I'm currently using OpenBSD with an Andrews & Arnold vDSL connection so I have a pppoe(4) interface, etc. and this works for IPv4 & IPv6.
The problem is because of the rubbish rural Openreach infrastructure here in the UK I only get a stable 3.5 Mb/s, however another ISP (Voneus) has been installing fibre in the area and can offer a 100+ Mb/s connection, but it looks like their network is all sorts of CGNAT and they don't seem to offer IPv6 addresses. So I figured I'll just use the A&A L2TP relay service and use this new fast connection to tunnel all of my traffic between the two ISPs and maintain the IPv4 & IPv6 addesses that A&A have assigned to me on my vDSL connection. Has anyone done this with OpenBSD? I understand xl2tpd is in ports but does everything work through the tunnel, including IPv6? I saw mention about 8-9 years ago that the pppd(8) that xl2tpd uses doesn't do IPv6. Is that still the case? Thanks Matt
