Chapter 1. Introduction

Red Hat OpenStack Platform director creates a cloud environment called the Overcloud. The Overcloud contains a set of different node types that perform certain roles. One of these node types is the Controller node. The Controller is responsible for Overcloud administration and uses specific OpenStack components. An Overcloud uses multiple Controllers together as a high availability cluster, which ensures maximum operational performance for your OpenStack services. In addition, the cluster provides load balancing for access to the OpenStack services, which evenly distributes traffic to the Controller nodes and reduces server overload for each node.

It is also possible to use an external load balancer to perform this distribution. For example, an organization might use their own hardware-based load balancer to handle traffic distribution to the Controller nodes. This guide provides the necessary details to help define the configuration for both an external load balancer and the Overcloud creation. This involved the following process: