On 16Feb23, Dick Franks allegedly wrote: > The last statement is informatively and normatively mistaken. > The counterexample is to be found in RFC8490(5.4): > > A DSO message begins with the standard twelve-byte DNS message header > [RFC1035] with the OPCODE field set to the DSO OPCODE (6). However, > unlike standard DNS messages, the question section, answer section, > authority records section, and additional records sections are not > present. The corresponding count fields (QDCOUNT, ANCOUNT, NSCOUNT, > ARCOUNT) MUST be set to zero on transmission.
If we're looking for more counterexamples, there's also RFC7873#5.4 For servers with DNS Cookies enabled, the QUERY opcode behavior is extended to support queries with an empty Question Section (a QDCOUNT of zero (0)), provided that an OPT record is present with a COOKIE option. Such servers will send a reply that has an empty Answer Section and has a COOKIE option containing the Client Cookie and a valid Server Cookie. Mark. _______________________________________________ DNSOP mailing list DNSOP@ietf.org https://www.ietf.org/mailman/listinfo/dnsop
