On Monday, February 10th, CloudFlare experienced a large DDoS attack, with nearly 400Gbps of NTP attack traffic hitting our network.
On Monday we mitigated a large DDoS that targeted one of our customers. The attack peaked just shy of 400Gbps. We've seen a handful of other attacks at this scale, but this is the largest attack we've seen that uses NTP amplification.
Over the last couple of weeks you may have been hearing about a new tool in the DDoS arsenal: NTP-based attacks. These have become popular recently and caused trouble for some gaming web sites and service providers.