Wireguard: IPv6 issues, IPv4 is working fine

[haiflo]

Good morning,

some days ago i switched from a openwrt device to a opnsense vm.

I am using that firewall as a dns, dhcp and wireguard server. It is integrated into my local subnet and is connected with the lan port to my fritzbox. So it has not the function as a firewall directly.

Unfortunately wireguard has some issues with ipv6 connections. IPv4 connections are working fine. They are nated from my fritzbox over port 1194 to my opnsense. But if i try to connect over ipv6 to my wireguard server there is no handshake possible. BUT: I can see traffic on the wireguard interface(received and sent) and i notice data incoming from my client devices with wireshark and tcpdump. Ping and HTTPS from that devices are working fine, so i dont think that is a generel problem with ipv6.

At the moment i have no clue why it is not working probably.

Maybe you have got an idea how to solve that problem.

Thank you so far for your support.

With the best regards

Flo