---
prelude: |
    The 17.0.0 release includes many new features and bug fixes. It is
    difficult to cover all the changes that have been introduced. Please at
    least read the upgrade section which describes the required actions to
    upgrade your cloud from 16.0.0 (Pike) to 17.0.0 (Queens).

    That said, a few major changes are worth mentioning. This is not an
    exhaustive list:

    - The latest Compute API microversion supported for Queens is v2.60. Details
      on REST API microversions added since the 16.0.0 Pike release can be
      found in the `REST API Version History`_ page.
    - The placement service should be upgraded before the nova controller and
      compute services. See the `Pike Upgrade Notes for Queens`_ for more
      details.
    - Some of the `multi-cell cells v2 caveats`_ have been resolved.
    - Cells v1 and nova-network continue to be deprecated, and plan to be
      removed in the 18.0.0 Rocky release.
    - The libvirt and xenapi compute drivers now have (experimental) native
      support for virtual GPU devices. See the `virtual GPU`_ admin guide for
      more details.
    - The libvirt compute driver now supports volume multi-attach when using
      the 2.60 compute API microversion. See the cinder admin guide for more
      details about volume multi-attach support in OpenStack.
    - Version 1.0.0 of the `osc-placement plugin`_ has been released which
      provides CLI support for interacting directly with the Placement API.
    - Traits-based scheduling is now available for the ironic compute driver.
      For more details, see the `ironic docs for scheduling based on traits`_.

    .. _REST API Version History: https://docs.openstack.org/nova/latest/reference/api-microversion-history.html

    .. _Pike Upgrade Notes for Queens: https://docs.openstack.org/nova/latest/user/placement.html#queens-17-0-0

    .. _multi-cell cells v2 caveats: https://docs.openstack.org/nova/latest/user/cellsv2-layout.html#caveats-of-a-multi-cell-deployment

    .. _virtual GPU: https://docs.openstack.org/nova/latest/admin/virtual-gpu.html

    .. _osc-placement plugin: https://docs.openstack.org/osc-placement/latest/index.html

    .. _ironic docs for scheduling based on traits: https://docs.openstack.org/ironic/latest/install/configure-nova-flavors.html#scheduling-based-on-traits