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</o:shapelayout></xml><![endif]--></head><body lang=EN-AU link="#467886" vlink="#96607D" style='word-wrap:break-word'><div class=WordSection1><div><div><p class=MsoNormal>We are dealing with a rather strange DNS issue and I am hoping somebody will be able to assist us with understanding.<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>Via DHCP we are allocated two DNS servers<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal style='margin-bottom:12.0pt'><b>resolvectl <br>Global<br> Protocols: -LLMNR -mDNS -DNSOverTLS DNSSEC=no/unsupported<br> resolv.conf mode: stub<br><br>Link 2 (eth0)<br> Current Scopes: DNS<br> Protocols: +DefaultRoute -LLMNR -mDNS -DNSOverTLS DNSSEC=no/unsupported<br>Current DNS Server: 10.1.1.1<br> DNS Servers: 10.1.1.1 10.1.1.2<br> DNS Domain: reddog.<span class=gmail-li>domain</span>.local<br><br>Link 3 (enP28932s1)<br> Current Scopes: none<br> Protocols: -DefaultRoute -LLMNR -mDNS -DNSOverTLS DNSSEC=no/unsupported</b><o:p></o:p></p></div><div><p class=MsoNormal>The reverse lookup completes successfully<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal><b>dig -x 10.1.1.1</b> and <b>dig -x 10.1.1.2</b> both correctly resolve to the DNS server's hostnames<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>However the forward lookup fails <o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal><b>dig dnsserver1.domain.local -> Fails</b><o:p></o:p></p></div><div><div><p class=MsoNormal><b>dig dnsserver2.domain.local -> Fails </b><o:p></o:p></p></div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>However with specifying the DNS server explicitly the requests complete successfully<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><div><p class=MsoNormal><b>dig @10.1.1.1 dnsserver1.domain.local -> Works</b><o:p></o:p></p></div><div><div><p class=MsoNormal><b>dig @10.1.1.1 dnsserver2.domain.local -> Works </b><o:p></o:p></p></div></div><div><p class=MsoNormal><b>dig @10.1.1.2 dnsserver1.domain.local -> Works</b><o:p></o:p></p></div><div><div><p class=MsoNormal><b>dig @10.1.1.2 dnsserver2.domain.local -> Works</b><o:p></o:p></p></div></div></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>I don't understand why it works when we set the DNS server and fails when using the default system DNS servers.<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>Kind regards<o:p></o:p></p></div><div><p class=MsoNormal>Alex<o:p></o:p></p></div></div></div></body></html>