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<p style="margin-top:0;margin-bottom:0">RFC say all</p>
<p style="margin-top:0;margin-bottom:0">read RFC</p>
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<p style="margin-top:0;margin-bottom:0">BIND is a DNS system not an alien so follow RFC</p>
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<p style="margin-top:0;margin-bottom:0">Go and read RFC</p>
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<div id="divRplyFwdMsg" dir="ltr"><font style="font-size:11pt" face="Calibri, sans-serif" color="#000000"><b>From:</b> bind-users <bind-users-bounces@lists.isc.org> on behalf of ip admin via bind-users <bind-users@lists.isc.org><br>
<b>Sent:</b> Friday, October 5, 2018 4:13 PM<br>
<b>To:</b> bind-users@lists.isc.org<br>
<b>Subject:</b> Which timeouts are used by BIND when resolving recursive queries?</font>
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<div>Hi,</div>
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<div> I understand that I can configure a global timeout for resolving recursive queries (resolver-query-timeout) but find that I cannot configure the timeout for an individual query used during DNS resolution.</div>
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<div> For testing I configured one unreachable forwarder (and enabled forward only) and saw (tcpdump) that BIND (9.10.6-P1) is first trying two queries with EDNS which each seems to have a timeout of 1.2s. Afterwards queries without ENDS are sent which seem
to have a timeout of 1.6s, then 3.2s, then 6.4s, then 9s, finally the maximum (=total) resolver-query-timeout of 30s is reached.</div>
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<div> Is the timeout behaviour documented anywhere (similar to a stub resolver or dig, i.e. how long are timeouts, how many tries per server etc).</div>
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<div> If someone did find a logging setting that shows which servers are used when recursing (forwarding or delegations) to find a response (and when the individual queries time out) that would be helpful as well.<br>
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<div>Regards</div>
<div> Tom</div>
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