Did you follow the guides on http://docs.openstack.org/mitaka/install-guide-ubuntu/launch-instance.html (this page) under the 'Create virtual networks' header? It shows how to create the provider and self service network.

I've done this, and I'm in the same boat as you unfortunately - new install of Mitaka and have no external network access.

hi guys , i am also new t openstack i am trying to deploy openstack on two nodes that is controller and compute bt i am confused, the provider network that is external we are not setting any ip to it so how does it works does it occupies ip through our physical network dhcp ?

thank ou replying for our answers .

To create external network, there are two scenarios as described in the installation manual.
I assume that Scenario-2 and flat network (Because scenario-1 is not flexible) and use Linux bridge.
First edit the /etc/neutron/plugins/ml2/ml2_conf.ini as described in manual, especially set:

[ml2_type_flat]
flat_networks = provider

And also specify in /etc/neutron/plugins/ml2/linuxbridge_agent.ini:

[linux_bridge]
physical_interface_mappings = provider:em2    # em2 = interface name facing to external network

After configure and start neutron and related service, execute the following command with admin privilege:

$ source admin-openrc
$ neutron net-create ext-net --router:external \
 --provider:physical_network provider --provider:network_type flat \
 --shared

$ neutron subnet-create ext-net --name ext-subnet \
  --allocation-pool start=10.102.24.120,end=10.102.24.130 \
  --disable-dhcp --gateway 10.102.24.0.1 10.102.24.0/24

Then move to demo project (it is also possible to stay in admin if you like).

$ source demo-openrc 
$ neutron net-create Private
$ neutron subnet-create Private 10.0.0.0/24 \
   --name Private-subnet --gateway 10.0.0.1 --dns-nameserver 8.8.8.8   #<= your DNS server address

$ neutron router-create ext-router
$ neutron router-gateway-set ext-router ext-net
$ neutron router-interface-add ext-router Private-subnet
$ neutron router-show ext-router   # <= you can see external ip address assigned to ext-router

ping to external ip address of ext-router to verify connectivity.