After you have determined your routing scheme, you can set up the required routes based on the routing rules.
Replication Servers that manage databases containing primary data require direct or indirect routes to the Replication Servers that manage databases with subscriptions for the data.
Replication Servers that manage replicate databases where request functions originate require direct or indirect routes to the Replication Server managing the primary database. If no replicated functions originate in the replicate database, a route from a replicate to a primary Replication Server is not required.
Each route in an indirect route must be a direct route.
You customize function strings for system functions with class scope at the primary Replication Server for the function-string class. In this instance, you must create routes from the primary Replication Server to the Replication Server managing the databases that use the function strings.
See Replication Server Administration Guide Volume 2 > Customize Database Operations > Work with Functions, Function Strings, and Classes > Summary of System Functions > System Functions with Function-string-class Scope.
You customize error classes at the primary Replication Server. In this instance, you must create routes from the primary Replication Server to the Replication Server managing the databases that use the error mappings.
See Replication Server Administration Guide Volume 2 > Handle Errors and Exceptions > Data Server Error Handling > Changing the Primary Replication Server for an Error Class and Replication Server Administration Guide Volume 2 > Customize Database Operations > Manage Function-string Classes > Create a Function-string Class > Primary Site for a Function-string Class.