So I was trying out FreeBSD as a DSL router the last few days (+ DSL modem, only PPPoE on FreeBSD), with both ppp(8) and mpd5(8), which was successful. I also got DHCPv6 prefix delegation (IA_PD) working, which I advertised with rdadv to clients, but the FreeBSD router never got a v6 GUA on the WAN interface.After a couple hours of digging (as well as usage of tcpdump), I found out the ISP (Vodafone Business) only delegates a /56, but no /64 on the WAN, neither by SLAAC or DHCPv6 (IA_NA).Turnes out they expect you to allocate the first /64 of the /56 to the WAN interface yourself, which of course isn't documented anywhere online. This is easy enough if you have a static v6 prefic (which I do), but impractical with a dynamic v6 prefix.Really shows again and again that using IPv6 could be easy, but ISPs just have to be horrible, each in their own twisted way. 🤷♂️🤦♂️/rant over