Before you can connect a virtual machine to a virtual function, you must configure the virtual functions of the physical NIC on your host by using a host profile.

You can also enable SR-IOV virtual functions on the host by using the esxcli system module parameters set vCLI command on the NIC driver parameter for virtual functions in accordance with the driver documentation. For more information about using vCLI commands, see vSphere Command-Line Interface Documentation.


  • Verify that the configuration of your environment supports SR-IOV. See SR-IOV Support.

  • Create a host profile using the SR-IOV capable host as a reference. For more information about host profiles, see the vSphere Host Profiles documentation.

Launch the vSphere Client and log in to a vCenter Server system.


  1. In the vSphere Client, click Home and select the Host Profiles main view.
  2. Select the host profile from the list and click Edit Profile.
  3. Expand Kernel Module Configuration > Kernel Module and select the kernel module for the physical function driver.
  4. Expand Kernel Module Parameter and select the parameter of the physical function driver for creating virtual functions.
    For example, the parameter for the physical function driver of an Intel physical NIC is max_vfs.
  5. Click Edit.
  6. In the Value text box, type a comma-separated list of valid virtual function numbers.
    Each list entry is the number of virtual functions that you want to configure for each physical function. A value of 0 means SR-IOV will not be enabled for that physical function.
    For example, if you have a dual port, set the value to
    where x or y is the number of virtual functions you want to enable for a single port.

    If the target number of virtual functions on a single host is 30, you might have two dual port cards set to 0,10,10,10.

    Note: The number of virtual functions supported and available for configuration depends on your system configuration.
  7. Click OK.
  8. Remediate the modified host profile to the target host.


After the virtual functions become enabled on the host, the physical NIC no longer shows up as a host network adapter in the Network Adapters list within the Configuration tab for the host. It appears in the Advanced Settings list for the host.

What to do next

Associate a virtual function with a virtual machine as a PCI device for networking through Direct Path I/O.