@mike123 Sorry but I don't buy this.. How was windows 11 getting IPv6 if you did not provide it through pfsense? And windows 11 isn't going to share its internet connection without you enabling that feature.
Did you enable the mobile hotspot feature? I would like to see these connections you were seeing on thee other servers to IPv6 addresses.
Sure if you enabled IPv6 on this machine, or it got internet via IPv6 and you enabled mobile hotspot then yeah it could hand out IPv6 address to other clients.
None of which would have anything to do with pfsense.
network to get IPV6 via DHCP relay.
No not how it would work there would not be a dhcpv6 relay involved.
This device that your saying is browsing the internet via IPv6.. Can we see a traceroute from this device to some IPv6 address out on the internet..
If your windows 11 box is sharing its internet connection, I would disable that. And I would prob also just disable IPv6 on it if you don't want it using it either.
Its pretty simple to just not provide IPv6 to devices behind pfsense if you don't want to.