---
prelude: |
    The 24.0.0 release includes many new features and bug fixes. Please be
    sure to read the upgrade section which describes the required actions to
    upgrade your cloud from 23.0.0 (Wallaby) to 24.0.0 (Xena).

    There are a few major changes worth mentioning. This is not an exhaustive
    list:

    - The latest Compute API microversion supported for Xena is v2.90.
      Details on REST API microversions added since the 23.0.0 Wallaby release
      can be found in the `REST API Version History`__ page.

      .. __: https://docs.openstack.org/nova/latest/reference/api-microversion-history.html

    - `Support for accelerators`__ in Nova servers has been improved. Now
      Cyborg-managed SmartNICs can be attached as SR-IOV devices.

      .. __: https://docs.openstack.org/api-guide/compute/accelerator-support.html


    - Two new ``nova-manage`` CLI commands can be used for `checking`__ the
      volume attachment connection information and for `refreshing`__ it if the
      connection is stale (for example with a Ceph backing store and MON IP
      addresses). Some documentation on how to use them can be found `here`__.

      .. __: https://docs.openstack.org/nova/latest/cli/nova-manage.html#volume-attachment-get-connector
      .. __: https://docs.openstack.org/nova/latest/cli/nova-manage.html#volume-attachment-refresh
      .. __: https://docs.openstack.org/nova/latest/admin/manage-volumes.html#managing-volume-attachments

    - Instance hostnames published by the metadata API service or config drives
      can be explicitly defined at instance creation time thanks to the new
      `2.90 API microversion`__. See the ``hostname`` field documentation on
      the `API docs`__ for further details.

      .. __: https://docs.openstack.org/nova/latest/reference/api-microversion-history.html#maximum-in-xena
      .. __: https://docs.openstack.org/api-ref/compute/?expanded=create-server-detail#create-server

    - Libvirt virt driver now supports any PCI device, not just virtual
      GPUs, that are using the ``VFIO-mdev`` virtualization framework, like
      network adapters or compute accelerators. `See more in the spec`__.

      .. __: https://specs.openstack.org/openstack/nova-specs/specs/xena/approved/generic-mdevs.html

Add the Xena prelude section
Add the Xena prelude section

Coming straight from the cycle highlights.

Change-Id: I40f1962e978bec23bfc5018001efc02317acb861
