<div dir="ltr"><div>As I said earlier, I have a dnsmasq setup in a 150 clients environment. We are running debian package 2.70-1 built from git. </div><div><br></div><div>These few days, we frequently have name lookup failure. I have no conclusion by now, but I suspect cache code is involved.</div>
<div><br></div><div>A log segment</div><div><br></div><div><colleague A in my team visit this site in browser><br></div><div><div>May 8 18:51:30 dnsmasq[22631]: query[A] <a href="http://www.iciba.com">www.iciba.com</a> from 10.2.3.102</div>
<div>May 8 18:51:30 dnsmasq[22631]: forwarded <a href="http://www.iciba.com">www.iciba.com</a> to 114.114.114.114</div><div>May 8 18:51:30 dnsmasq[22631]: query[A] <a href="http://goto.www.iciba.com">goto.www.iciba.com</a> from 10.2.3.102</div>
<div>May 8 18:51:30 dnsmasq[22631]: forwarded <a href="http://goto.www.iciba.com">goto.www.iciba.com</a> to 114.114.114.114</div><div>May 8 18:51:30 dnsmasq[22631]: reply <a href="http://www.iciba.com">www.iciba.com</a> is 58.68.226.32</div>
<div>May 8 18:51:30 dnsmasq[22631]: reply <a href="http://goto.www.iciba.com">goto.www.iciba.com</a> is <CNAME></div><div>< browser failed to load the page, dns query failed ></div><div><br></div><div><colleague B in my team visit this site by click url provided by A> </div>
<div>May 8 18:52:23 dnsmasq[22631]: query[A] <a href="http://www.iciba.com">www.iciba.com</a> from 10.2.1.194</div><div>May 8 18:52:23 dnsmasq[22631]: forwarded <a href="http://www.iciba.com">www.iciba.com</a> to 114.114.114.114</div>
<div>May 8 18:52:23 dnsmasq[22631]: reply <a href="http://www.iciba.com">www.iciba.com</a> is 58.68.226.32</div><div><br></div><div><colleague A tried again></div><div>May 8 18:52:39 dnsmasq[22631]: query[A] <a href="http://www.iciba.com">www.iciba.com</a> from 10.2.3.102</div>
<div>May 8 18:52:39 dnsmasq[22631]: forwarded <a href="http://www.iciba.com">www.iciba.com</a> to 114.114.114.114</div><div>May 8 18:52:39 dnsmasq[22631]: reply <a href="http://www.iciba.com">www.iciba.com</a> is 58.68.226.32</div>
<div><this time page load successfully></div><div><br></div><div>May 8 18:53:03 dnsmasq[22631]: query[A] <a href="http://goto.www.iciba.com">goto.www.iciba.com</a> from 10.2.3.102</div><div>May 8 18:53:03 dnsmasq[22631]: forwarded <a href="http://goto.www.iciba.com">goto.www.iciba.com</a> to 114.114.114.114</div>
</div><div><div>May 8 18:53:03 dnsmasq[22631]: reply <a href="http://goto.www.iciba.com">goto.www.iciba.com</a> is <CNAME></div><div><br></div><div><the following is I test from the router itself, by running 'host' and 'dig'></div>
<div><br></div><div>May 8 19:59:00 dnsmasq[22631]: query[A] <a href="http://www.iciba.com">www.iciba.com</a> from 10.2.0.1</div><div>May 8 19:59:00 dnsmasq[22631]: forwarded <a href="http://www.iciba.com">www.iciba.com</a> to 114.114.114.114</div>
<div>May 8 19:59:00 dnsmasq[22631]: reply <a href="http://www.iciba.com">www.iciba.com</a> is 58.68.226.32</div><div>May 8 19:59:04 dnsmasq[22631]: query[A] <a href="http://www.iciba.com">www.iciba.com</a> from 10.2.0.1</div>
<div>May 8 19:59:04 dnsmasq[22631]: forwarded <a href="http://www.iciba.com">www.iciba.com</a> to 114.114.114.114</div><div>May 8 19:59:04 dnsmasq[22631]: reply <a href="http://www.iciba.com">www.iciba.com</a> is 58.68.226.32</div>
<div>May 8 19:59:06 dnsmasq[22631]: query[A] <a href="http://www.iciba.com">www.iciba.com</a> from 10.2.0.1</div><div>May 8 19:59:06 dnsmasq[22631]: cached <a href="http://www.iciba.com">www.iciba.com</a> is 58.68.226.32</div>
