Configure OpenStack to use LDAP for identity management

OpenStack is open source software for building public and private clouds that provide an Infrastructure as a Service (IaaS) platform. Keystone is an OpenStack subproject that provides identity services, including user authentication and authorization, for the OpenStack family of projects. This article shows how to configure Keystone to use a Lightweight Directory Access Protocol (LDAP) server as its back end for identity services, instead of the default SQL back end.