Machines
intended to use SR-IOV run trusted workloads, SR-IOV may be enabled by
adding a registry
key of type DWORD with value 1 named IOVEnableOverride under
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows
NT\CurrentVersion\Virtualization and changing
state of the trusted virtual machines. If the system exhibits reduced
performance or
instability after SR-IOV devices are assigned to Virtual Machines,
consider disabling the
use of SR-IOV.} IovVirtualFunctionCount : 0
IovVirtualFunctionsInUse: 0
IovQueuePairCount : 0
IovQueuePairsInUse : 0
The following output is from another system with one adapter that does not support
SR-IOV and additional adapters that do support it:
PS C:> Get‐VMSwitch | Format‐List iov
IovEnabled : False IovSupport : False
IovSupportReasons : {This network adapter does not support SR-IOV.}
IovVirtualFunctionCount : 0
IovVirtualFunctionsInUse: 0
IovQueuePairCount : 0
IovQueuePairsInUse : 0
IovEnabled : True IovSupport : True
IovSupportReasons : {OK}IovVirtualFunctionCount : 62
IovVirtualFunctionsInUse: 10
IovQueuePairCount : 63
IovQueuePairsInUse : 10
IovEnabled : True IovSupport : True
IovSupportReasons : {OK}
IovVirtualFunctionCount : 6
IovVirtualFunctionsInUse: 2
IovQueuePairCount : 7
IovQueuePairsInUse : 2
You can run the PowerShell command Get-NetAdapterSriov to get SR-IOV support
adapter information on a system; it also shows the number of VFs supported by the
card. If a virtual machine is using SR-IOV successfully, then when you look at the
Networking tab of the virtual machine in Hyper-V Manager, that status will show “OK
(SR-IOV active).”
PS C:> Get‐NetAdapterSriov
Name : VM NIC
InterfaceDescription: Mellanox ConnectX-3 Pro Ethernet Adapter
Enabled : True