In this chapter, we looked at some basic network architectures found in many OpenStack clouds that utilize Neutron networking. For performance and simplicity in operations and troubleshooting, many users find connecting instances directly to provider networks the best option when available. For users who want to have a hand in the overall network architecture in order to meet complex network requirements, using tenant networks and Neutron routers provides features and functionality above and beyond what provider networks alone can do. Not to mention, Neutron routers are a requirement for advanced Neutron services, such as Firewall as a Service, Load Balancer as a Service, and VPN as a Service in a reference implementation. When building a network architecture to support your application, try drawing a logical diagram similar to the ones pictured in this chapter to get a good idea of traffic flow between networks and instances before implementing the networks in Neutron.
In the next...