Comment 2 for bug 1265081

Reviewed: https://review.openstack.org/64554
Committed: https://git.openstack.org/cgit/openstack/neutron/commit/?id=de4b5a2bba57cbd5294fb6f9527d64b8eeddf901
Submitter: Jenkins
Branch: master

commit de4b5a2bba57cbd5294fb6f9527d64b8eeddf901
Author: armando-migliaccio <email address hidden>
Date: Tue Dec 31 05:51:43 2013 -0800

    nicira: fix db integrity error during port deletion

    Due to the fact that plugin port operations are not
    transactional (as they involve non synchronized DB
    and Controller operations), concurrent (interleaved)
    port requests may accidentally cause the insertion
    of the mapping entry (neutron-port-id, nvp-port-id)
    more than once. In case this occurs, it's safe to
    expect the failure and continue the normal process
    of the operation being requested.

    Closes-bug: #1265081

    Change-Id: Ifcf5b453fa08145df844c2de3cbb08bf2f4baa59