Hi there,
My router have an ipv4 address. If my client (cellphone) get ipv4 address from the ISP the ovpn works well.
If my client get an ipv6 address (second SIM) then the tunnel can establish (I can see public ipv4 client address on the router), echo requests from the client reach the server but cannot reply to them (tcpdump tells "unreachable")
[root@xyz ~]# tcpdump -i eth0 icmp
tcpdump: verbose output suppressed, use -v or -vv for full protocol decode
listening on eth0, link-type EN10MB (Ethernet), capture size 262144 bytes
13:28:49.691972 IP 172.16.253.6 > xyz.abc.de: ICMP echo request, id 615, seq 1, length 64
13:28:49.692016 IP xyz.abc.de > 172.16.253.6: ICMP xyz.abc.de protocol 1 port 48194 unreachable, length 92
If the VPN tunnel established why can't traffic goes through?