Hello I have trouble installing liberty on ubuntu following the openstack guide,using Networking Option 1: Provider networks

On the controller:
Linux bridge agent is failing with 'LinuxBridgeNeutronAgentRPC' object has no attribute 'state_rpc'

/etc/neutron/plugins/ml2/ml2_conf.ini

[ml2]
type_drivers = flat,vlan
tenant_network_types =
mechanism_drivers = linuxbridge
extension_drivers = port_security

[ml2_type_flat]
flat_networks = public

[ml2_type_vlan]

[ml2_type_gre]

[ml2_type_vxlan]

[ml2_type_geneve]

[securitygroup]
enable_ipset = True

/etc/neutron/plugins/ml2/linuxbridge_agent.ini

[linux_bridge]
physical_interface_mappings = public:em2

[vxlan]
enable_vxlan = False

[agent]
prevent_arp_spoofing = True

[securitygroup]
enable_security_group = True
firewall_driver = neutron.agent.linux.iptables_firewall.IptablesFirewallDriver

cat neutron-plugin-linuxbridge-agent.log

2016-01-27 10:07:14.501 28707 CRITICAL neutron [-] AttributeError: 'LinuxBridgeNeutronAgentRPC' object has no attribute 'state_rpc'
2016-01-27 10:07:14.501 28707 ERROR neutron Traceback (most recent call last):
2016-01-27 10:07:14.501 28707 ERROR neutron   File "/usr/bin/neutron-linuxbridge-agent", line 10, in <module>
2016-01-27 10:07:14.501 28707 ERROR neutron     sys.exit(main())
2016-01-27 10:07:14.501 28707 ERROR neutron   File "/usr/lib/python2.7/dist-packages/neutron/plugins/ml2/drivers/linuxbridge/agent/linuxbridge_neutron_agent.py", line 1158, in main
2016-01-27 10:07:14.501 28707 ERROR neutron     launcher.wait()
2016-01-27 10:07:14.501 28707 ERROR neutron   File "/usr/lib/python2.7/dist-packages/oslo_service/service.py", line 281, in wait
2016-01-27 10:07:14.501 28707 ERROR neutron     status, signo = self._wait_for_exit_or_signal(ready_callback)
2016-01-27 10:07:14.501 28707 ERROR neutron   File "/usr/lib/python2.7/dist-packages/oslo_service/service.py", line 268, in _wait_for_exit_or_signal
2016-01-27 10:07:14.501 28707 ERROR neutron     self.stop()
2016-01-27 10:07:14.501 28707 ERROR neutron   File "/usr/lib/python2.7/dist-packages/oslo_service/service.py", line 196, in stop
2016-01-27 10:07:14.501 28707 ERROR neutron     self.services.stop()
2016-01-27 10:07:14.501 28707 ERROR neutron   File "/usr/lib/python2.7/dist-packages/oslo_service/service.py", line 612, in stop
2016-01-27 10:07:14.501 28707 ERROR neutron     service.stop()
2016-01-27 10:07:14.501 28707 ERROR neutron   File "/usr/lib/python2.7/dist-packages/neutron/plugins/ml2/drivers/linuxbridge/agent/linuxbridge_neutron_agent.py", line 882, in stop
2016-01-27 10:07:14.501 28707 ERROR neutron     self.set_rpc_timeout(self.quitting_rpc_timeout)
2016-01-27 10:07:14.501 28707 ERROR neutron   File "/usr/lib/python2.7/dist-packages/neutron/plugins/ml2/drivers/linuxbridge/agent/linuxbridge_neutron_agent.py", line 1124, in set_rpc_timeout
2016-01-27 10:07:14.501 28707 ERROR neutron     self.state_rpc):
2016-01-27 10:07:14.501 28707 ERROR neutron AttributeError: 'LinuxBridgeNeutronAgentRPC' object has no attribute 'state_rpc'
2016-01-27 10:07:14.501 28707 ERROR neutron
2016-01-27 10:07:15.142 29877 INFO neutron.common.config [-] Logging enabled!
2016-01-27 10:07:15.143 29877 INFO neutron.common.config [-] /usr/bin/neutron-linuxbridge-agent version 7.0.0
2016-01-27 10:07:15.143 29877 INFO neutron.plugins.ml2.drivers.linuxbridge.agent.linuxbridge_neutron_agent [-] Interface mappings: {'public': 'em2'}
2016-01-27 10:07:15.144 29877 INFO neutron.plugins.ml2.drivers.linuxbridge.agent.linuxbridge_neutron_agent [-] Bridge mappings: {}
2016-01-27 10:07:15.144 29877 INFO neutron.plugins.ml2.drivers.linuxbridge.agent.linuxbridge_neutron_agent [-] Agent initialized successfully, now running...
2016-01-27 10:07:15.182 29877 ERROR neutron.agent.linux.utils [req-1ed1f07e-e6dd-4162-ab92-744b5ecc54f3 - - - - -]

root@:/etc/network# cat ...