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A comment on Some ways DNS can break. Parent comment

Re:Some ways DNS can break by tinus_hn on Monday January 17, 2022 @06:29AM (#29965514)
I remember when you could list entire cctlds, how did that work then? They weren’t as big as they are today but definitely bigger than 65k.
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Re:Some ways DNS can break by matttpt on Monday January 17, 2022 @11:12AM (#29968036)
It sounds like you're thinking of zone transfers (the special AXFR query type). In that case the server's response may consist of more than one DNS message sent consecutively over a single TCP connection [1], so it's possible to transfer large zones. E.g. out of curiosity I just asked for the root zone with

  dig . axfr @iad.xfr.dns.icann.org
and I received 24,448 records transferred over 83 DNS messages, according to the stats dig prints at the end.

[1] https://datatracker.ietf.org/doc/html/rfc5936#section-2.2

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