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<p class="MsoNormal">Hello, <o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">We recently switched to using Unbound instead of DNSMasq to forward DNS requests to upstream servers. As a result we were informed that the change ‘broke” AWS EMR deployments. Since AWS VPC can be large and instances come and go quickly
the previous deployments leveraged doing forward and reverse DNS with a synthetic domain option:<o:p></o:p></p>
<p class="MsoNormal"><a href="https://serverfault.com/questions/862279/dnsmasq-as-authoritative-dns-server-with-synth-domain">https://serverfault.com/questions/862279/dnsmasq-as-authoritative-dns-server-with-synth-domain</a><o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">dnsmasq --listen-address=127.0.0.1 --synth-domain=vpc.internal,10.140.0.0/21,ip-<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">A lookup for an IP in the CIDR block 10.140.0.0/21 will return a name that it constructs with the parameters provided (for reverse DNS), it will also work for forward look ups.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">My question is if there is a similar option for Unbound? I cannot find anything in the documentation besides creating a local zone file with all the possible Ips/Names configured.
<br>
<br>
Thanks!<o:p></o:p></p>
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<p class="MsoNormal">-- <o:p></o:p></p>
<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Arial",sans-serif;color:black">Daniel</span><span style="font-size:12.0pt;color:black"><o:p></o:p></span></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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