Requirements and considerations for running a virtual failover client on a Hyper-V server

Review the following requirements and considerations before creating a virtual failover client (VFC) on a Hyper-V server.

Requirements and considerations for all Hyper-V servers

     A VFC can run on the following:

-Windows Server 2008 R2 or higher with the Hyper-V role enabled

-Hyper-V Server 2008 R2 or higher

     The Hyper-V server must be a registered client of the Unitrends appliance from which you will create the VFC.

     The Unitrends Windows agent release 8.0 or higher must be installed on the Hyper-V server. After upgrading the agent, you must re-save the server on the Unitrends appliance from which you will perform WIR. Select Settings > Clients, Network, and Notifications > Clients. Select the Hyper-V server, and click Save. This forces the appliance to recognize the update to the agent on the Hyper-V server.

     The Hyper-V server must have enough resources to run the VFC. The minimum memory required to create a VFC and start the restore process is 1024 MB. The memory must be a multiple of 2.

     The appliance creates a VFC with a disk the same size as the disk on the original client. For Windows clients with disks larger than 2 TB, the VFC must be created on Hyper-V server version 2012 or higher. A VFC on Hyper-V server 2008 R2 is created with a VHD. A VFC on server version 2012/2012 R2 is created with a VHDX.

     The generation of the VFC VM is determined by the firmware interface type of the client. VFCs for BIOS-based clients are created as generation 1 VMs, and VFCs for UEFI-based clients are created as generation 2 VMs. (For more details about VFCs for UEFI-based clients, see Firmware interface type.)

     The VFC can run on the same Hyper-V server as a UEB VM or on a different Hyper-V server.

     A VFC for a UEFI-based client can run only on Hyper-V server version 2012 R2.

     A VFC cannot reside on a Hyper-V server using a selection of SMB shares as shared storage.

     Pass-through disks are supported on VFCs. After booting the VFC in live mode and configuring the network settings, you must refresh and reconnect any existing iSCSI targets on the client.

Requirements and considerations for Hyper-V clusters

     A VFC can run on a server in a cluster configuration. You must install Unitrends Windows agent version 8.0 or higher on each node and add each node and the cluster to the appliance from which you will create the VFC. Every node in the cluster must have the same agent version installed.

     To create a clustered VFC, you must select the cluster when specifying the location for the VFC. You cannot specify an owner node. If you select an individual node in the cluster, the VFC will not be clustered.

     For a clustered VFC, you must select the network switch common to all nodes in the cluster. If you do not select this switch, a VFC in live mode that fails over to another cluster will lose network connectivity.

     To run the VFC on 2008 R2 servers in a cluster configuration, you must enable DCOM and WMI Virtualization access for all nodes in the cluster. For instructions, see KB 1774.

     During live migration of a clustered VFC, the Unitrends appliance cannot perform restores to the VFC, verify or audit the VFC, or boot it in live mode. If a restore or verify attempt is made during a live migration, the appliance will wait several minutes and then attempt the operation again. If you attempt to boot the VFC in audit or live mode during a live migration, the appliance notifies you that the operation cannot be performed because of the migration and prompts you to attempt the operation again later.