Introduction

OpenStack Networking is the Software Defined Networking (SDN) component of OpenStack and its project name is Neutron. With SDN, we can describe complex networks in a secure multitenant environment that overcomes the issues often associated with the Flat and VLAN OpenStack networks. In OpenStack, SDN is a pluggable architecture, which means we are able to plug in and control various switches, firewalls, and load balancers and achieve various functions such as Firewall-as-a-Service. All this is defined in software to give you fine-grained control over your complete cloud infrastructure.

OpenStack Networking is a replacement for the networking component that is available with OpenStack Compute itself: nova-network. While nova-network is still seen as more robust and available for use, many people are deploying OpenStack Networking in production. Nova-network is expected to be deprecated in an upcoming release of OpenStack.

The following figure shows the OpenStack architecture as described in this chapter.

In this environment, we have a Controller, a Network host, and one or more Compute hosts. The hosts are all running Ubuntu 14.04 and have a number of network cards installed as shown in the figure. For the purpose of this chapter, we reference the virtual environment that accompanies the text and as such an interface eth0 is dedicated to the out-of-band management for the environment itself. Therefore, it remains unassigned. As you begin to work with OpenStack in a production environment, the networking requirements will likely vary, and will need to change the interface assignments.

For consistency of network configuration, each interface has a dedicated network associated with it. This is described in the following table: