---
features:
  - |
    The nova Hyper-V driver now supports adding PCI passthrough devices to
    Hyper-V instances (discrete device assignment). This feature has been
    introduced in Windows / Hyper-V Server 2016 and offers the possibility to
    attach some of the host's PCI devices (e.g.: GPU devices) directly to
    Hyper-V instances.
    In order to benefit from this feature, Hyper-V compute nodes must support
    SR-IOV and must have assignable PCI devices. This can easily be checked by
    running the following powershell commands::

        Start-BitsTransfer https://raw.githubusercontent.com/Microsoft/Virtualization-Documentation/master/hyperv-samples/benarm-powershell/DDA/survey-dda.ps1
        .\survey-dda.ps1

    The script above will print a list of assignable PCI devices available on
    the host, and if the host supports SR-IOV.

    If the host supports this feature and it has at least an assignable PCI
    device, the host must be configured to allow those PCI devices to be
    assigned to VMs. For information on how to do this, follow this guide [1].

    After the compute nodes have been configured, the nova-api, nova-scheduler,
    and the nova-compute services will have to be configured next [2].

    [1] https://blogs.technet.microsoft.com/heyscriptingguy/2016/07/14/passing-through-devices-to-hyper-v-vms-by-using-discrete-device-assignment/
    [2] http://docs.openstack.org/admin-guide/compute-pci-passthrough.html
