Core role configuration overview
Core roles have a shared configuration framework that allow you to:
Define a server role or a supported combination of server roles. For example, a single Core role instance can act as an xDB Processing role or a combination of Content Management, xDB Processing, and xDB Reporting.
Use rule-based configuration to switch your own configuration on and off depending on the context role.
Patch configuration changes instead of modifying the default configuration files.
Use the showconfig.aspx tool to see what the final compiled configuration looks like per role.