Description of problem:
There is not connectivity to an external network from an instance when associating a floating IP with pre-created port and launching instance with the port attached.

Version-Release number of selected component (if applicable):
python-neutron-2015.1.0-1.el7ost.noarch
openstack-neutron-2015.1.0-1.el7ost.noarch

How reproducible:

Steps to Reproduce:
1. Create a DVR with internal and external networks

2. Create port associated with the internal network
   # neutron port-create <internal network>

3. Create a floating IP and associate it with the above port
   # neutron floatingip-create <external network>
   # neutron floatingip-associate <floating ip> <port>

4. Launch an instance with the above port attached

5. Verify that the 'fip' namespace is not created on the compute node.
   # ip netns
   # nova boot --flavor <flavor> --image <image-name> --nic port-id=<port> <instance name>

Actual results:
No 'fip' namespace is created 

Expected results:
'fip' namespace should be created and the instance should have connectivity to the external network.

Additional info: