You can create instances that use the Single Root I/O Virtualization (SR-IOV) specification by modifying the metadata parameters of the flavor and image used to create the instance. SR-IOV is a specification that allows a single Peripheral Component Interconnect Express (PCIe) physical device under a single root port to appear as multiple separate physical devices.

About this task

For more information about SR-IOV requirements and supported features, see the vSphere Web Client documentation.

The following table describes the key components of SR-IOV and their role.

Table 1. SR-IOV Components in the VMware Integrated OpenStack context



Nova Compute

  • Collects the list of SR-IOV devices and updates the list of PCI device specifications.

  • Embeds the host object ID in device specifications.

Nova PCI manager

  • Creates and maintains a device pool with address, vendor ID, product ID, and host ID.

  • Allocates and deallocates PCI devices to instances based on PCI requests.

Nova scheduler

  • Schedules instance placement on hosts that matches the PCI requests


  • Manages hosts in a dedicated compute cluster with NICs and hosts enabled for SR-IOV.

    A separate compute cluster is recommended because DRS rules do not work on devices enabled for SR-IOV.


  • Verify that your deployment is VDS based. SR-IOV does not work with NSX.

  • Requires VMware Integrated OpenStack version 2.0.x or greater.

  • Requires vSphere version 6.0 or greater.