I have had a look here and found several posts around this but none that was spot on, hopefully you can shed light over my issue

When a open vpn client user (siting on Ubuntu if that matters

All the traffic is being routed through the VPN and that is working as it should (with push gateway settings on server), but i would need the local lan access to be blocked when on openvpn.
So for example, a user at home connected through openvpn also accessing hes private nas at home should not be allowed.
Is there anyway of doing this with openvpn server config? Or do one need to look at perhaps setting up network manager dispatcher scripts that invoked iptables or similar on the client?
Any ideas on best and easiest way to do this and best practise?
B
