Applications may use and modify customer's domain in PA. For example, being installed on a domain, externally hosted applications may create additional DNS records, pointing to an external multi-tenant server, in the domain and propagate the domain into a correspondent tenant of the application, see DNS Zone in for details. Shared and VPS hosting applications can get domain name by URL Mapping declaration. For externally hosted applications containing no URL mapping, PA defines the setting with a special class, see Service Settings, Data Types for details.