---
fixes:
  - |
    Updated nova to support os-vif TAP device pre-creation for OVN ports.
    When Neutron sets ``ovs_create_tap`` in vif_details (enabled via
    the ``[ovn]/ovs_create_tap`` config option in the ML2 driver config),
    Nova propagates this to os-vif which creates the TAP
    device before libvirt starts the VM. Nova then configures libvirt with
    ``managed="no"`` so it uses the pre-created TAP device instead of creating
    a new one. This allows nova via os-vif to pre create the tap device in
    pre live migration allowing ovn to install openflow rules before nova
    starts the live migration. This reduces network connectivity downtime
    when ovn is overloaded.

    See `bug 2069718 <https://bugs.launchpad.net/neutron/+bug/2069718>`_.
