Yes, exactly, but you also need to have the map in you're own source dedicated folder
I hope you have good internet, because it really chews you're internet.
I just suggest buy a gameserver at gameservers.com or darkstarllc.com
They're cheap and good
If you've got a reasonably fast cable line (say 6 to 8 megabits) then there should be no issues in hosting about 16 players. Unless you're on FIOS you won't be looking at 24 though.
If you want to use a redirect, simply upload the compressed map files (bz2 format) to your website and in the server.cfg file add the command
sv_downloadurl "http://www.yoursite/.../tf/"
The [...] is whatever happens to be between your website homepage and the /tf/ folder. Think of it the same way as your own copy on your desktop is setup. You *must* point the sv_downloadurl to that /tf/ folder though, because it isn't made just for maps.
Shouldn't this thread be in the server discussion board? :
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