Per suggestion of Stat Development:
You can only configure object types for servers where Oracle agent is running on. If this is an Oracle Ebusiness environment that you are configuring, you could have different nodes on different servers. If the instance does not use a shared appl top, then you need to have a separate agent running on each node.
In Stat you configure different nodes in ‘Server’ maintenance of the Oracle Application Maintenance. There is usually just one Admin server, but you may have a number of Web/Forms/Concurrent manager servers.
As far as OA Generic vs Custom object type, we encourage using custom, because it is a lot less configuration.
I also want to make sure you understand that if we are talking about a web server outside of Oracle ebusiness environment, then you might be looking at Generic Apps environment. In this case, Central agent may be used to copy files from one environment to another.