Marco Moock <[email protected]> writes: > On 24.02.2026 12:00 Uhr Anssi Saari wrote: > >> The only successful name+address allocations from dnsmasq >> I've managed with IPv6 have been the EUI-64 kind. > > Those are not done by DHCPv6, but SLAAC. > Use a sniffer and check the DHCPv6 traffic to see if devices actually > use it. Do you have the M flag set in the RA?
Thanks, I took some time to poke at this. I ended up with this config in dnsmasq.conf: dhcp-range=::1000, ::2000, constructor:br0, ra-names, slaac, 20m It's effectively the same as what Harri posted up-thread. This creates addresses for DHCPv6 based on the fc00::/7 address on br0 interface and the range provided and serves both them and SLAAC addresses (which are the EUI-64 kind). 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.
