Comment 4 for bug 1753540

Reviewed: https://review.openstack.org/550075
Committed: https://git.openstack.org/cgit/openstack/neutron/commit/?id=b07aa19deb82604b954f323a76c70cc623601ca7
Submitter: Zuul
Branch: stable/queens

commit b07aa19deb82604b954f323a76c70cc623601ca7
Author: Daniel Alvarez <email address hidden>
Date: Mon Mar 5 18:05:54 2018 +0100

    Spawn/stop metadata proxies upon adding/deleting router interfaces

    When a network becomes isolated and isolated_metadata_enabled=True, the DHCP
    agent won't spawn the required metadata proxy instance unless the agent gets
    restarted. Similarly, it won't stop them when the network is no longer
    isolated.

    This patch fixes it by updating the isolated metadata proxy on port_update_end
    and port_delete_end methods which are invoked every time a router interface
    port is added, updated or deleted.

    Change-Id: I5c197a5755135357c6465dfe4803019a2ad52c14
    Closes-Bug: #1753540
    Signed-off-by: Daniel Alvarez <email address hidden>
    (cherry picked from 9362d4f1f21df2a27c818bb0c2918241eb67e3d0)