Bind response to query's very small edns udp payload size
jw354 at cornell.edu
Fri Apr 15 15:24:25 UTC 2016
>> What does bind try to do if the client specifies a udp size of less than 512?
> From RFC 6891:
> Values lower than 512 MUST be treated as equal to 512.
The behavior I saw was a shorter authority section and no additional section (or TO)
when I specified a UDP buffer of 200 as opposed to sending a non-EDNS request.
But I do see that an EDS request with UDP buffer size 512 gives me
exactly the same result as with buffer size 200. I speculate
bind will skip part of its usual authority section and provide no
TC bit as long as it can give the full answer section.
The actual issue I was investigating is indeed unrelated. I was merely
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