You can configure a virtual service in CentraSite to configure a virtual service to load balance requests between several service providers without clustering. In this scenario, you create a virtual service that uses a load balancing routing protocol and deploy it to a single instance of Mediator. As service consumers send requests, Mediator distributes messages to several different service provider endpoints that are configured in the VSD. For information about creating a load-balanced virtual service, see CentraSite User’s Guide.

This type of load balancing scenario looks as follows:

When the virtual service is configured using a load balanced routing type, a single Mediator takes requests and routes them to the service providers in turn, using a round-robin distribution. As Mediator receives requests, it distributes the request to the service provider whose turn it is to process the message.

If a service provider endpoint is down when Mediator tries to distribute a request to it, Mediator considers this endpoint inactive. The endpoint remains considered inactive for 60 seconds, during which time all subsequent invocations skip that endpoint and are instead routed to the remaining endpoints.

If all of the endpoints are down, then Mediator considers all of the endpoints inactive for 60 seconds and sends an error event to CentraSite (if enabled).