Recently, my TF2 server has been a target of many DDoS attacks, in fact once a day for the past 4 consecutive days as soon as my server starts filling. Before the most recent one I installed the DDoS Attack Fixer Plugin. It must have been properly installed because it shows up when I use the plugin_print command, as well as the daf_status command in console. Despite this, another successful DDoS attack plagued my server today (causing an immense amount of lag for a while before the eventual crash). When my server came back up hours later, I checked the daf_status to see if it at least caught an IP, but not only did it not prevent the attack, it also didn't log any banned IP's.
Is this a common issue? One would assume that due to all of this, it isn't even a DDoS. My service provider, counter-strike.com, informed me and insisted that it was, in fact, a DDoS attack every time (though saying they couldn't do anything about it). It also seems likely due to my new server having broken off from my old server, from which I took many regulars (it could be one of them getting revenge) and the fact that it only occurs when my server starts to fill (it works fine in a 7v7-8v8+ environment for a while, then starts to screw up).