A fast download server (fastdl) is a webserver that hosts the downloadable game server files, such as maps or models. Being hosted on a webserver allows a person to download the content much more quickly than a direct download from the server and also doesn't use up the server's bandwidth with file transfers.
First things first, you will need a webserver. I recommend Appache
. Installation will vary depending on what operating system you are running, so google around for a tutorial. I recommend a query similar to "how to install apache on [my operating system]". There are usually tons of tutorials to choose from.
Once you've got the webserver up, you need to set up the folder structure exactly like it is in your cstrike, czero, dod, other game folder. For example, on my counter strike server, inside the directory cstrike, there are a number of folders: maps, models, sounds, etc. Your fastdl web address needs to mirror the cstrike folder.
For example, let's say your web server's address is myfastdl.com. Inside your cstrike folder, there is a maps folder; so inside myfastdl.com there needs to be a maps directory, myfastdl.com/maps.
You only need to upload files that would be downloaded from the server. Sounds, models, maps, wad files, and map overviews are examples. You do NOT need to upload things like server config files, core game files (like dlls), bot navigation files, or the addons folder.
Once you have all the files on the fastdl server, you need to add a line to your server.cfg file to tell the server "If somebody needs a file, go to myfastdl.com to download it." This is the line you need to add: