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--></style></head><body lang=DE link=blue vlink="#954F72" style='word-wrap:break-word'><div class=WordSection1><p class=MsoNormal>Hi all,</p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>I’m pretty sure I’m overlooking something really simple but somehow I’m stuck.</p><p class=MsoNormal><o:p> </o:p></p><div><p class=MsoNormal><span lang=EN-US>Initially I had a fairly standard setup: my router at home does IPv6 router advertisements + DHCP + DNS etc., local hosts do slaac and stateless dhcpv6.<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p></div><p class=MsoNormal><span lang=EN-US>Due to several reasons I wanted to move DHCP + DNS away from the router to a separate server. So what I did was<o:p></o:p></span></p><ul style='margin-top:0cm' type=disc><li class=MsoListParagraphCxSpFirst style='margin-left:0cm;mso-add-space:auto;mso-list:l0 level1 lfo1'><span lang=EN-US>Switch off DHCPv6 on the router<o:p></o:p></span></li><li class=MsoListParagraphCxSpMiddle style='margin-left:0cm;mso-add-space:auto;mso-list:l0 level1 lfo1'><span lang=EN-US>Keep Router Advertisements active on router (with O flag set)<o:p></o:p></span></li><li class=MsoListParagraphCxSpLast style='margin-left:0cm;mso-add-space:auto;mso-list:l0 level1 lfo1'><span lang=EN-US>Set up dnsmasq on the new dedicated DNS/DHCP server (Debian 11, dnsmasq 2.85). dnsmasq config is here: </span><a href="https://pastebin.aw.net/?f55651e94ecc6755#GhRFdiYGdzPpurJOks4etAmXx7u3dxGvuJQBdemNWOk="><span lang=EN-US>https://pastebin.aw.net/?f55651e94ecc6755#GhRFdiYGdzPpurJOks4etAmXx7u3dxGvuJQBdemNWOk=</span></a><span lang=EN-US><o:p></o:p></span></li></ul><p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US>What is now happening is that both the router as well as the dnsmasq server send router advertisements and my local hosts end up with two default routes. If I completely leave out the dhcp-range statement for IPv6, then dnsmasq will not send any router advertisements but unfortunately the really nice ra-names functionality is also switched off.<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US>Interestingly enough, my local Linux and MacOS don’t seem to be bothered at all by the two default routes while the Windows clients get confused sometimes (if I understand correctly depending on when they received which router advertisement).<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US>I tried to dig into the source code a bit and if I prevent dnsmasq from executing send_ra_aliases() that seems to do the trick. But I have to admit that I don’t understand the source code thoroughly enough and I assume this will break something else...<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US>So my question is: is there a way to stop dnsmasq from sending router advertisements while at the same still providing the ra-names functionality? <o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US>Thanks,<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US> Klaus<o:p></o:p></span></p><p class=MsoNormal><o:p> </o:p></p></div></body></html>