---
deprecations:
  - The ``network_device_mtu`` option in Nova is deprecated for removal since
    network MTU should be specified when creating the network with
    nova-network. With Neutron networks, the MTU value comes from the
    ``segment_mtu`` configuration option in Neutron.
other:
  - The Neutron network MTU value is now used when plugging virtual interfaces
    in nova-compute. If the value is 0, which is the default value for the
    ``segment_mtu`` configuration option in Neutron before Mitaka, then the
    (deprecated) ``network_device_mtu`` configuration option in Nova is used,
    which defaults to not setting an MTU value.


Add release note for nova using neutron mtu value for vif plugging
Add release note for nova using neutron mtu value for vif plugging

69ec718b62db5766e43552cadfc7b659c7025ba4 changed nova to start using
the network mtu value from neutron (if specified and > 0) when
plugging virtual interfaces. This allows us to finally remove the
deprecated 'network_device_mtu' config option from nova (probably in
Newton).

Add a release note to point out that the segment_mtu value in neutron
is now used to set the mtu value during vif plugging in nova.

Change-Id: Iebffb487cc837427b0ede35aea93ec5f9594165f
Related-Bug: #1549408
