Understanding packet flows in OpenStack Neutron setups

One of the things that confuse people most when dealing with Software Defined Networking (SDN) in OpenStack Neutron are the packet flows.  How do these relate to all the different network interfaces - virtual and physical ones - that Neutron installations typically have? I have written up a summary using some diagrams to help people understand what all the different interfaces are good for. Three examples are given: Internet-bound packets coming from VMs, VM DHCP requests and VM metadata requests. If you have ever asked yourself what br-int, br-tun and br-ex are really good for and how Networking Namespaces and GRE tunnels fit into the OpenStack Neutron networking model, then here is your answer. 

By the way: The material used in these slides is cut right out of our hastexo Academy HX102 class on Networking for OpenStack. If you need to get first-hand knowledge on OpenStack (including topics such as basic knowledge, networking, distributed object storage with Ceph or Swift, High Availability), then our academy is your place to go. Take a look at our schedule to learn more!



Martin, did you forgot to add a link to the slides? Your post gives the impression that you want to show us some great content - but I can't find it.