RFC 1207:FYI on Questions and Answers: Answers...
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RR


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... These problems have been related to TCP connections, NS RRs with small TTLs, and several other causes. Experience suggests that ...
... 1034std13 [2], section 4.2.1, one should not have to code glue RR's for name server's names ...
... unless they are below the cut. When I don't put glue RR's in, and do a query for NS ...



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