The answer to "will the game server try to send the client the files manually" is "no".
Spoiler
Say I have a Source server that has sv_downloadurl set to a fastdl server, and that everything is configured properly. The fastdl server is separate from the game server.
I want to use Late Downloads to create a file while players are playing, send it to them, then add it to the downloads table so anyone who joins afterwards downloads the file and precaches it. The files are very small, about 350 bytes uncompressed.
If I do not copy the files to the fastdl server, will the game server try to send the client the files manually after the fastdl server fails to send the file?
The files in question are VMT files. They will be generated the moment the client requests them, and will be precached as soon as all connected clients have received the file. Since they will be made dynamically, I cannot preemptively add them to the fastdl server.
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