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<p>Hello,</p>
<p><br>
</p>
<p>I recently stumbled upon a problem trying to update my root hints
file from <b><a class="moz-txt-link-abbreviated" href="ftp://ftp.rs.internic.net">ftp.rs.internic.net</a></b>. For some reason, one of my
DNS servers running on Alpine Linux, can't resolve this name
properly and always fails:</p>
<pre># ping <a class="moz-txt-link-abbreviated" href="ftp://ftp.rs.internic.net">ftp.rs.internic.net</a>
ping: <a class="moz-txt-link-abbreviated" href="ftp://ftp.rs.internic.net">ftp.rs.internic.net</a>: Try again
</pre>
nslookup starts off fine, it prints the A record, but then it fails
to:<br>
<pre>
# nslookup <a class="moz-txt-link-abbreviated" href="ftp://ftp.rs.internic.net">ftp.rs.internic.net</a>
Server: 127.0.0.1
Address: 127.0.0.1#53
Non-authoritative answer:
<a class="moz-txt-link-abbreviated" href="ftp://ftp.rs.internic.net">ftp.rs.internic.net</a> canonical name = <a class="moz-txt-link-abbreviated" href="ftp://ftp.rs.verisigndns.com">ftp.rs.verisigndns.com</a>.
Name: <a class="moz-txt-link-abbreviated" href="ftp://ftp.rs.verisigndns.com">ftp.rs.verisigndns.com</a>
Address: 69.58.179.79
** server can't find <a class="moz-txt-link-abbreviated" href="ftp://ftp.rs.verisigndns.com">ftp.rs.verisigndns.com</a>: SERVFAIL
</pre>
<p><br>
</p>
<p>It seems the problem is with AAAA records, as apparently musl
libc tries to resolve both A and AAAA record and fails if either
of them are not available. Unfortunately, I couldn't find a way to
configure the musl resolver not to try AAAA records.</p>
<p>Digging a bit deeper I found out that these queries cause BIND to
log errors:</p>
<pre>named[12737]: DNS format error from 185.100.2.22#53 resolving <a class="moz-txt-link-abbreviated" href="ftp://ftp.rs.verisigndns.com/AAAA">ftp.rs.verisigndns.com/AAAA</a> for 127.0.0.1#39521: Name rs.verisigndns.com (SOA) not subdomain of zone <a class="moz-txt-link-abbreviated" href="ftp://ftp.rs.verisigndns.com">ftp.rs.verisigndns.com</a> -- invalid response
named[12737]: DNS format error from 72.13.39.22#53 resolving <a class="moz-txt-link-abbreviated" href="ftp://ftp.rs.verisigndns.com/AAAA">ftp.rs.verisigndns.com/AAAA</a> for 127.0.0.1#39521: Name rs.verisigndns.com (SOA) not subdomain of zone <a class="moz-txt-link-abbreviated" href="ftp://ftp.rs.verisigndns.com">ftp.rs.verisigndns.com</a> -- invalid response
named[12737]: DNS format error from 69.36.158.22#53 resolving <a class="moz-txt-link-abbreviated" href="ftp://ftp.rs.verisigndns.com/AAAA">ftp.rs.verisigndns.com/AAAA</a> for 127.0.0.1#39521: Name rs.verisigndns.com (SOA) not subdomain of zone <a class="moz-txt-link-abbreviated" href="ftp://ftp.rs.verisigndns.com">ftp.rs.verisigndns.com</a> -- invalid response
named[12737]: DNS format error from 199.16.87.22#53 resolving <a class="moz-txt-link-abbreviated" href="ftp://ftp.rs.verisigndns.com/AAAA">ftp.rs.verisigndns.com/AAAA</a> for 127.0.0.1#39521: Name rs.verisigndns.com (SOA) not subdomain of zone <a class="moz-txt-link-abbreviated" href="ftp://ftp.rs.verisigndns.com">ftp.rs.verisigndns.com</a> -- invalid response
</pre>
<p><br>
</p>
<p>However, if I point the system resolver (or nslookup) to some
other DNS (my ISP's DNS, for examle), neither ping or nslookup
fail.<br>
</p>
<p><br>
</p>
<p>Is there anything I can do on my BIND to make musl libc happy and
not fail in such a case? <br>
</p>
<p><br>
</p>
<p> Thanks,</p>
<p> Danilo</p>
<p><br>
</p>
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