Hi Bernd
please check my working config AXT1800 > Fritzbox 6591, I have the same demands as you. Please add in your config the Endpoint = xxxxxxxxxxxx@myfritz.net:xxxxxx
10.0.2.1 is the IP of the Fritzbox and 10.0.4.1 the GL.Inet AXT1800. If you have a diferent DNS Server as the FB, then you need to change that as well.
[Interface]
PrivateKey = xxxxxxxxxxxxxxxxxxxxxxxxxxxx
ListenPort = 51414
Address = 10.0.2.1/24
DNS = 10.0.2.1,10.0.4.1
[Peer]
PublicKey = xxxxxxxxxxxxxxxxxxxxxxxxx
PresharedKey = xxxxxxxxxxxxxxxxxxxxxxxxx
Endpoint = xxxxxxxxxxxxxxxx:xxxxxx
AllowedIPs = 10.0.4.0/24,0.0.0.0/0
PersistentKeepalive = 25