In Chapter 5, we discussed the minimum requirements for booting an instance in an OpenStack environment:
- A boot source
- A flavor
- An available Neutron network
Neutron allows users to create the necessary virtual resources not only to ensure that their instances obtain internal IP addresses (also known as fixed IPs), but also to have the ability to map external IP addresses (also known as floating IPs) to instances. This allows applications residing in OpenStack instances to be externally accessible. With Neutron, users can view their own networks, subnet, firewall rules, routers, and load balancers, all through the Horizon dashboard, command-line interface, OpenStack SDKs, or directly via the API. Neutron also contains a modular framework powered by a variety of plugins, agents, and drivers, including LinuxBridge and Open vSwitch.