Windows Server 2008 R2 & Microsoft Hyper-V Server 2008 R2 – Hyper-V Live Migration Overview & Architecture can be downloaded from here: http://www.microsoft.com/downloads/details.aspx?FamilyID=fdd083c6-3fc7-470b-8569-7e6a19fb0fdf&DisplayLang=en.
Description: One of the most highly anticipated new features in Windows Server® 2008 R2 Hyper-V™ is live migration. This document describes the live migration feature of Windows Server® 2008 R2 Hyper-V™ in detail, including how live migration moves running VMs and requirements for implementing live migration.
Because no one like to read manuals, I will excerpt from the paper:
How Live Migration Works:
- All VM memory pages are transferred from the source Hyper-V™ physical host to the destination Hyper-V™ physical host. While this is occurring, any VM modifications to its memory pages are tracked.
- Pages that were modified while step 1 was occurring are transferred to the destination physical computer.
- The storage handle for the VM’s VHD files are moved to the destination physical computer.
- The destination VM is brought online on the destination Hyper-V™ server.
- Further details and pictures are in the whitepaper.
- Hyper-V™ live migration is supported on the following editions of Windows Server 2008 R2: Windows Server 2008 R2 x64 Enterprise Edition and Windows Server 2008 R2 x64 Datacenter Edition.
- Live migration is also supported on Microsoft® Hyper-V™ Server 2008 R2.
- Microsoft Failover Clustering must be configured on all physical hosts that will use live migration.
- Failover Clustering supports up to 16 nodes per cluster.
- The cluster should be configured with a dedicated network for the live migration traffic .
- Physical host servers must use a processor or processors from the same manufacturer.
- Physical hosts must be configured on the same TCP/IP subnet.
- Physical hosts must have access to shared storage.
Recommendations and Notes:
- A clustered shared volume is recommended for VM storage in a cluster where live migration will be used.
- One live migration can be active between any two cluster nodes at any time. This means that a cluster will support number_of_nodes/2 simultaneous live migrations. For example, a 16-node cluster will support 8 simultaneous live migrations with no more than one live migration session active from every node of the cluster.
- A dedicated 1 Gigabit Ethernet connection is recommended for the live migration network between cluster nodes to transfer the large number of memory pages typical for a virtual machine.
- The cluster configurations that have been validated by vendors can be found through the listings in the FCCP program under the heading of The Microsoft Support Policy for Windows Server 2008 Failover Clusters at this URL: http://support.microsoft.com/default.aspx?scid=kb;EN-US;943984
Deploying Live Migration Steps
- Configure Windows Server 2008 R2 Failover Clustering.
- Connect both physical hosts to networks and storage.
- Install Hyper-V™ and Failover Clustering on both physical hosts.
- Enable Cluster Shared Volumes.
- Make the Virtual Machines highly available.
- Test a Live Migration.
For detailed, step-by-step instructions see the deploying live migration whitepaper at this URL: http://go.microsoft.com/fwlink/?LinkId=139667
Some Interesting Tidbits about Windows 2008 R2 and Hyper-V:
- Enhanced Processor Support: Hyper-V Hosts will support up to 32 Cores (guest remains at 4 I believe)
- Networking Enhancements: jumbo frames support, TCP Chimney support, new Virtual Machine Queue (VMQ) feature for allowing physical network cards to use direct memory access (DMA) to place contents of packets directly into memory.
- Dynamic VM Storage: Now supports the addition and removal of VHD’s and pass-through disks while a VM is running. For hot plug and removal of storage you will need Hyper-V Integration Services.
I am sorry if in fact you do like to read manuals (this is the Cliff Notes version).