Thanks to Tamzin Oscroft for providing this article!
Remote Diagnostic Agent (RDA) is a command line driven, data collection framework that can gather diagnostic information related to Oracle products and their environments to assist in problem diagnosis. Full information on RDA is available in Remote Diagnostic Agent (RDA) – Getting Started (Doc ID 314422.1).
RDA 8.18 includes Healthcheck reports for the 18c database and a new collection for Oracle Traffic Director 12c. This release also includes improvements to the Oracle Internet Directory and Oracle Identity Manager collections as well as an extension of the Oracle Unified Directory (OUD) collection that enables data tracking for target OUD instances created with the WebLogic Scripting Tool (WLST). Complete details for this release are available in RDA Release Notes (Doc ID 414970.1).
This RDA release is bundled with the 2.12.0 release of Diagnostic Assistant (DA). The DA tool is a command line interface framework designed to simplify and standardize the end user’s experience with various diagnostic tools, providing a common lightweight extensible interface to multiple collection tools like ADR, RDA, OCM, and Explorer. DA packages can also work with Oracle applications (JDE EnterpriseOne, Siebel, PeopleSoft) as verifiers, providing a basic Java interface to facilitate the user’s data collection.
For more information about DA functionalities, refer to Diagnostic Assistant: Information Center (Doc ID 201804.2)