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<p class="MsoNormal"><span lang="EN-US">Hi guys,<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">Recently I started to move some servers behind dnsdist (due to an NX Domain attack), I knew from my old employer time, that dnsdist was capable of handling things like nx blocking etc using dynamic blocks<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">I’ve set up a dynamic block, that will block clients for 60 seconds, if they’re performing queries that result in a lot of nxdomain responses, and it works great.<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">However, I’d love to get more insight into what is being targeted when these blocks actually happen – dnsdist logs the offending IP to syslog when it gets blocked, so I know the client(s) doing the excessive amount of
lookups.<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">Is there any relatively simple way in dnsdist to get things like topQueries/topResponses being performed at the time of the block, and maybe even things like the output of “grepq” (But I think this is harder to get, since
you’d have to first get the topQueries and select what you want to query from the ring buffer).<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">I wonder if anyone already has done this before, or can give any pointers to how it could be implemented somewhat easily (I’m by no means a lua guy
</span><span lang="EN-US" style="font-family:"Apple Color Emoji"">😃</span><span lang="EN-US">)<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">I’m using dnsdist 1.6rc2, if that makes any difference.<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">Thanks in advance, and thanks for an awesome piece of software!<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">Best Regards,<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">Lucas Rolff<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
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