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<table border="0" cellspacing="0" width="100%"><tr><td width="20%">[[Migrating Hyper-V Virtual Machines Using Import/Export|Previous]]<td align="center">[[Hyper-V Essentials|Table of Contents]]<td width="20%" align="right">[[Understanding and Installing Hyper-V Integration Services|Next]]</td><tr><td width="20%">Migrating Hyper-V Virtual Machines Using Import/Export<td align="center"><td width="20%" align="right">Understanding and Installing Hyper-V Integration Services </td></table><hr>  <htmlet>hyperv</htmlet>  In the previous chapter we looked at the the migration of Hyper-V virtual machines using a technique that required the virtual machine to be powered off or placed into a saved state. The downside to this approach is that it is a manual process and any service provided by the virtual machine is interrupted during the migration process, hardly an acceptable solution in mission critical and enterprise level environments.

Before a running virtual machine can be migrated from one host to another there are some mandatory requirements thant that must first be met:

- * Hyper-V 2008 R2 must be deployed on both hosts. The first version of Hyper-V does not support live migration.

- * Source and destination Hyper-V hosts must be configured as a Failover cluster with shared storage enabled.

- * Source and destination systems must be using shared storage (i.e. via SAN or iSCSI configurations)

- * Source and destination systems must be running processors from the same manufacturer. It is not, for example, possible to migrate a virtual machine from an Intel based host to one containing an AMD CPU.

- * The virtual machine on which the migration is to be performed must be configured as ''Highly Available'' and to use Cluster Shared Volumes.

- * The virtual machine's ''Automatic Start Action'' setting must be set to do ''Nothing''. * All Hyper-V hosts in the Failover cluster must be configured to boot from the same drive letter. In other words, a host that boots from the C drive cannot perform a live migration to a host that boots from the D drive.

- * '''Configuration transfer''' - The source host transfers the configuration data for the virtual machine to the destination host.

- * '''Destination VM creation''' - Based on the configuration data the destination host creates a new virtual machine and allocated allocates adequate memory.

- * '''Transfer of memory pages''' - The memeory pages used by the virtual machine on the source host are transferred to the destination host. During this process, the source host monitors the memory and records any changes that take place after each page is transferred. Modified pages are then resent to the destination host.

- * '''Transfer of state''' - Register and device state are sent to the destination server.

- * '''Transfer of storage''' - The source host transfers the shared storage handle to the destination host where it is used to access the virtual hard disks (VHDs) and passthrough disks required by the virtual machine.

- * '''VM brought online''' - The migrated virtual machine is brought online on the destination host.

- * '''Network Re-direction''' - The network environment is modified to direct traffic intended for the virtual machine to the destination host.

Assuming that the system requirements outlined earlier in this chapter have been met and a virtual machine is running on a host within such an environment, a live migration can be now initiated.

Live migrations may be initiated either from within the ''Failover Cluster Manager'' console or using Windows PowerShell. A migration may be performed using the manager as follows:

In the Failover Cluster Manager snap-inconsole, if select the cluster that you want to configure is not displayed, which the source and destination Hyper-V hosts (referred to as nodes within the context of a cluster) belong. In the tree in the left hand pane of the console tree, select the node on which the virtual machine is currently running, right-click Failover Cluster Manager, click Manage a Cluster, on the virtual machine in the main pane and then select or specify the cluster that you want''Live migrate virtual machine to another node''.

In the console tree (on the left)Finally, select the destination node under which you want to move a clustered virtual machine using initiate the live migration. Right-click Once completed, the virtual machine resource displayed in the center pane (not on the left), and then click Live migrate virtual machine node will be listed as being assigned to another node. Select the different node that you want to move the virtual machine to. When migration is complete, the virtual machine is one it was origianlly running on the new node. To verify that the virtual machine successfully migrated, you will see the virtual machine listed under the new node (in ''Current Owner)''.

Open To open a PowerShell. Click window, select ''Start, point to -> All Programs, click -> Accessories -> Windows Powershell 2.0, and then click -> Windows Powershell 2PowerShell''.0.  The Failover Clustering feature must be installed on the computer on which you are starting Within the PowerShell session. To window, install the Failover Clustering feature, typeas follows:

Add<pre>Import-Module FailoverClusters </pre>

TypeTo perform the live migration, enter a command using the following syntax:

<pre>Get-Cluster “<Cluster Namecluster>” | Move-ClusterVirtualMachineRole -Name “<VM vm group name>” -Node “<Destination destination node name>” </pre>

* <Cluster Namecluster> is represents the name of the cluster that contains the virtual machine is included into be migrated.

* <VM group namedestination node> is represents the name of the destination host node within the Failover cluster to which the virtual machine resource groupis to be migrated.

<Destination node namehtmlet>hyperv</htmlet> is the name of the destination node to which you would like to move the virtual machine using live migration.