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<p class="MsoNormal"><span lang="EN-US" style="mso-fareast-language:EN-US">That makes sense. Thanks!<o:p></o:p></span></p>
<p class="MsoNormal"><span style="mso-fareast-language:EN-US"><o:p> </o:p></span></p>
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<p class="MsoNormal"><span lang="EN-US">Regards,<o:p></o:p></span></p>
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<p class="MsoNormal"><span lang="PL">Grzegorz</span><span style="mso-fareast-language:EN-US"><o:p></o:p></span></p>
<p class="MsoNormal"><span style="mso-fareast-language:EN-US"><o:p> </o:p></span></p>
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<p class="MsoNormal"><b><span style="font-size:12.0pt;color:black">From: </span></b><span style="font-size:12.0pt;color:black">Hugo Salgado <hsalgado@nic.cl><br>
<b>Date: </b>Thursday 2021-02-04 at 16:40<br>
<b>To: </b>"Ponikierski, Grzegorz" <gponikie@akamai.com><br>
<b>Cc: </b>Michael Rabinovich <michael.rabinovich@case.edu>, RIPE Atlas <ripe-atlas@ripe.net><br>
<b>Subject: </b>Re: [atlas] querying the config<o:p></o:p></span></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">Hi Grzegorz. As far as I know, the dst_addr have the destination IP<o:p></o:p></p>
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<p class="MsoNormal">address of the packet that the probe sent for a DNS measurement. So<o:p></o:p></p>
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<p class="MsoNormal">if used the "use_probe_resolver:true" setting, it should be the<o:p></o:p></p>
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<p class="MsoNormal">"frontend" resolver in your characterization. One of the resolvers<o:p></o:p></p>
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<p class="MsoNormal">configured in probe's /etc/resolv.conf.<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">Regards,<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">Hugo<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">On 10:51 03/02, Ponikierski, Grzegorz wrote:<o:p></o:p></p>
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<p class="MsoNormal">It's important to notice that whoami.ds.akahelp.net will give you backend IP of resolver (IP used to communicate with authoritative name server). If somebody needs frontend IP then this query won't help.<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">Hugo or Robert, can you tell which IP (frontend or backend) we will get from dst_addr field?<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">Regards,<o:p></o:p></p>
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<p class="MsoNormal">Grzegorz<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">From: Michael Rabinovich <<a href="mailto:michael.rabinovich@case.edu">michael.rabinovich@case.edu</a>><o:p></o:p></p>
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<p class="MsoNormal">Date: Thursday 2021-01-28 at 17:01<o:p></o:p></p>
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<p class="MsoNormal">To: Hugo Salgado <<a href="mailto:hsalgado@nic.cl">hsalgado@nic.cl</a>><o:p></o:p></p>
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<p class="MsoNormal">Cc: RIPE Atlas <<a href="mailto:ripe-atlas@ripe.net">ripe-atlas@ripe.net</a>><o:p></o:p></p>
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<p class="MsoNormal">Subject: Re: [atlas] querying the config<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">Hi Randy,<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">In addition, whether it's the configuration or the IP address used by the probe for a query as Hugo suggested, this would only give you the entry point into the resolution path (and sometimes will be a private IP address of a simple forwarder). But
you can query for TXT record for whoami.ds.akahelp.net, which will return you the IP address of the egress resolver.<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">Misha<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">On Jan 27, 2021, at 4:03 PM, Hugo Salgado <<a href="mailto:hsalgado@nic.cl">hsalgado@nic.cl</a><<a href="mailto:hsalgado@nic.cl%3e">mailto:hsalgado@nic.cl></a>> wrote:<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">Hi Randy. I don't know if you can check the config, but if you launch<o:p></o:p></p>
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<p class="MsoNormal">a DNS measurement taking care to define use_probe_resolver:true, then<o:p></o:p></p>
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<p class="MsoNormal">in the dst_addr field of the results you will have the IP that it used<o:p></o:p></p>
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<p class="MsoNormal">as the resolver.<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">Hugo<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">On 12:23 27/01, Randy Bush wrote:<o:p></o:p></p>
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<p class="MsoNormal">howdy<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">so i wanted info about a probe's config, specifically what dns<o:p></o:p></p>
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<p class="MsoNormal">resolver(s) it is using. i could not figure out how to do this.<o:p></o:p></p>
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<p class="MsoNormal">assuming it was a lack of clueons, i asked a friend with far deeper<o:p></o:p></p>
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<p class="MsoNormal">atlas fu. they said such queries are not available. really?<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">[ yes we have bright ideas on how to discover this indirectly by<o:p></o:p></p>
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<p class="MsoNormal"> mining past data ]<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">but really?<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">randy<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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