Sonic.net Anycast Name Server Architecture
Sonic.net's primary and secondary name servers are served by two 'DNS Server Plexes' housed at our facilities in Santa Rosa and San Francisco. Either of the two plexes are capable of handling our entire DNS query load. Each of the plexes is designed to operate independently from each other and allows for our name servers to be available in the event that either of the datacenters become isolated from each other or Internet as well enabling non-service-interrupting maintenance and upgrades.
Each of the DNS Server Plexes currently consists of three name servers, a monitoring server, and a hardware load balancer. Two of the name servers are clustered behind the hardware load balancer which monitors the health of each server and distributes requests between them. Additionally, a third server monitors the health of virtual name server provided by the load balancer and announces 220.127.116.11/32 into IBGP providing all services are operational. The third name server stands alone in a different L2 and L3 domain, monitors it's own health and a announces 18.104.22.168/32 and 22.214.171.124/31 into IBGP enabling it to handle queries sent to 126.96.36.199 in the event that the clusters serving 188.8.131.52 are both off-line.
Additionally, there is an idle backup name server that is directly connected to the 184.108.40.206/24 network in Santa Rosa configured to provide name services for both 220.127.116.11 and 18.104.22.168 in the event that there is a systemic failure with the systems used to anycast the server plexes into our network.
The DNS Server Plexes are operated on industry standard Intel servers running Linux and utilize industry standard open source name and route serving software. The monitoring and control software is custom written and maintained in-house.