On the network node (neutron) after creating the br-ex bridge and attaching it to a port on the physical network, one might lose internet connectivity. The network node will no longer be able to ping the tenant gateway router. So we can still create and launch instances but they might not have access to the internet.
One fix is to update the /etc/network/interfaces file by setting a static ip on the external network for the br-ex interface followed by ifdown br-ex && ifup br-ex. Now the network node can access the tenant-gateway-router. It would be good to have this on the official documentation, there are bits and pieces of this info scattered across the internet . It took me some time to understand this.
Also if one restarts the controller node, the nova-services do not restart. So one has to place a suitable script either in rc.local or elsewhere to make sure these restart as well.
I just felt this information could be useful to others like me.
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Built: 2015-02-26T08:12:57 00:00
git SHA: f4b8c7519d7bcd7d03316ccd31f7557afb92f0aa
URL: http://docs.openstack.org/juno/install-guide/install/apt/content/neutron-network-node.html
source File: file:/home/jenkins/workspace/openstack-manuals-tox-doc-publishdocs/doc/install-guide/section_neutron-network-node.xml
xml:id: neutron-network-node
Could go in install guide or networking guide.