I have an interesting problem with NATv6 on the OPNsense.
if I run e.g. OpenVPN on all interfaces and set it to port 1194 (so that OpenVPN runs in the dual stack) I use NAT to redirect e.g. incoming traffic from port 443 to the "VPN IP".
With IPv4 this works perfectly. But not with IPv6.
Also the redirection from the WAN IP to a loopback interface fails.
So e.g.:
192.0.2.12:443 DNAT-> 192.0.2.12:1194 works
[2001:DB8::12]:443 DNAT-> [2001:DB8::12]:1194 does not work
[2001:DB8::12]:443 DNAT-> [lo1]:1194 does not work either
What am i doing wrong?
Have you tried setting the filter rule association to "pass"?
I just set "Filter rule association" to "Pass" ans it still does not work.
Also worth mentioning is that a Filter rule on wan with "pass" for 443 TCP (VPN-IPv6) also exists.
Someone else also has a similar issue:
https://www.reddit.com/r/opnsense/comments/110n7cc/nat_redirect_for_dns_on_ipv6_loopback_address/
Also not working with the IPv6 itself. Like described in my first post.
Do you have outbound NAT for IPv6?
In normal cases i route ipv6.
But in this special case i enabled "NAT reflection" in the port forwarding rule.
It does not work either. Same issue with wireguard IPv6 NAT.