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<p>Anyone have a good contact for T-Mobile authoritative DNS? I've
had no response from <a class="moz-txt-link-abbreviated" href="mailto:dnsadmin@t-mobile.com">dnsadmin@t-mobile.com</a>.<br>
</p>
<p>My customers are reporting that T-Mobile WiFi calling
(sometimes) does not work on our Internet service. This appears
to be due to DNS resolution failures.</p>
<p>The cause of the failures seems to be that geo9.t-mobile.com
and geo10.t-mobile.com incorrectly return NXDOMAIN when queried
for NS records for
epdg.epc.geo.mnc260.mcc310.pub.3gppnetwork.org and
epc.geo.mnc260.mcc310.pub.3gppnetwork.org. Note that they
correctly return an answer when queried for A records. See also:
<a class="moz-txt-link-freetext"
href="https://dnsviz.net/d/epdg.epc.mnc260.mcc310.pub.3gppnetwork.org/dnssec/">https://dnsviz.net/d/epdg.epc.mnc260.mcc310.pub.3gppnetwork.org/dnssec/</a></p>
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<pre class="moz-signature" cols="72">--
Richard
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