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Stéphane Bortzmeyer
With my Unbound resolver, I get results similar to yours but with Google Public DNS, it's more fun: https://framapic.org/HpnX0WIfdiMl/An1vwwGtuDXb.png Google handles GOST DS but not GOST signatures. Also, it SERVFAILs for RSA-MD5 signatures.