On 04.03.2026 14:20 Uhr Anssi Saari wrote: > What was curious is that this seemed to work on Windows clients but on > Linux with only one computer which runs NetworkManager. It's also my > only Debian 13 system. But no go on Linux boxes with systemd-networkd > but those are also older, Debian 12 and one Ubuntu 20.04. And no on > Android but I believe it still won't do DHCPv6 so it's expected. > > Turns out I apparently need to allow DHCPv6 explicitly in the firewall > at least on Debian 12? The stateful stuff in nftables doesn't seem to > cover DHCPv6 and in fact, I've done the same earlier on my router to > my ISP and the router is also running Debian 12.
Enable firewall logging and look for rejections. Also use Wireshark and check if the router advertisement includes the M flag (otherwise clients will not try to contact it) -- kind regards Marco Send spam to [email protected]

