Server got attacked by DDoS: Where to report?

Short story: Guy changes name, logs in, asks for server ip (for his girlfriend, supposedly), logs out, changes name back, server gets DDoS’d, publicity to the guy’s server starts popping up.

The evidence is clear, and there are screenshots for a very strong case.
My only question is where should I report him? These forums, steam forums or on his profile’s report button?

Thank you in advance

[editline]29th August 2015[/editline]

Alright, since people seem to be thinking this was a joke post, can you at least tell me if this is done by any legal server-side mod?
http://images.akamai.steamusercontent.com/ugc/434949660514752825/6CA8EA034F198EC42069C4F719E269FC43C22544/

Nothing anyone can do here if your network can’t prevent a denial of service attack. If that’s actually what even happened.

Not my server, therefore not my network either. But between eyewitnesses (of IP request, unusual lag and server publicity, in this order), and screenshots of one of the involved parties being the admin of the publicized server, shouldn’t that be a strong enough case? I really only need to know the correct place to send this info to.

Regarding the screenshot (yes, from the same player), is it a clear wallhack or is it some legal mod I don’t know about?

It’s a game dude, just report it to Steam and watch it be ignored.

DDOS cannot be reported in a sense that nothing can be done so no one cares.
As for the screenshot, it’s wallhack. Serverside mods currently cannot change clientside graphics.

Thank you, that should send him on another VACation (yes, he does already have one on record). Already reported the picture and took a screenie in case he realizes his own stupidity and deletes it.

No, it won’t…