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</o:shapelayout></xml><![endif]--></head><body lang=DE link="#0563C1" vlink="#954F72"><div class=WordSection1><p class=MsoNormal><span lang=EN-GB>Thanks for a great dnsmasq software.<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-GB><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-GB>I’m using dnsmasq 2.79 in combination with IPv6 prefix delegation. The prefixes are changing daily due to daily reconnect of upstream router. Dhcpcd is used to handle prefix delegation on external interface and apply new address to internal interface (dmz0). Dnsmasq picks up the prefix assigned to the internal interface by dhcpcd and server RA and DHCPv6 server.<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-GB><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-GB>dhcp-range=set:dmz6,::,constructor:dmz0,ra-stateless,ra-names<o:p></o:p></span></p><p class=MsoNormal>dhcp-host=id:00:02:00:00:ab:11:9b:74:21:c0:e9:5d:1c:18,set:dmzfix6,[::56],dmzhost<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal><span lang=EN-GB>Initially the host gets IPv6 address via DHCPv6 correctly, DNS resolution works as expected, everything seems to be ok. But after reconnect (and according prefix change) the client stays with the IPv6 address from old prefix and doesn’t update it. I’ve used tcpdump to monitor DHCP-related traffic and could not see DHCPv6 RECONFIGURE message sent by dnsmasq to clients on prefix change. I assume that this is the cause of the problem: DHCP clients are not aware of changed prefix and can’t act without corresponding notification from server.<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-GB>As dhcp client I use build-in DHCP client from system-networkd, just for info, maybe it matters…<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-GB><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-GB>If I’m wrong with my assumption I’d appreciate any explanation helping me to configure dnsmasq and DHCP client properly.<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-GB><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-GB>Best regards,<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-GB style='font-size:10.5pt;font-family:Consolas;mso-fareast-language:DE'>--<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:10.5pt;font-family:Consolas;mso-fareast-language:DE'>Andrey Vakhitov<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:10.5pt;font-family:Consolas;mso-fareast-language:DE'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:10.5pt;font-family:Consolas;mso-fareast-language:DE'>E-Mail: <a href="mailto:andrei@vakhitov.net"><span style='color:blue'>andrey@vakhitov.net</span></a> Stuttgart, Germany<o:p></o:p></span></p><p class=MsoNormal><o:p> </o:p></p></div></body></html>