reply to marcelm
Re: [INTERNET] - What to do when you experience a DDoS attack? This is a normal part of Internet life, and you did the right thing by temporarily blocking the replies.
It's likely you weren't even the target, but may have been a unwilling participant in another form of attack, a so called reflected DoS.. where legitimate errors generated by your systems are used against someone else.
I don't know how you're supposed to go about coordinating with Cogeco during attacks, but they need better online presence.. I don't think they ever reply to emails.
In the mean time, you may want to look into implementing rate limiting.. if you haven't already.
Sometimes I'm rude, this is known.