Comment 2 for bug 1813540

Reviewed: https://review.openstack.org/634412
Committed: https://git.openstack.org/cgit/openstack/neutron/commit/?id=414bdd4c5997886c97d0e3a0b19c684dafeabb7a
Submitter: Zuul
Branch: master

commit 414bdd4c5997886c97d0e3a0b19c684dafeabb7a
Author: Slawek Kaplonski <email address hidden>
Date: Fri Feb 1 14:42:23 2019 +0100

    Don't specify exactly IP in portforwarding functional test

    In Port Forwarding functional tests, port is created in setUp()
    method. This port had specified exactly IP address and subnet to use.
    This was proposed in [1] to fix issue when new port created in same
    subnet got sometimes IP address outside of subnet range.
    Unfortunatelly that fix was not enough and caused other issues
    as sometimes this "fixed" IP address used for port might be
    used e.g. by router_interface port and that caused sometimes
    "409 conflict" response from Neutron sometimes.

    This patch adds additional method in
    neutron.tests.unit.db.test_db_base_plugin_v2 module to find first
    free IP address from given subnet.
    This method is now used in port forwarding tests module to choose
    IP address for second created port in the subnet so there should be
    no conflicts with IP addresses anymore.

    [1] https://review.openstack.org/#/c/631815

    Change-Id: Iee2f72acf6814a0f8f76d240862429a8b63c3b09
    Closes-bug: #1813540