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<p class="MsoNormal">For those of you facing a curious issue with BIND failing to resolve records for some zones today it’s not necessarily BIND having “a Friday moment”
<span style="font-family:"Segoe UI Emoji",sans-serif">😊</span><o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">It looks like the LetsEncrypt root certificate expiry is even impacting some DNSSEC zones that have used a LetsEncrypt certificate to sign their zone file.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">For example my BIND 9.17.18 / Ubuntu 21.04 servers are failing to resolve {anything}.slack.com at the moment, presumably because Slack have used LetsEncrypt to sign their zone. BIND is logging the following in my query-errors.log file:<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">(app.slack.com): query failed (broken trust chain) for app.slack.com/IN/A at query.c:7658<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">There’s a little more info about the LetsEncrypt issue at the following two links (not my site):<br>
<br>
<o:p></o:p></p>
<p class="MsoNormal"><a href="https://scotthelme.co.uk/lets-encrypt-old-root-expiration/">https://scotthelme.co.uk/lets-encrypt-old-root-expiration/</a><o:p></o:p></p>
<p class="MsoNormal">and<o:p></o:p></p>
<p class="MsoNormal"><a href="https://letsencrypt.org/docs/dst-root-ca-x3-expiration-september-2021/">https://letsencrypt.org/docs/dst-root-ca-x3-expiration-september-2021/</a><o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><span style="mso-fareast-language:EN-GB">Richard.<o:p></o:p></span></p>
<p class="MsoNormal"><o:p> </o:p></p>
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