Comment 12 for bug 1655567

Reviewed: https://review.openstack.org/469669
Committed: https://git.openstack.org/cgit/openstack/neutron/commit/?id=802cf1194218dc125b7211d9c48df8cfebd4f932
Submitter: Jenkins
Branch: master

commit 802cf1194218dc125b7211d9c48df8cfebd4f932
Author: Miguel Lavalle <email address hidden>
Date: Wed May 31 16:38:57 2017 -0500

    Fix race between create subnet and port requests

    When creating an IPv6 auto-address subnet for a network, ports can be
    created or updated concurrently in the same network, before the subnet
    creation concludes. In such a situation, an IpAddressAlreadyAllocated
    exception may be raised, because the subnet create request attempts to
    allocate auto addresses to the concurrently created or updated ports,
    which have been already allocated by the port requests.

    This patchset adds code to the IPAM to skip the attempt to assign the
    auto address to ports if they already have received them.

    Change-Id: If1eb4046865f43b15ba97c52e2d0b9343dc72c19
    Closes-Bug: #1655567