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<font color="#9FA2A5"><span style="padding-left:6px">Tuesday, December
30, 2014 9:17 AM</span></font></div></div></div>
<div style="color: rgb(136, 136, 136); margin-left: 24px;
margin-right: 24px;" __pbrmquotes="true" class="__pbConvBody"><pre wrap="">Colm MacCarthaigh wrote:
</pre><blockquote type="cite"><pre wrap="">Yes, that clearly violates the TTL of the rrset, but wouldn't be
over-all better for the health of the internet?
</pre></blockquote><pre wrap=""><!---->
Paul Vixie wrote:
</pre><blockquote type="cite"><pre wrap="">no. sometimes the old value is dangerous (private; load; loss) to the
person who changed it.
</pre></blockquote><pre wrap=""><!---->
On the other hand, since implementing it in our own local resolvers I
can tell you that the feature has absolutely averted customer
incidents, and never once caused one by using stale data.</pre></div>
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<br>
i think you mean "we have heard no reports of incidents caused by stale
data"?<br>
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<pre wrap="">
Thus personally I would say that the answer to Colm's question is a
qualified yes. I don't disagree with you about there being
problematic cases, but if we had let the perfect be the enemy of the
good we wouldn't even have the practical Internet and the World Wide
Web today. On balance to me the feature is "over-all better" for DNS
resilience.
I've been considering writing up an I-D and/or presenting to SSAC
about our experiences with it and recommendations for how to handle it
operationally. Should make for a lively discussion.
</pre>
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<br>
i think it's worth debating and/or standardizing, but ought not be done
without case by case permission otherwise. if the real problem is "ttl's
are too short" or "rdns servers should save and restore their cache
across restarts" then i'd rather we solve the real problem. violating
other people's reasonable assumptions meanwhile shouldn't be an option.<br>
<br>
see also: <a class="moz-txt-link-rfc2396E" href="http://queue.acm.org/detail.cfm?id=1242499"><http://queue.acm.org/detail.cfm?id=1242499></a>.<br>
<br>
<div class="moz-signature">-- <br>Paul Vixie<br>
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