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<p class="MsoNormal"><span style="font-size:11.0pt">Bogdan,<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt">That had occurred to me as well. I have verified testing locally that when successful the value is printed in the log. I have also verified manually on the system with the error that the key does exist in
the cache, but the value in the cache is empty, just as in the log. That is what I believe is causing the failure, the lookup from the cache is successful (the key exists) but the value is empty, so OpenSIPS cannot route.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt">I have attempted increasing the logging on the system, but it appears the dns_cache module does not log anything further of use.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;color:black">Ben Newlin </span>
<span style="font-size:11.0pt"><o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"><o:p> </o:p></span></p>
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<p class="MsoNormal"><b><span style="color:black">From: </span></b><span style="color:black">Bogdan-Andrei Iancu <bogdan@opensips.org><br>
<b>Date: </b>Friday, December 7, 2018 at 12:21 PM<br>
<b>To: </b>OpenSIPS users mailling list <users@lists.opensips.org>, Ben Newlin <Ben.Newlin@genesys.com><br>
<b>Subject: </b>Re: [OpenSIPS-Users] DNS Cache module<o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:11.0pt"><o:p> </o:p></span></p>
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<p class="MsoNormal"><tt><span style="font-size:10.0pt">Hi Ben,</span></tt><span style="font-size:10.0pt;font-family:"Courier New""><br>
<br>
<tt>IMO, the log itself is broken as the data to be cached is not printable ....so the logs you see may be misleading.</tt><br>
<br>
<tt>When you say "OpenSIPS appeared to not be able to resolve the domain", you mean OpenSIPS is not doing any attempt to solve the FQDN, or you mean OpenSIPS is loading from cash something wrong ?</tt><br>
<br>
<tt>Regards,</tt><br>
<br>
</span><o:p></o:p></p>
<pre>Bogdan-Andrei Iancu<o:p></o:p></pre>
<pre><o:p> </o:p></pre>
<pre>OpenSIPS Founder and Developer<o:p></o:p></pre>
<pre> <a href="https://www.opensips-solutions.com">https://www.opensips-solutions.com</a><o:p></o:p></pre>
<pre>OpenSIPS Summit 2019<o:p></o:p></pre>
<pre> <a href="https://www.opensips.org/events/Summit-2019Amsterdam/">https://www.opensips.org/events/Summit-2019Amsterdam/</a><o:p></o:p></pre>
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<p class="MsoNormal">On 12/06/2018 10:17 PM, Ben Newlin wrote:<o:p></o:p></p>
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<p class="MsoNormal"><span style="font-size:11.0pt">Hello,</span><o:p></o:p></p>
<p class="MsoNormal"><span style="font-size:11.0pt"> </span><o:p></o:p></p>
<p class="MsoNormal"><span style="font-size:11.0pt">We use the DNS cache module to reduce the time spent querying DNS records. We recently had a customer call failing and we traced the failure to the customer using an FQDN in the Record-Route header. On the
ACK, OpenSIPS appeared to not be able to resolve the domain even though it had been successfully resolved on the initial request. I found the log for the DNS Cache module and noticed that the value it was inserting was empty:</span><o:p></o:p></p>
<p class="MsoNormal"><span style="font-size:11.0pt"> </span><o:p></o:p></p>
<p class="MsoNormal" style="line-height:11.25pt;background:white"><span style="font-size:8.5pt;font-family:"Courier New ;color:#333333",serif">INFO:<span style="background:#FAE9A4">dns_cache</span>:put_dnscache_value: putting key [dnscache_customer.domain.com_a]
with value [] ttl = 60</span><o:p></o:p></p>
<p class="MsoNormal"><span style="font-size:11.0pt"> </span><o:p></o:p></p>
<p class="MsoNormal"><span style="font-size:11.0pt">This prompted me to examine all of our logs and I found that the value for these DNS Cache logs is always empty, regardless of the domain. It appears the records are not being serialized properly into the
cache. </span><o:p></o:p></p>
<p class="MsoNormal"><span style="font-size:11.0pt"> </span><o:p></o:p></p>
<p class="MsoNormal"><span style="font-size:11.0pt">The DNS resolution must be succeeding or all of our requests using DNS would be failing, but I have also verified the domains all can be resolved manually on the same box:</span><o:p></o:p></p>
<p class="MsoNormal"><span style="font-size:11.0pt"> </span><o:p></o:p></p>
<p class="MsoNormal"><span style="font-size:8.5pt;font-family:"Courier New ;color:#333333",serif">$ nslookup customer.domain.com</span><o:p></o:p></p>
<p class="MsoNormal"><span style="font-size:8.5pt;font-family:"Courier New ;color:#333333",serif">Server: 10.27.0.2</span><o:p></o:p></p>
<p class="MsoNormal"><span style="font-size:8.5pt;font-family:"Courier New ;color:#333333",serif">Address: 10.27.0.2#53</span><o:p></o:p></p>
<p class="MsoNormal"><span style="font-size:8.5pt;font-family:"Courier New ;color:#333333",serif"> </span><o:p></o:p></p>
<p class="MsoNormal"><span style="font-size:8.5pt;font-family:"Courier New ;color:#333333",serif">Non-authoritative answer:</span><o:p></o:p></p>
<p class="MsoNormal"><span style="font-size:8.5pt;font-family:"Courier New ;color:#333333",serif">Name: customer.domain.com</span><o:p></o:p></p>
<p class="MsoNormal"><span style="font-size:8.5pt;font-family:"Courier New ;color:#333333",serif">Address: 10.27.172.132</span><o:p></o:p></p>
<p class="MsoNormal"><span style="font-size:8.5pt;font-family:"Courier New ;color:#333333",serif">Name: customer.domain.com</span><o:p></o:p></p>
<p class="MsoNormal"><span style="font-size:8.5pt;font-family:"Courier New ;color:#333333",serif">Address: 10.27.192.211</span><o:p></o:p></p>
<p class="MsoNormal"><span style="font-size:8.5pt;font-family:"Courier New ;color:#333333",serif">Name: customer.domain.com</span><o:p></o:p></p>
<p class="MsoNormal"><span style="font-size:8.5pt;font-family:"Courier New ;color:#333333",serif">Address: 10.27.255.53</span><o:p></o:p></p>
<p class="MsoNormal"><span style="font-size:11.0pt"> </span><o:p></o:p></p>
<p class="MsoNormal"><span style="font-size:11.0pt">Any thoughts? Is there more information I can obtain to determine the cause?</span><o:p></o:p></p>
<p class="MsoNormal"><span style="font-size:11.0pt"> </span><o:p></o:p></p>
<p class="MsoNormal"><span style="font-size:11.0pt;color:black">Ben Newlin </span>
<o:p></o:p></p>
<p class="MsoNormal"><span style="font-size:11.0pt"><br>
<br>
<br>
<o:p></o:p></span></p>
<pre>_______________________________________________<o:p></o:p></pre>
<pre>Users mailing list<o:p></o:p></pre>
<pre><a href="mailto:Users@lists.opensips.org">Users@lists.opensips.org</a><o:p></o:p></pre>
<pre><a href="http://lists.opensips.org/cgi-bin/mailman/listinfo/users">http://lists.opensips.org/cgi-bin/mailman/listinfo/users</a><o:p></o:p></pre>
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<br>
<o:p></o:p></span></p>
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