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<p class="MsoNormal"><span style="font-size:11.0pt">Suggest you test with 2.91 RC2.<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="font-size:11.0pt;font-family:"Calibri",sans-serif">From:</span></b><span style="font-size:11.0pt;font-family:"Calibri",sans-serif"> Dnsmasq-discuss <dnsmasq-discuss-bounces@lists.thekelleys.org.uk>
<b>On Behalf Of </b>Bryant Eadon<br>
<b>Sent:</b> Sunday, February 23, 2025 2:05 AM<br>
<b>To:</b> dnsmasq-discuss@lists.thekelleys.org.uk<br>
<b>Subject:</b> [Dnsmasq-discuss] Tracing a dnsmasq bug - hot loop - possibly DHCP6 lease management<o:p></o:p></span></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">Hello,<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">I am tracing an issue where <span class="gmail-il">dnsmasq</span> 2.86 appears to get stuck in a loop using all compute resources for the core it's on, and becomes unresponsive to DHCP4, DHCPv6 and DNS requests. I am working on replicating
the problem, and want to check to see if anyone on this list has seen the behavior before -- <o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">-- Details -- <o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">On the local LAN I am seeing 3 devices in DHCPv6 that are requesting IPV6 addresses every 10 minutes, even though their expiry time is advertised as 8 hours. I will have some difficulty finding the exact devices. It appears the DHCPv6
lease file continues tracking all of the leases on this openwrt based router.<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">A subset of these tracked requests are here, from the lease file -<o:p></o:p></p>
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<p class="MsoNormal">So, this is 48 entries (identical) in the dhcpv6 lease file per host that does this. There are 2 entries, per host (96 entries) .. and there are 3 hosts on the LAN doing this -- bringing the entries to 288 tracked leases, excluding the
IPV4 leases too.<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">My <span class="gmail-il">dnsmasq</span> config file is attached ( <span class="gmail-il">dnsmasq</span>-configfile.txt ). The only parameter I imagine is related :<o:p></o:p></p>
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<p class="MsoNormal"> dhcp-range=set:lan,192.168.2.40,192.168.2.254,255.255.255.0,8h<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">Notably - this is not a DHCPv6 setting, but it <b>does </b>show the 8h lease time I am seeing in the DHCPv6 leases , AND the parameters here have a limit of 215 addresses these hosts are pushing (the same) number of leases over 288 within
an 8hour span.<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">Has anyone seen this before ? Why are the IPv6 leases not replaced in the lease file when the same DUID requests addresses well before the end of the IPv6 lease time ?<o:p></o:p></p>
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<p class="MsoNormal">*Bonus* -- I've attached a pcap file for the DHCPv6 requests I think could be central to this problem. These packets arrived much later of course, well after I've experienced this problem, but may give us some insight to what's happening.<o:p></o:p></p>
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<p class="MsoNormal">Thank you,<o:p></o:p></p>
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<p class="MsoNormal">Bryant Eadon<o:p></o:p></p>
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<p class="MsoNormal"><img width="1" height="1" style="width:.0104in;height:.0104in" id="_x0000_i1025" src="https://mailfoogae.appspot.com/t?sender=aYnJ5YW50LmVhZG9uQGdtYWlsLmNvbQ%3D%3D&type=zerocontent&guid=614ec00b-1bf5-4313-91b7-90d89013ea0e"><span style="font-size:7.5pt;font-family:"Gadugi",sans-serif;color:white">ᐧ</span><o:p></o:p></p>
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