<div>May 8 19:59:08 dnsmasq[22631]: query[A] <a href="http://www.iciba.com">www.iciba.com</a> from 10.2.0.1</div><div>May 8 19:59:08 dnsmasq[22631]: cached <a href="http://www.iciba.com">www.iciba.com</a> is 58.68.226.32</div>
<div>May 8 19:59:12 dnsmasq[22631]: query[A] <a href="http://www.iciba.com">www.iciba.com</a> from 10.2.0.1</div><div>May 8 19:59:12 dnsmasq[22631]: cached <a href="http://www.iciba.com">www.iciba.com</a> is 58.68.226.32</div>
<div>May 8 19:59:13 dnsmasq[22631]: query[A] <a href="http://www.iciba.com">www.iciba.com</a> from 10.2.0.1</div><div>May 8 19:59:13 dnsmasq[22631]: cached <a href="http://www.iciba.com">www.iciba.com</a> is 58.68.226.32</div>
<div>May 8 19:59:15 dnsmasq[22631]: query[A] <a href="http://www.iciba.com">www.iciba.com</a> from 10.2.0.1</div><div>May 8 19:59:15 dnsmasq[22631]: cached <a href="http://www.iciba.com">www.iciba.com</a> is 58.68.226.32</div>
<div>May 8 20:00:22 dnsmasq[22631]: query[A] <a href="http://www.iciba.com">www.iciba.com</a> from 10.2.0.1</div><div>May 8 20:00:22 dnsmasq[22631]: forwarded <a href="http://www.iciba.com">www.iciba.com</a> to 114.114.114.114</div>
<div>May 8 20:00:22 dnsmasq[22631]: reply <a href="http://www.iciba.com">www.iciba.com</a> is 58.68.226.32</div></div><div><br></div><div><br></div><div>The last 8 'dig' return (look at the TTL)</div><div><br></div>
<div><div><div><a href="http://www.iciba.com">www.iciba.com</a>. 557 IN A 58.68.226.32</div></div><div><a href="http://www.iciba.com">www.iciba.com</a>. 552 IN A 58.68.226.32<br>
</div></div><div><a href="http://www.iciba.com">www.iciba.com</a>. 550 IN A 58.68.226.32<br></div><div><a href="http://www.iciba.com">www.iciba.com</a>. 548 IN A 58.68.226.32<br>
</div><div><a href="http://www.iciba.com">www.iciba.com</a>. 544 IN A 58.68.226.32<br></div><div><div><a href="http://www.iciba.com">www.iciba.com</a>. 543 IN A 58.68.226.32</div>
</div><div><a href="http://www.iciba.com">www.iciba.com</a>. 541 IN A 58.68.226.32<br></div><div><a href="http://www.iciba.com">www.iciba.com</a>. 475 IN A 58.68.226.32<br></div>
<div><br></div><div><br></div><div><br></div><div>The following is earlier log I lookup a name from the router when given a unresolvable name.</div><div><br></div><div><br></div><div><div>root@b10gw:~# host <a href="http://en.cppreference.com">en.cppreference.com</a></div>
<div>Host <a href="http://en.cppreference.com">en.cppreference.com</a> not found: 2(SERVFAIL)</div><div>root@b10gw:~# host <a href="http://en.cppreference.com">en.cppreference.com</a></div><div>Host <a href="http://en.cppreference.com">en.cppreference.com</a> not found: 2(SERVFAIL)</div>
<div>root@b10gw:~# host <a href="http://en.cppreference.com">en.cppreference.com</a> 8.8.8.8</div><div>Using domain server:</div><div>Name: 8.8.8.8</div><div>Address: 8.8.8.8#53</div><div>Aliases:</div><div><br></div><div>
<a href="http://en.cppreference.com">en.cppreference.com</a> has address 74.114.88.128</div><div>root@b10gw:~# host <a href="http://en.cppreference.com">en.cppreference.com</a></div><div>Host <a href="http://en.cppreference.com">en.cppreference.com</a> not found: 2(SERVFAIL)</div>
<div>root@b10gw:~# host <a href="http://en.cppreference.com">en.cppreference.com</a></div><div><a href="http://en.cppreference.com">en.cppreference.com</a> has address 74.114.88.128</div><div>root@b10gw:~# host <a href="http://en.cppreference.com">en.cppreference.com</a></div>
<div><a href="http://en.cppreference.com">en.cppreference.com</a> has address 74.114.88.128</div><div>root@b10gw:~# host <a href="http://en.cppreference.com">en.cppreference.com</a></div><div><a href="http://en.cppreference.com">en.cppreference.com</a> has address 74.114.88.128</div>
