It is the case that some instance types can only support one network interface with accelerated networking enabled.
Example that can support more than one enabled: Standard_DS2_v2
Example that can only support one (see above error): Standard_D2s_v3
If you try to create a VMSS (for example) with instance type Standard_D2s_v3 with two NICs both with accelerated networking, you get the following error:
compute.VirtualMachineScaleSetsClient#CreateOrUpdate: Failure sending request: StatusCode=400 – Original Error: Code='VmSizeRestrictedToSingleNicWithAcceleratedNetworkingEnable' Message='Virtual machine /subscriptions/49fc77ed-d214-4789-9936-9fcdc9028d53/resourceGroups/ZAZA-K8S/providers/Microsoft.Compute/virtualMachineScaleSets/us3-prod-dog-zaza-2d523fec4d3051f8 with size Standard_D2s_v3 is restricted to have only one network interface with accelerated networking enabled.' Details=
The feature request is to include this information: "How many NICs with accelerated networking can this instance type support" in the resource skus endpoint (and in the corresponding golang SDK): https://docs.microsoft.com/en-us/rest/api/compute/resource-skus/list
I have been communicating with azure support on this, the internal number they are tracking the feature request with is 10736394