What should i put in neutron ml2 physical_interface_mappings

I have followed this official tutorial: http://docs.openstack.org/mitaka/install-guide-ubuntu/overview.html

Something does not work with network.

I am not sure i have really understand the meaning of physical_interface_mappings and [vxlan] parameters in linuxbridge_agent.ini file.

Here is my enviroement: I have 2 computers: One for controller and the other for compute (compute1)

Controller gets 2 nic:

• enp0s3: 10.0.0.11 (internal network)
• enp0s8: 192.168.0.11 (external network)

Compute1 gets 2 nic:

• enp0s3: 10.0.0.31 (internal network)
• enp0s8: 192.168.0.31 (external network)

Here is what i put in /etc/neutron/plugins/ml2/linuxbridge_agent.ini on controller machine:

[linux_bridge]
physical_interface_mappings = myexternalnet:enp0s8

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

[vxlan]
enable_vxlan = True
local_ip = 192.168.0.11
l2_population = True

And here is what i put in /etc/neutron/plugins/ml2/linuxbridge_agent.ini on compute1 machine:

[linux_bridge]
physical_interface_mappings = myexternalnet:enp0s3

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

[vxlan]
enable_vxlan = True
local_ip = 10.0.0.31
l2_population = True

myexternalnet is created with this command:

neutron net-create --shared --provider:physical_network provider --provider:network_type flat myexternalnet

neutron subnet-create --name subnet_myexternalnet --allocation-pool start=192.168.20.100,end=192.168.20.200 --dns-nameserver 8.8.4.4 --gateway 192.168.20.1 myexternalnet 192.168.20.0/24

neutron net-update myexternalnet --router:external 

Everything works great, i can create instances but network is not working. I am not sure about physical interface mappings parameters interpretation.

Thanks for your help