[Gibins]

As far as developing the server, it's just an apache server I made in the vps I host the game from. It's running ubuntu.

apt install apache2
systemct1 enable apache2
systeamct2 start apache2
Set the sv_downloadip to the one I posted earlier

I don't think it's misconfigured or needed permissions because I've hosted a killing floor server until recently and currently host Quake3 servers on this same vps and their fast downloads worked perfectly fine.

With that final dash on the "http://IP/cstrike" it's there in my config and it still works. It wouldn't surprise me if it made a difference and for some reason caused the fast dl to not work on someone else's server though. I swapped between using no dash at the end or using the dash at the end in my many attempts at this before, so it was a variable I was keeping in mind.

It's honestly wild that it just began working and I have no idea why. I restarted the vps multiple times over the course of working on it, no luck. I restarted my computer, no luck. Tried a bunch of different configs and cvar combinations, no luck. But then I wake up one morning and try it, just happening to use the "developer 1" command, now it works... very cool.

As far as what fysiks said about using the steamcmd version, I set up another HLDS using the version from steamcmd like they recommended and the fast download works just fine. The developer.valvesoftware page on HLDS says to use ReHLDS since it's more secure and has bugfixes, so I apply that to the steamcmd version, fastdl still works fine. I honestly have no idea what the holdup was before. Not like I'm amazing at setting up game servers, but I've done it for quite a few games, so the whole time I was just thinking "I swear I'm doing this correctly. Why doesn't it work?" Just for it to begin working after I change nothing.