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<p>Hi Zak,</p>
<p>PowerDNS Authoritative Server with mariadb/mysql backend is
vulnerable to ddos attacks:</p>
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<p><small class="site" style="font-weight:lighter;">github.com</small></p>
<p> <a href="#"
style="font-weight:600; text-decoration:none;"
moz-do-not-send="true"><big class="title">DDoS attack with
random A requests causes SQL backend overload · Issue
#11784 · PowerDNS/pdns</big></a> </p>
<p class="description">Hi, Program: Authoritative Issue type:
Feature request Short description DDoS attack with random A
requests causes SQL backend overload The zone cache feature
is only caching the "domains" table, it's not caching the
each record in the b...</p>
<p> <a href="https://github.com/PowerDNS/pdns/issues/11784"
class="url"
style="display:inline-block; text-decoration:none; text-indent:-2ch; margin-inline:2ch;"
title="github.com" moz-do-not-send="true">🔗
https://github.com/PowerDNS/pdns/issues/11784</a> </p>
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<p> Other back-ends may suffer from this issue, except LMDB.</p>
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<div class="moz-cite-prefix">On 10/31/25 4:57 PM, Zakaria via
Pdns-users wrote:<br>
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<blockquote type="cite"
cite="mid:e3f616f08374d6f3bbd60cdc963768d1@zakaria.website">
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Hi All,<br>
<br>
I have one question and wonder if anyone has answer for, and here
is the context first.<br>
<br>
I have been using PowerDNS, without database backend but just
plain bind db text files.<br>
<br>
I noticed my powerdns server setup is exceptionally fast when I
benchmark, in case for records anyone is interested, you can check
results out here:-<br>
<a class="moz-txt-link-freetext"
href="https://zakaria.website/dnsbenchmark.png"
moz-do-not-send="true">https://zakaria.website/dnsbenchmark.png</a><br>
<br>
I wondered if I switch to DB, would it hinder performance? This my
question, Does database like mysql and ldap get dns entries get
cached and in which format? is it like bind format in db text
files?<br>
<br>
Looking forward.<br>
<br>
With thanks.<br>
<br>
Zak. <br>
<br>
</blockquote>
<pre class="moz-signature" cols="72">--
Best regards,
Adrian Minta
</pre>
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