I'm only calling it "trickery" because DNS isn't supposed to work that way. The entire systems structure of authoritative resolvers to recursive resolvers to ca

I'm only calling it "trickery" because DNS isn't supposed to work that way. The entire systems structure of authoritative resolvers to recursive resolvers to cachers depends on a record being the same regardless of external factors like location or source IP. Meanwhile, anycast was literally designed for this purpose. And it's been around since 1993.[1] >explain how anycast works Advertise your IP space in multiple locations. Traffic will come to the location closest[2] to it. There's nothing particularly complicated about it. How the routing end of it works is up to the specific protocol you're using and whether this is external or internal... so it depends on BGP on the Internet (in the case we're talking about here), but you can also anycast on your internal network, and the routing will be handled by OSPF/IS-IS/whatever. Further, effectively every large service online today uses anycast clusters. Do you think 8.8.8.8 goes to a single server? Cloudflare IPs? Google IPs? It's all anycast. [1]https://tools.ietf.org/html/rfc1546 https://tools.ietf.org/html/rfc1546 [2]"closest" is subjective, it's not necessarily the geographically closest, but the "best" path. This is decided by the specific protocol you're using, but generally you can assign costs/metrics to various routes to prioritize/deprioritize them. This is your netops team's problem, not yours, so for all intents and purposes you'll always get the "best" path.