain DR story across OS upgrades. IT professionals can also select to upgrade their primary site and replica site at different times. This is because Hyper-V Replica will now replicate virtual machines from a Windows Server 2012 environment to a Windows Server 2012 R2 environment.
30 second replication frequency
IT professionals were allowed to replicate their virtual machines at a preset 5minute replication frequency in Windows Server 2012. Microsoft's aspirations to bring down this replication frequency, backed by the IT community, was on a ask of providing flexibility to a set different replication frequencies to different virtual machines. Windows Server 2012 R2 now allows asynchronous replication of virtual machines at either 30second, 5mins or 15mins frequency.
Linux guest OS support
Hyper-V Replica's first release has been agnostic to the application and guest OS. Certain capabilities however were unavailable on non-Windows guest OS in it’s initial avatar. Windows Server 2012 R2, provides file-system consistent snapshots and injects IP addresses as part of the failover workflow that allows for tighter integration with non-Windows OS offerings to address this.
A replica copy to a third site can now be extended via the ‘Extended replication’ feature. The added functionality provides an additional layer of protection to recover from a disaster. A replica copy can now be available within a prescribed site (ex: ClusterA->ClusterB in the primary datacenter) and extend the replication for the protected VMs from ClusterB->ClusterC (in the secondary data center). To recover from a disaster in ClusterA, an IT professional can now quickly failover to the VMs in ClusterB and continue to protect them to ClusterC.
A significant amount of architectural investments were made to lower the IOPS and storage resources required on the Replica server. The most important of these was the ability to move away from snapshot-based recovery points to undo logs based recovery points. The changes provide a profound impact on the way the system scales up and consumes resources.
Windows Server 2012 Hyper-V Replica was closely integrated with various Hyper-V features such as storage migration, VM migration, etc. Windows Server 2012 R2 now allows IT professionals to resize a running VM and have the ability to continue to replicate the virtual machine without having to re-IR the VM should the VM be protected.
Hyper-V Recovery Manager
Hyper-V Recovery Manager (HRM) is a Windows Azure Service allowing for the management and orchestration of various DR workflows between the primary and recovery datacenters. HRM does not replicate virtual machines to Windows Azure. Data is replicated directly between the primary and recovery datacenter. HRM is the disaster recovery management head offered as a service on Azure.
Those looking to learn best practices regarding Hyper-V Replica should review the Introduction to Hyper-V Jump Start provided on Microsoft Virtual Academy.