> On Jun 15, 2015, at 8:00 PM, Randy Bush <ra...@psg.com> wrote: > > dns is udp
15 years ago when we set up 4.2.2.1, there was a fair amount of TCP based DNS. We tried for a bit to support it via the anycast address, but ultimately we decided the support issues weren’t worth it. The few customers that asked/required it were given non-anycast addresses to use for TCP based DNS. I really think the OPs best answer is some DNS based load balancer, that can take metrics based on routing. johno
