Sorry ill try to explain.
I have Synology directory server and DNS server (who comes along with directory server) installed on my Nas.
I want the domain users can login on my vpn server that's installed on my router.
Therefore the router must join the domain.
But when i do that and i reboot my router the computer and all other devices on the network have no internet connection any more.
But i found out i on the DNS sever i did not have changed the Forwarder on Resolution.
It was the ip adres of my router.