<html><head></head><body><div>Hi,</div><div><br></div><div>Since we upgraded to pdns-recursor 4.6 we sometimes experience some weird behaviour with queries via pdns-recursor.</div><div><br></div><div>Sometimes, when a previously queried record expires through it's TTL, the recursor does not provide an answer anymore, until it's restarted.</div><div><br></div><div>Unfortunately I am not able to reproduce this. It happens occasionally.</div><div>When it happens, we see this: </div><div><br></div><div>Faulty server:</div><div><br></div><div style="box-sizing: border-box; font-family: "Cascadia Code", Consolas, ui-monospace, Menlo, Monaco, monospace; font-size: 14px; font-style: normal; font-variant-ligatures: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; orphans: 2; text-align: start; text-indent: 0px; text-transform: none; white-space: pre; widows: 2; word-spacing: 0px;"><pre><span class="cm-line">dig @ns1 riecis.nl A
</span><span class="cm-line">
</span><span class="cm-line">; <<>> DiG 9.11.36-RedHat-9.11.36-3.el8 <<>> @ns1 riecis.nl A
</span><span class="cm-line">; (1 server found)
</span><span class="cm-line">;; global options: +cmd
</span><span class="cm-line">;; Got answer:
</span><span class="cm-line">;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 27148
</span><span class="cm-line">;; flags: qr rd ra ad; QUERY: 1, ANSWER: 0, AUTHORITY: 1, ADDITIONAL: 1
</span><span class="cm-line">
</span><span class="cm-line">;; OPT PSEUDOSECTION:
</span><span class="cm-line">; EDNS: version: 0, flags:; udp: 512
</span><span class="cm-line">;; QUESTION SECTION:
</span><span class="cm-line">;riecis.nl. IN A
</span><span class="cm-line">
</span><span class="cm-line">;; AUTHORITY SECTION:
</span><span class="cm-line">riecis.nl. 2828 IN SOA ns1.minvenj.nl. hostmaster.solvinity.com. 2022010301 1800 300 604800 3600
</span><span class="cm-line">
</span><span class="cm-line">;; Query time: 2 msec
</span><span class="cm-line">;; SERVER: xxx.xxx.xxx.xxx#53(xxx.xxx.xxx.xxx)
</span><span class="cm-line">;; WHEN: Tue Sep 20 12:16:55 CEST 2022
</span><span class="cm-line">;; MSG SIZE rcvd: 110</span></pre></div><div><br></div><div><div style="width: 71ch;">other server:</div><div style="width: 71ch;"><br></div><div style="box-sizing: border-box; font-family: "Cascadia Code", Consolas, ui-monospace, Menlo, Monaco, monospace; font-size: 14px; font-style: normal; font-variant-ligatures: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; orphans: 2; text-align: start; text-indent: 0px; text-transform: none; white-space: pre; widows: 2; word-spacing: 0px;"><pre><span class="cm-line">dig @ns2 riecis.nl A
</span><span class="cm-line">
</span><span class="cm-line">; <<>> DiG 9.11.36-RedHat-9.11.36-3.el8 <<>> @ns2 riecis.nl A
</span><span class="cm-line">; (1 server found)
</span><span class="cm-line">;; global options: +cmd
</span><span class="cm-line">;; Got answer:
</span><span class="cm-line">;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 61517
</span><span class="cm-line">;; flags: qr rd ra ad; QUERY: 1, ANSWER: 1, AUTHORITY: 0, ADDITIONAL: 1
</span><span class="cm-line">
</span><span class="cm-line">;; OPT PSEUDOSECTION:
</span><span class="cm-line">; EDNS: version: 0, flags:; udp: 512
</span><span class="cm-line">;; QUESTION SECTION:
</span><span class="cm-line">;riecis.nl. IN A
</span><span class="cm-line">
</span><span class="cm-line">;; ANSWER SECTION:
</span><span class="cm-line">riecis.nl. 224 IN A 159.46.204.40
</span><span class="cm-line">
</span><span class="cm-line">;; Query time: 1 msec
</span><span class="cm-line">;; SERVER: xxx.xxx.xxx.xxx#53(xxx.xxx.xxx.xxx)
</span><span class="cm-line">;; WHEN: Tue Sep 20 12:17:03 CEST 2022
</span><span class="cm-line">;; MSG SIZE rcvd: 54</span></pre><pre><span class="cm-line"><br></span></pre><pre><span class="cm-line"><br></span></pre><pre><span class="cm-line"><div><span style="font-family: Cantarell; font-size: 14.666667px; white-space: normal;">We have a fairly simple configuration, just on what address and port to listen on, to use the same address for outgoing queries, en a short list of addresses that are allowed to query.</span></div><div><br></div><div>I have confirmed this problem upto and including version 4.6.3</div><div><br></div><div>Anyone an idea on how to approach this matter?</div><div><br></div><div>Regards</div><div><br></div><div><br></div></span></pre><pre><br></pre></div>
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