The document describes how to convert a single instance Oracle database to Oracle Real Application Clusters (RAC) using RMAN. The key steps include:
1. Duplicating the single instance database to an auxiliary instance on the RAC nodes using RMAN DUPLICATE.
2. Configuring the RAC-specific initialization parameters and creating the necessary redo logs and undo tablespaces.
3. Starting instances on each RAC node and registering them with the Cluster Ready Services framework.