OpenVPN client not connecting to OpenVPN Server with IPv6

[universe4]

Hello.

IPv4 connection works well for me, but I'd like to change to IPv6 and have been trying to so for a while, but no success.
So I want the public IP to be a IPv6 IP from the OpenVPN server.

If I try to connect with the changes done for IPv6, it won't work.

OpenVPN server version → OpenVPN 2.5.5 x86_64-pc-linux-gnu
The client on Windows is version 3.3.7 (2979).

The OpenVPN is running on an AWS Lightsail server, the IPv6 address/protocol has been enabled there.
Also, UDP 1194 has been added to the IPv6 firewall on AWS (the same as I had done for ipv4, which worked).

The client config:

View OriginalClient Config

client
#proto udp #default disabled
#remote 3.90.225.180 1194 #default disabled
proto udp6 #added myself
remote 26001b43926d:f1ad:b771:286d 1194 #added myself
explicit-exit-notify
dev tun
resolv-retry infinite
nobind
persist-key
persist-tun
remote-cert-tls server
verify-x509-name server_p3BWe6YJaLBrM6Ly name
auth SHA256
auth-nocache
cipher AES-256-GCM
tls-client
tls-version-min 1.2
tls-cipher TLS-ECDHE-ECDSA-WITH-AES-128-GCM-SHA256
ignore-unknown-option block-outside-dns
setenv opt block-outside-dns # Prevent Windows 10 DNS leak
verb 3
<ca>
...
...
...

The server config:

View OriginalServer Config

port 1194
#proto udp ## default
dev tun
user nobody
group nogroup
persist-key
persist-tun
keepalive 10 120
topology subnet
server 10.8.0.0 255.255.255.0
;ifconfig-pool-persist ipp.txt
push "dhcp-option DNS 1.0.0.1"
push "dhcp-option DNS 1.1.1.1"
push "redirect-gateway def1 bypass-dhcp"
dh none
ecdh-curve prime256v1
tls-crypt tls-crypt.key
crl-verify crl.pem
ca ca.crt
cert server_p3BWe6YJaLBrM6Ly.crt
key server_p3BWe6YJaLBrM6Ly.key
auth SHA256
cipher AES-256-GCM
ncp-ciphers AES-256-GCM
tls-server
tls-version-min 1.2
tls-cipher TLS-ECDHE-ECDSA-WITH-AES-128-GCM-SHA256
client-config-dir /etc/openvpn/ccd
status /var/log/openvpn/status.log
verb 3
duplicate-cn ##allow multiple connections
###############
###new ipv6 config below added myself
proto udp6
server-ipv6 26001b43:/64
tun-ipv6
push tun-ipv6
ifconfig-ipv6 26001b43:1 26001b43:2
push "route-ipv6 26001b43:/64"

What could be the reason, do I miss anything? Appreciate any help!

[universe4]

The problem was, OpenVPN Client was not up-to-date, and the previous version had a bug with IPv6 support.

I am able to connect on IPv6 now, however when browser on the internet, the IPv6 is NOT used:

This is what the client shows:

Code: Select all

Your IP: 2600:1f18:1b43:3500::1000

Server IP: 2600:1f18:1b43:3500:926d:f1ad:b771:286d

Port: 1194
Protocol: UDPv6

It seems that when browsing it is using the openvpn IPv4 and for IPv6 it says "Not detected".

What could be wrong?