I just came across the Amin Blogs post "
Registering non-default XMLDB HTTP/WebDAV and FTP ports on a non-default Oracle Listener port" on http://www.orablogs.com - (broken link) orablogs. This post by Marco Gralike talks in details about setting up two listeners on a server that is pretty busy. He talks about having two different version listeners running on the same machine. Marco gives some technical details and examples of how to setup and start two listeners. I find this a good example as people ask me from time to time about setting up two listeners for one database with the intention that one of those listeners is specifically to run
extproc from. This is so that even if the listener is compromised via
extproc that the server is in less danger from hackers as the account they would have captured should have no server privileges or access.
Marco starts his short article with some discussion of creating and setting up two listeners and shows some examples. He works through the set up and shows how to start both and how to check that they are running. He then talks in detail about registering the database with the correct listener. Then Marco talks about the use of the LOCAL_LISTENER parameter in the init.ora in 10g so that the 10g database will register itself with the correct listener. This is an interesting discussion that goes on to talk about the XMLDB daemons. Marco then talks about registering the FTP and WebDAV and HTTP on different ports showing examples and details of how to do this including alerting the ports.