Update: 4:15pm – Today at 12:28pm Sonic experienced a network instability event of an unknown origin at the time. Through troubleshooting we were able to narrow down the issue to two transport links going from one of our datacenter locations to core network equipment. These links were receiving replicated traffic from the transport providers network equipment, sent back at us. The replicated traffic overloaded the CPU on our core routers. We have taken steps to prevent the replicated traffic from affecting our network, and we have contacted our provider for further diagnosis. Apologies for the delay in getting issue resolved, it was a very difficult problem to troubleshoot, and we have never seen anything like this happen before.
Update 3:42pm – We believe everything is restored. We will release a RFO soon with more specific information.
Update 2:46pm – We are still working to mitigate the DoS. All of our engineering staff is currently engaged in this issue. We will post more details as they become available.
As of 12:30pm, the Sonic network is experiencing reachability issues to the outside world. A large DoS attack is the suspected cause but we are still working to identify and mitigate the problem ASAP. More information will follow.