zlacker

>>stargr+(OP)
I am no expert by any means. However, I strongly suspect EDNS is not actually needed to run a CDN. There’s a lot of approaches to balancing load and distributing traffic. An example of another approach would be using anycast IPs.

I’m also surprised that traffic from Cloudflare DNS users caused any significant problem. Was it really that much traffic?

>>jchw+64
You could also in theory use the originating IP of the DNS requests themselves. But Cloudfare messes up that as well:

https://twitter.com/archiveis/status/1018691421182791680

> Absence of EDNS and massive mismatch (not only on AS/Country, but even on the continent level) of where DNS and related HTTP requests come from causes so many troubles so I consider EDNS-less requests from Cloudflare as invalid.