I believe this is clear in http://docs.openstack.org/diablo/openstack-compute/admin/content/outbound-traffic-flow-with-any-flat-networking.html but the info should also be added to http://docs.openstack.org/diablo/openstack-compute/admin/content/configuring-flat-dhcp-networking.html (found in doc/src/docbkx/openstack-compute-admin/computenetworking.xml).
I believe this is clear in http:// docs.openstack. org/diablo/ openstack- compute/ admin/content/ outbound- traffic- flow-with- any-flat- networking. html but the info should also be added to http:// docs.openstack. org/diablo/ openstack- compute/ admin/content/ configuring- flat-dhcp- networking. html (found in doc/src/ docbkx/ openstack- compute- admin/computene tworking. xml).