--- upgrade: - | Removes the deprecated DHCP provider method ``update_port_address``. For users who created their own network interfaces or DHCP providers the logic should be moved to a custom network interface's ``port_changed`` and ``portgroup_changed`` methods. The following methods should be implemented by custom network interfaces: * ``vif_list``: List attached VIF IDs for a node. * ``vif_attach``: Attach a virtual network interface to a node. * ``vif_detach``: Detach a virtual network interface from a node. * ``port_changed``: Handle any actions required when a port changes. * ``portgroup_changed``: Handle any actions required when a port group changes. * ``get_current_vif``: Return VIF ID attached to port or port group object.