Oracle provides utilities to enable you to convert your existing single-instance databases to Oracle Real Application Clusters or Oracle RAC One Node databases.
Use the procedures for converting your single-instance database as described in Oracle Real Application Clusters Administration and Deployment Guide. You can convert a single-instance database either to Oracle Real Application Clusters (Oracle RAC), or to Oracle RAC One Node.
For example, you can use RCONFIG to convert your single instance Oracle Database.
Open the template fileConvertToRAC_AdminManaged.xml, and modify it as required for your migration, in accordance with the instructions in the file. Then save the file with a new filename. The information you provide determines how your converted database is configured. The template file is located in the following path:
$ORACLE_HOME/sampleXMLs/ConvertToRAC_AdminManaged.xml
Refer to the section "Converting to Oracle RAC and Oracle RAC One Node from Single-Instance Oracle Databases" in Oracle Real Application Clusters Installation and Configuration Guide for more information.