XenServer 6.0 provided improved SR-IOV support, maintained with v 6.5

Note that SR-IOV is supported only with SR-IOV enabled NICs listed on the XenServer Hardware
Compatibility List and only when used in conjunction with a Windows Server 2008 guest and requires Intel VT-d capable systems. Generally with SR-IOV VF, functions that require VM mobility like live migration, workload balancing, rolling pool upgrade, High Availability and Disaster Recovery are not possible.