The Reseller project model extends hierarchical multitenancy (HMT) by treating domains as top-level projects, so that you can subdivide your cloud into domain hierarchies for delegated administration or resale.

Reseller (phase 1) merges domains into the project table. Previously, Identity service (keystone) domains were containers that stored users and projects in their own database table. Domains are now a type of project, which enables hierarchical organization:

• A domain is now a type of project, distinguished by the is_domain flag.
• A domain represents a top-level project in the project hierarchy: domains are roots in the project hierarchy
• APIs have been updated to create and retrieve domains using the projects subpath:
  • Create a new domain by creating a project with the is_domain flag set to true
  • List projects that are domains: get projects including the is_domain query parameter.