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<p class="MsoNormal">We have an environment that consists of two PDNS servers that are using a MySQL backend.</p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Server A holds a PDNS instance and the MySQL master.</p>
<p class="MsoNormal">Server B holds a PDNS instance and the MySQL slave.</p>
<p class="MsoNormal">Each server is configured to use its local MySQL instance for the backend.</p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">The primary use of these systems is to answer ENUM queries from our session border controllers for call routing decisions.</p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">First Oddity -</p>
<p class="MsoNormal">For each inbound call, the active SBC sends a query to both servers simultaneously. I can see the queries hitting port 53 via tcpdump, the odd thing is that only one server will send a reply i.e. if server A replies, server B does not and
vice versa. This is causing the SBC some concern and it is alarming that an ENUM server is out of service.</p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Second Oddity –</p>
<p class="MsoNormal">Whichever server replies, appears to be sending 3 responses. See below:</p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">22:40:00.778687 IP X.X.X.X.blackjack > BS-VM-M75-1.domain: 13136+ NAPTR? 0.0.0.2.7.7.5.1.0.3.e164.arpa. (47)<o:p></o:p></p>
<p class="MsoNormal">22:40:00.779173 IP BS-VM-M75-1.domain > X.X.X.X.blackjack: 13136* 1/0/0 (107)<o:p></o:p></p>
<p class="MsoNormal">22:40:00.779177 IP BS-VM-M75-1.domain > X.X.X.X.blackjack: 13136* 1/0/0 (107)<o:p></o:p></p>
<p class="MsoNormal">22:40:00.779178 IP BS-VM-M75-1.domain > X.X.X.X.blackjack: 13136* 1/0/0 (107)</p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Both of these behaviors seem a little odd to me, any thoughts?</p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Thanks,</p>
<p class="MsoNormal">Rob<o:p></o:p></p>
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