Heroku: HTTP and Git Connectivity Problems
At approximately 03:30 Pacific time, it was determined that Heroku was the target of a distributed denial of service (DDoS) attack. The method of the DDoS was a SYN flood . Our network engineers applied a variety of host-based techniques to reduce the effect of the attacks. A combination of tweaked networking configuration and some quickly built tools for maintaining system firewall rules helped us get the affected servers to the point where they were no longer crashing, but we were still seeing very high levels of network packet loss to the nodes — users often had to reload multiple times in order to get a web page to load.