Comment 30 for bug 1933092

Reviewed: https://review.opendev.org/c/openstack/neutron/+/807244
Committed: https://opendev.org/openstack/neutron/commit/c689ac5a661a15ec7ad1098d21dc5affce97fb04
Submitter: "Zuul (22348)"
Branch: stable/train

commit c689ac5a661a15ec7ad1098d21dc5affce97fb04
Author: Hemanth Nakkina <email address hidden>
Date: Fri Jul 2 17:01:55 2021 +0530

    Update arp entry of snat port on qrouter ns

    In some cases, the arp entry of snat port is not updated
    in qrouter namespace. l3-agent calls get_ports_by_subnet()
    while setting arps for the subnet. And the snat port is
    not returned if it is still unbound. One of the scenario
    this is observed is when router is created, external
    gateway set and internal subnet attached to router in
    quick succession.

    This patch retrieves snat port details from router info
    as well and updates arp entry for snat port.

    Conflicts:
        neutron/agent/l3/dvr_local_router.py

    Closes-Bug: #1933092
    Change-Id: I7ee797b4b930306cf6360922d855f8b24f1b813d
    (cherry picked from commit be7d0bb6abc893e53dfc864c52506928b1d38fa3)
    (cherry picked from commit f1a9f4ed62fd2567cac174f80f87de53148ea7b9)