The below image is a recommended approach for managing large volumes of traffic coming through your instances. End-user HTTP traffic can be routed through a load balancer, that can then be handed out to the Distributed Front-End Servers. If the front-end server cannot directly service the request, it makes a request to the backend load balancer to handle. The front-end server proxy URL is based on Agent External URL configured on the System Settings page.
A front-end server does not participate in agent communication, workflows, emails, notification services, or cleanup. When connected to a front-end server, you can still do everything that you would be able to do on a normal IBM UrbanCode Deploy server. Requests for services that are not available on a front-end server will proxy a request to the backend.