OpenStack supports a multi-tenancy model. The latter naming convention of Tenant in OpenStack is transformed to Project. As discussed in Chapter 3, OpenStack Cluster - The Cloud Controller and Common Services, Keystone is the OpenStack component that manages access to resources by grouping and isolating them by a defined project or tenant. This means that any user or newly created user group can have access to a given project. To permit a user access to a certain number of predefined sets of resources is ensured by assigning roles. The role concept in OpenStack denotes which service or group of services a user is authorized to have access to.
In a real production OpenStack environment, several users would need to access several types of services and have a certain liberty to exploit their underlying resources. As an OpenStack administrator, you should be able to denote the hierarchy...