Hi, I need to connect to a db that is in a remote server and I can't connect directly to it, I need to access to that db through a middle server, so my question is: Is possible to configure a listener in a server with no database that redirect's to that db?
Look at Oracle Connection Manager. It does what you describe.
All requests go to the OCM listener, and OCM then talks to the database listener. Optionally, you can use OCM as a concentrator, multiplexor, multi-protocol integrator, and a firewall. However, it takes most people more than a day to setup.