<div>root@b10gw:~# host <a href="http://en.cppreference.com">en.cppreference.com</a></div><div><a href="http://en.cppreference.com">en.cppreference.com</a> has address 74.114.88.128</div><div>root@b10gw:~# host <a href="http://en.cppreference.com">en.cppreference.com</a></div>
<div><a href="http://en.cppreference.com">en.cppreference.com</a> has address 74.114.88.128</div><div>root@b10gw:~# host <a href="http://en.cppreference.com">en.cppreference.com</a></div><div><a href="http://en.cppreference.com">en.cppreference.com</a> has address 74.114.88.128</div>
</div><div><br></div><div><br></div><div><br></div><div><div>May 8 17:49:15 dnsmasq[17390]: query[A] <a href="http://en.cppreference.com">en.cppreference.com</a> from 10.2.0.1</div><div>May 8 17:49:15 dnsmasq[17390]: forwarded <a href="http://en.cppreference.com">en.cppreference.com</a> to 114.114.114.114</div>
<div>May 8 17:49:15 dnsmasq[17390]: reply <a href="http://en.cppreference.com">en.cppreference.com</a> is 74.114.88.128</div><div>May 8 17:49:15 dnsmasq[17390]: query[A] <a href="http://en.cppreference.com">en.cppreference.com</a> from 10.2.0.1</div>
<div>May 8 17:49:15 dnsmasq[17390]: forwarded <a href="http://en.cppreference.com">en.cppreference.com</a> to 114.114.114.114</div><div>May 8 17:49:15 dnsmasq[17390]: reply <a href="http://en.cppreference.com">en.cppreference.com</a> is 74.114.88.128</div>
<div>May 8 17:49:17 dnsmasq[17390]: query[A] <a href="http://en.cppreference.com">en.cppreference.com</a> from 10.2.0.1</div><div>May 8 17:49:17 dnsmasq[17390]: forwarded <a href="http://en.cppreference.com">en.cppreference.com</a> to 114.114.114.114</div>
<div>May 8 17:49:17 dnsmasq[17390]: reply <a href="http://en.cppreference.com">en.cppreference.com</a> is 74.114.88.128</div><div>May 8 17:49:17 dnsmasq[17390]: query[A] <a href="http://en.cppreference.com">en.cppreference.com</a> from 10.2.0.1</div>
<div>May 8 17:49:17 dnsmasq[17390]: forwarded <a href="http://en.cppreference.com">en.cppreference.com</a> to 114.114.114.114</div><div>May 8 17:49:17 dnsmasq[17390]: reply <a href="http://en.cppreference.com">en.cppreference.com</a> is 74.114.88.128</div>
<div>May 8 17:49:24 dnsmasq[17390]: query[A] <a href="http://en.cppreference.com">en.cppreference.com</a> from 10.2.0.1</div><div>May 8 17:49:24 dnsmasq[17390]: forwarded <a href="http://en.cppreference.com">en.cppreference.com</a> to 114.114.114.114</div>
<div>May 8 17:49:24 dnsmasq[17390]: reply <a href="http://en.cppreference.com">en.cppreference.com</a> is 74.114.88.128</div><div>May 8 17:49:24 dnsmasq[17390]: query[A] <a href="http://en.cppreference.com">en.cppreference.com</a> from 10.2.0.1</div>
<div>May 8 17:49:24 dnsmasq[17390]: forwarded <a href="http://en.cppreference.com">en.cppreference.com</a> to 114.114.114.114</div><div>May 8 17:49:24 dnsmasq[17390]: reply <a href="http://en.cppreference.com">en.cppreference.com</a> is 74.114.88.128</div>
<div>May 8 17:49:26 dnsmasq[17390]: query[A] <a href="http://en.cppreference.com">en.cppreference.com</a> from 10.2.0.1</div><div>May 8 17:49:26 dnsmasq[17390]: forwarded <a href="http://en.cppreference.com">en.cppreference.com</a> to 114.114.114.114</div>
<div>May 8 17:49:26 dnsmasq[17390]: reply <a href="http://en.cppreference.com">en.cppreference.com</a> is 74.114.88.128</div><div>May 8 17:49:26 dnsmasq[17390]: query[AAAA] <a href="http://en.cppreference.com">en.cppreference.com</a> from 10.2.0.1</div>
