Hi, folks, Now the neutron use a random function to generate the mac address for neutron port when it was created . The sequence is as follow: _generate_mac get_random_mac random.randint As i understand it, it is possible to get same mac when create two different port. Because the random is pseudo random, not a fixed based on some unique base. Can anyone give me some explain? Thanks -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.openstack.org/pipermail/openstack-dev/attachments/20160728/65573968/attachment.html>