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    <p>If the V6 route is missing, UDP packets sent to v6 hosts would
      fail immediately. dnsmasq tries to use usually some resolver,
      which is responding. If v6 timeouts, they should not become such.
      It tries to send query every 20 seconds or 50 queries to all
      servers. But in general, it should work fine on UDP. TCP is more
      difficult, there are unfixed issues.<br>
    </p>
    <div class="moz-cite-prefix">On 2/16/23 08:42, Gomathi Shankar P S
      wrote:<br>
    </div>
    <blockquote type="cite"
cite="mid:CAG5xxdN5W+CMHuCCk-p1uJ80KV=uSUqmNz0ZO54gtJC_07Q5xA@mail.gmail.com">
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        <div class="gmail_default" style="font-family:arial,sans-serif">Hi
          Team,</div>
        <div class="gmail_default" style="font-family:arial,sans-serif">We
          are facing an issue when we have the following pre-conditions</div>
        <div class="gmail_default" style="font-family:arial,sans-serif">
          <ul>
            <li>dnsmasq version - 2.83, and is running in strict-order </li>
            <li>both v6 and v4 nameservers are in the resolv file</li>
            <li>when v6 route is fails </li>
          </ul>
        </div>
        <div class="gmail_default" style="font-family:arial,sans-serif">there
          is no fail-over fallback to v4 from v6 nameserver for
          resolution.</div>
        <div class="gmail_default" style="font-family:arial,sans-serif"><br>
        </div>
        <div class="gmail_default" style="font-family:arial,sans-serif">I
          understand that dnsmasq only reaches V6 nameservers (note - we
          have both v6 and v4 nameservers in resolv.dnsmasq) when we
          have V6 IP.</div>
      </div>
    </blockquote>
    <p>I haven't seen any code preferring just IPv6 nameservers when
      there is also IPv4. It should treat them equally and choose
      last_server to be used by any response arrived. If that is only
      IPv4 servers, it should choose them.</p>
    <p>If that does not happen, can you provide log with --log-queries
      or pcap with recorded responses? I think it should work.<br>
    </p>
    <blockquote type="cite"
cite="mid:CAG5xxdN5W+CMHuCCk-p1uJ80KV=uSUqmNz0ZO54gtJC_07Q5xA@mail.gmail.com">
      <div dir="ltr">
        <div class="gmail_default" style="font-family:arial,sans-serif"><br>
        </div>
        <div class="gmail_default" style="font-family:arial,sans-serif">When
          V6 route fails (but still we have V6 IP), we would like
          dnsmasq to reach V4 nameservers when V6 route is failed.
          Currently, it forwards the domains only to V6 nameservers as
          we have V6 IPs. </div>
        <div class="gmail_default" style="font-family:arial,sans-serif"><br>
        </div>
        <div class="gmail_default" style="font-family:arial,sans-serif">In
          the case of "no-strict-order", dnsmasq is reaching out to all
          nameservers. </div>
        <div class="gmail_default" style="font-family:arial,sans-serif">Is
          it possible to let dnsmasq to reach out V4 nameservers if the
          route fails (no response from V6 nameservers)? </div>
        <div class="gmail_default" style="font-family:arial,sans-serif"><br>
        </div>
        <div class="gmail_default" style="font-family:arial,sans-serif">Regards</div>
        <div class="gmail_default" style="font-family:arial,sans-serif">Gomathi
          Shankar P S</div>
      </div>
      <br>
      <fieldset class="moz-mime-attachment-header"></fieldset>
      <pre class="moz-quote-pre" wrap="">_______________________________________________
Dnsmasq-discuss mailing list
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</pre>
    </blockquote>
    <pre class="moz-signature" cols="72">-- 
Petr Menšík
Software Engineer, RHEL
Red Hat, <a class="moz-txt-link-freetext" href="https://www.redhat.com/">https://www.redhat.com/</a>
PGP: DFCF908DB7C87E8E529925BC4931CA5B6C9FC5CB</pre>
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