When starting Freenet for the first time, the node writes a default configuration file named freenet.ini. You most likely will want to change certain things, like the node-name and the ports on which the node listens for connections.
Changing Settings
The easiest way to change the configuration settings is by using Fproxy.
Configuration Page∞
You can also change configuration settings by manually editing the freenet.ini file.
Note: While some settings can be read "on-the-fly" by Freenet, it is best to stop the node if you want to make any changes manually.