We've bike-sheded over this before
(I5252a12223a35f7fb7a4ac3c58aa4a3cd1bc4799) but I have just traced
down further issues to firewalld with neutron+ipv6 (see the bug).
In fact, as mentioned in the comments, RDO disables firewalld and the
neutron guide says to disable it [1]. The force flag is left if
anyone really wants this; but nobody is testing (or, as far as I can
tell, working on) this so bring devstack back into line and disable it
always. Note we do not remove the package; as has been found in the
puppet scripts this can lead to dependency issues.
[1] http://docs.openstack.org/developer/devstack/guides/neutron.html
Change-Id: Ief7cb33d926a9538f4eb39c74d906ee0c879de35
Partial-Bug: 1455303
3380a16974