I doubt it's that easy to solve a DDoS. Considering the downtime, this DDoS is well organised, possible using hundreds of infected PCs as hosts to carry out the attack. The simple solution would be to start blocking IPs, but that would probably mean blocking out some players in some cases. Again considering the downtime, at this point the DDoS is either sabotage or ransom. At work, I had to go through this multiple times unfortunately. When the attackers are good and have a big enough network it's very hard to stop them.