Chapter 5. Switching

In the previous chapter, we learned that users can interact with Neutron in a variety of ways to build virtual networks that connect virtual machine instances to one another and to the network at large. In this chapter, we'll take a closer look at how Neutron implements the virtual network infrastructure to enable the flow of traffic across the cloud.

When users create and connect virtual machine instances to networks, Neutron automatically creates and configures virtual switches on the physical infrastructure nodes. Ordinary users of OpenStack are not exposed to any of the underlying infrastructure, be it physical or virtual, and must rely on the magic of Neutron to ensure traffic gets to where it needs to go. Operators, on the other hand, may have access to the infrastructure and may be asked to troubleshoot issues from time to time. Understanding how Neutron plumbs everything together is a fundamental requirement for operating and supporting OpenStack...