Ondřej and I had a brief discussion over Twitter a few weeks ago about some of the DNS Spy scores related to using a single domain in your name servers vs. spreading the risk across multiple domains.
He wrote an excellent follow-up to further clarify his point, and I can only agree with him.
I’ll be reviewing the scoring system accordingly.
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It took us full 20 full DNS queries to resolve example.udp53.cz domain name, and even if the DNS Resolver would pick the optimal path on every step, we would still end up with 8 queries.
Source: Are homogenic nameserver names a single point of failure?