<div>May 8 17:49:26 dnsmasq[17390]: forwarded <a href="http://en.cppreference.com">en.cppreference.com</a> to 114.114.114.114</div><div>May 8 17:49:26 dnsmasq[17390]: reply <a href="http://en.cppreference.com">en.cppreference.com</a> is NODATA-IPv6</div>
<div>May 8 17:49:26 dnsmasq[17390]: query[MX] <a href="http://en.cppreference.com">en.cppreference.com</a> from 10.2.0.1</div><div>May 8 17:49:26 dnsmasq[17390]: forwarded <a href="http://en.cppreference.com">en.cppreference.com</a> to 114.114.114.114</div>
<div>May 8 17:49:27 dnsmasq[17390]: query[A] <a href="http://en.cppreference.com">en.cppreference.com</a> from 10.2.0.1</div><div>May 8 17:49:27 dnsmasq[17390]: cached <a href="http://en.cppreference.com">en.cppreference.com</a> is 74.114.88.128</div>
<div>May 8 17:49:27 dnsmasq[17390]: query[AAAA] <a href="http://en.cppreference.com">en.cppreference.com</a> from 10.2.0.1</div><div>May 8 17:49:27 dnsmasq[17390]: cached <a href="http://en.cppreference.com">en.cppreference.com</a> is NODATA-IPv6</div>
<div>May 8 17:49:27 dnsmasq[17390]: query[MX] <a href="http://en.cppreference.com">en.cppreference.com</a> from 10.2.0.1</div><div>May 8 17:49:27 dnsmasq[17390]: forwarded <a href="http://en.cppreference.com">en.cppreference.com</a> to 114.114.114.114</div>
<div>May 8 17:49:32 dnsmasq[17390]: query[A] <a href="http://en.cppreference.com">en.cppreference.com</a> from 10.2.0.1</div><div>May 8 17:49:32 dnsmasq[17390]: forwarded <a href="http://en.cppreference.com">en.cppreference.com</a> to 114.114.114.114</div>
<div>May 8 17:49:32 dnsmasq[17390]: reply <a href="http://en.cppreference.com">en.cppreference.com</a> is 74.114.88.128</div><div>May 8 17:49:32 dnsmasq[17390]: query[AAAA] <a href="http://en.cppreference.com">en.cppreference.com</a> from 10.2.0.1</div>
<div>May 8 17:49:32 dnsmasq[17390]: forwarded <a href="http://en.cppreference.com">en.cppreference.com</a> to 114.114.114.114</div><div>May 8 17:49:32 dnsmasq[17390]: reply <a href="http://en.cppreference.com">en.cppreference.com</a> is NODATA-IPv6</div>
<div>May 8 17:49:32 dnsmasq[17390]: query[MX] <a href="http://en.cppreference.com">en.cppreference.com</a> from 10.2.0.1</div><div>May 8 17:49:32 dnsmasq[17390]: forwarded <a href="http://en.cppreference.com">en.cppreference.com</a> to 114.114.114.114</div>
<div>May 8 17:49:33 dnsmasq[17390]: query[A] <a href="http://en.cppreference.com">en.cppreference.com</a> from 10.2.0.1</div><div>May 8 17:49:33 dnsmasq[17390]: forwarded <a href="http://en.cppreference.com">en.cppreference.com</a> to 114.114.114.114</div>
<div>May 8 17:49:33 dnsmasq[17390]: reply <a href="http://en.cppreference.com">en.cppreference.com</a> is 74.114.88.128</div><div>May 8 17:49:33 dnsmasq[17390]: query[AAAA] <a href="http://en.cppreference.com">en.cppreference.com</a> from 10.2.0.1</div>
<div>May 8 17:49:33 dnsmasq[17390]: forwarded <a href="http://en.cppreference.com">en.cppreference.com</a> to 114.114.114.114</div><div>May 8 17:49:33 dnsmasq[17390]: reply <a href="http://en.cppreference.com">en.cppreference.com</a> is NODATA-IPv6</div>
<div>May 8 17:49:33 dnsmasq[17390]: query[MX] <a href="http://en.cppreference.com">en.cppreference.com</a> from 10.2.0.1</div><div>May 8 17:49:33 dnsmasq[17390]: forwarded <a href="http://en.cppreference.com">en.cppreference.com</a> to 114.114.114.114</div>
<div>May 8 17:49:33 dnsmasq[17390]: query[A] <a href="http://en.cppreference.com">en.cppreference.com</a> from 10.2.1.194</div><div>May 8 17:49:33 dnsmasq[17390]: cached <a href="http://en.cppreference.com">en.cppreference.com</a> is 74.114.88.128</div>
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