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<div class="moz-cite-prefix">Hi Niall,<br>
<br>
Assumption:<br>
Possibly a wrong configured dnsdist [1] cache [2] in front of the
authoritative name server. If you miss the "dontAge" switch,
that's exactly the effect you'll have.<br>
<br>
Winfried<br>
<br>
[1] <a class="moz-txt-link-freetext" href="https://dnsdist.org/">https://dnsdist.org/</a><br>
[2]
<a class="moz-txt-link-freetext" href="https://dnsdist.org/reference/config.html?highlight=dontAge#newPacketCache">https://dnsdist.org/reference/config.html?highlight=dontAge#newPacketCache</a><br>
<br>
<br>
Am 07.01.2020 um 13:20 schrieb Niall O'Reilly:<br>
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cite="mid:7DE0EBE5-6092-4171-91EE-4CD14F88A209@ucd.ie">
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<p dir="auto">Hi.</p>
<p dir="auto">I've had my attention drawn to some surprising
behaviour by<br>
certain authoritative name servers. I'm not sure how best<br>
to categorize this behaviour, and wonder how some of you<br>
might view it.</p>
<p dir="auto">What's surprising is that an authoritative name
server<br>
shows both a decremented TTL value (as if it were answering<br>
from cache) and the AA flag.</p>
<p dir="auto">I'm not sure which of the following labels is
the best fit<br>
for this behaviour:</p>
<ul>
<li>normal and expected (but so far outside my experience),</li>
<li>strange but harmless,</li>
<li>downright wrong.</li>
</ul>
<p dir="auto">Thanks in advance to whomever is minded to
reply.</p>
<p dir="auto">Thanks especially to Mats Dufberg who,
diligently<br>
investigating what I had mistakenly guessed was a problem<br>
in zonemaster, took time to identify, and make me aware of,<br>
what was causing occasional trouble reports.</p>
<p dir="auto">Niall</p>
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