Ipv6 needs ad least some icmpv6 rules to work. https://www.rfc-editor.org/rfc/rfc4890 If i didn't miss any adding the following icmp6 rules should make it work. # Destination unreachable (type 1) # Packet too big (type 2) # Time exceeded (type 3) # Parameter problem (type 4) # Echo Request (protect ...