This is how most global load balancing works, and even Google uses systems like this for deciding the closest data center to serve content from (which is why th

This is how most global load balancing works, and even Google uses systems like this for deciding the closest data center to serve content from (which is why they have submitted an internet draft that would add a few octets from the source ip to forwarded dns requests as a solution to this problem.) If you are using a chatty protocol then you can take an early guess as to the closest server based on the dns lookup and then redirect/refine the path once you are actually talking to the endpoint, but in some cases you would take more time re-establishing the connection than you would servicing it from the "wrong" data center so you just grit your teeth and try to either be smarter next time or add the dns server to the "we have no idea where the endpoint is" list. In theory anycast delivery is the right solution, but there is a wide gulf between theory and practicality here. There is a reason that no one uses anycast for anything other than dns at the moment...