You can configure either RemoteServiceName or RemoteServicePort in firebird.conf to override either the default port number (3050) or the default port service name (gds_db) that the server uses to listen for connection requests.

The engine will use one RemoteService* parameter, but not both. If you configure both, it will ignore RemoteServicePort in all cases, except where the server start command was invoked with the -p switch supplying an override to the port service name. Thus, you can use the -p switch and a RemoteService* parameter, in combination, to override both port number and service name.

If the default service name is to be overridden, then you need to make an entry in the Services file.