6.5.1

You can use a comma-separated list to set values for the vf_param parameter, where each entry
indicates the number of virtual functions for a port. A value of 0 ensures that SR-IOV is not enabled
for that physical function.
If you have two dual port NICs, you can set the value to w,x,y,z, where w,x,y, and z is the number of
virtual functions you want to enable for a single port. For example, to create 30 virtual functions
distributed on two dual port Intel cards by using the ixgbe driver, run the following command for the
ixgbe driver and the max_vfs parameter:
esxcli system module parameters set -m ixgbe -p max_vfs=0,10,10,10
2 Restart the host to create the virtual functions.
What to do next
Associate a virtual function with a virtual machine adapter by using the SR-IOV passthrough network
adapter type. See Assign a Virtual Function as SR-IOV Passthrough Adapter to a Virtual Machine.
Virtual Machine That Uses an SR-IOV Virtual Function Fails to
Power On Because the Host Is Out of Interrupt Vectors
On an ESXi host, one or more virtual machines that use SR-IOV virtual functions (VFs) for networking are
powered off.
Problem
On an ESXi host, one or more virtual machines that use SR-IOV virtual functions (VFs) for networking fail
to power on if the total number of assigned virtual functions is close to the maximum number of VFs
specified in the vSphere Configuration Maximums guide.
The virtual machine log file vmware.log contains the following message about the VF:
PCIPassthruChangeIntrSettings: vf_name failed to register interrupt (error code 195887110)
The VMkernel log file vmkernel.log contains the following messages about the VF assigned to the
virtual machine:
VMKPCIPassthru: 2565: BDF = vf_name intrType = 4 numVectors: 3
WARNING: IntrVector: 233: Out of interrupt vectors
Cause
The number of allocatable interrupt vectors scales up with the number of physical CPUs on an ESXi host.
An ESXi host that has 32 CPUs can provide a total of 4096 interrupt vectors. When the host boots,
devices on the host such as storage controllers, physical network adapters, and USB controllers consume
a subset of the 4096 vectors. If these devices require more than 1024 vectors, the maximum number of
potentially supported VFs is reduced.
vSphere Networking
VMware, Inc. 163