Open Stack

We have been having this issue with devstack installation since Tuesday 6/2.  On trying to add IPv6 address to br-ex, it fails with permission denied.
Here's the output from stack.sh:
+ IPV6_ROUTER_GW_IP=2001:db8::1
+ die_if_not_set 1299 IPV6_ROUTER_GW_IP 'Failure retrieving IPV6_ROUTER_GW_IP'
+ local exitcode=0
++ set +o
++ grep xtrace
+ local 'xtrace=set -o xtrace'
+ set +o xtrace
+ is_neutron_ovs_base_plugin
+ return 0
+ [[ True = \T\r\u\e ]]
++ _neutron_get_ext_gw_interface
++ [[ False == \T\r\u\e ]]
++ sudo ovs-vsctl set Bridge br-ex other_config:disable-in-band=true
++ echo br-ex
+ local ext_gw_interface=br-ex
+ local ipv6_cidr_len=64
+ sudo ip -6 addr add 2001:db8::2/64 dev br-ex
RTNETLINK answers: Permission denied
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.openstack.org/pipermail/openstack-dev/attachments/20150605/c969fd9e/attachment.html>