The matrix of considerations for backup and DR for Hyper-V is not simple, for example there are several methods to backup running VMs such as Windows Server Backup, DPM, diskshadow.exe, as well as non-Microsoft solutions such as Symantec Backup Exec.
Capability
Host-Based
Agent-Based
SAN snapshots
Protection of VM configuration
X
Protection of Host & Cluster configuration
Protection of Virtualization-specific data such as VM snapshots
Protection of data inside the VM
Protection of data inside the VM stored on pass-through disks
Support for VSS-based backups for supported operating systems and applications
Support for Continuous Data Protection (DPM)
Ability to granularly recover specific files or applications inside the VM
For more help on options and considerations, see:
Backup and Disaster Recovery for Server Virtualization: http://technet.microsoft.com/en-us/magazine/cc895627.aspx
This Fix it Solution automates registering the Microsoft Hyper-V VSS writer with Windows Server Backup: How to back up Hyper-V virtual machines from the parent partition on a Windows Server 2008-based computer by using Windows Server Backup
Off-line Virtual Machine Servicing Tool: http://technet.microsoft.com/en-us/library/cc501231.aspx
Taylor Brown's blog post explains away some of the confusion around backup/snapshot in Hyper-V: http://blogs.msdn.com/taylorb/archive/2008/08/20/backing-up-hyper-v-virtual-machines-using-windows-server-backup.aspx
How to enable Windows Server Backup support for the Hyper-V VSS Writer : http://blogs.technet.com/askcore/archive/2008/08/20/how-to-enable-windows-server-backup-support-for-the-hyper-v-vss-writer.aspx
Backing Up Hyper-V Virtual Machines Using Windows Server Backup: http://blogs.msdn.com/taylorb/archive/2008/08/20/backing-up-hyper-v-virtual-machines-using-windows-server-backup.aspx
Windows Server 2008 Backup and Recovery Overview : http://technet.microsoft.com/library/cc770593.aspx
Windows Server Backup Step-by-Step Guide for Windows Server 2008 : http://technet.microsoft.com/en-us/library/cc770266.aspx
Hyper-V Backup: what's supported?: http://social.technet.microsoft.com/Forums/en-US/winserverhyperv/thread/587474ff-8146-44bb-8ef7-c80a366b07f4/
Microsoft Data Protection Manager trial: http://technet.microsoft.com/dpm/bb727240.aspx