Hello, Shane Brasher here, and I wanted to take a minute today to talk to you about a Windows Server 2012 Hyper-V / System Center 2012 Data Protection Manager (DPM) SP1 supportability issue. First let’s briefly discuss an exciting new feature of Windows Server 2012 Hyper-V. There is a new functionality added to the Hyper-V role that enables you to implement Business Continuity and Disaster Recovery. This functionality is called Hyper-V replication or Hyper-V Replica. This new feature allows you to have a Hyper-V Primary server that replicates it’s virtual machines to another server hosting the Hyper-V replica role. Any changes made on the Primary Hyper-V are replicated over to the Hyper-V Replica server every 5 minutes, thus if the Primary Hyper-V server should fail then the Hyper-V Replica can take over the workload. More information can be found at the link below:
The important thing to note about this is that while the DPM agent can be installed on both servers with no issues and you can backup the Primary DPM server as usual with no problems, on the Hyper-V Replica server you can enumerate the virtual machines and “
even be able to back them up successfully, however
backing up or restoring the Hyper-V replica is not supported.
Due to the inner workings of the Hyper-V replication architecture which may be in progress during the time of a DPM backup, there can be no guarantees of a successful backup or restore of virtual machines that reside on the Hyper-V Replica server. You will still be able to backup other types of data on the Hyper-V Replica such as flat files and system state for example.
A common question that is often asked is “if the Replica is a complete backup of the Primary Hyper-V server virtual machines, then why would I want to back that up again with DPM if redundancy is already built-in.” Well, then answer is you wouldn’t need to backup the Hyper-V Replica but you still may want to backup the Primary Hyper-V server for many reasons.
First, you may have a mandatory retention range set via service level agreement that you may want to adhere to. Second, you may choose to perform a restore from a previous point in time for example 2 weeks ago. Third, you may choose to perform a restore from a previous point in time to another Hyper-V server for testing without interrupting productivity. Forth, it’s possible there may be some catastrophic corruption on one of the virtual machines. For example, perhaps you have a virtual machine that has a virus and the virtual machine along with the virus is replicated over to the Hyper-V Replica.
In conclusion the key points are this:
Backing up or restoring virtual machines from a Windows Server 2012 Hyper-V Replica is not supported. If you need an extra layer of redundancy for your Windows Server 2012 Hyper-V virtual machines, you can achieve this by backing up the Hyper-V Primary server.
Shane Brasher | Senior Support Escalation Engineer
| Management and Security Division