In the few days since launching my Global DNS Tester, I've made a few significant improvements. It's no longer limited to looking up A records alone; you can now compare A, AAAA, PTR, CNAME, NS, MX, and SOA records returned for any given host/IP from up to 100 public nameservers simultaneously.
I've also made a bunch of iterative improvements to the interface, and some minor performance improvements.
If you have any feedback or suggestions, feel free to leave a comment or e-mail me!
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