The RESTful API method used to retrieve an existing configuration from an XtremIO system is the HTTP GET methD. This is a standard method used in RESTful APIs for retrieving resources. In the context of XtremIO, the GET method would be used to call endpoints that return information about the system's configuration. For example, a GET request to /api/json/v2/types/clusters would retrieve information about the clusters1. The Official Dell XtremIO Deploy Achievement document will contain specific details on the API calls and should be referred to for the most accurate instructions.