OpenVPN killswitch

[pearsimmon]

I can easily import an .ovpn file with the GUI network manager, but I'd also like to have a working killswitch, so that if VPN connection drops, I lose access to the Internet instead of reverting to my bare connection. I checked "advanced" options but I'm not that knowledgeable to understand everything. Is there an easy way to configure such killswitch for each VPN connection? Or even better, can such a killswitch be made so potent that there are no leaks even on OS boot?

[fehlix]

... can such a killswitch be made so potent that there are no leaks even on OS boot?

A nice explanation and howto for settings this up manually:
How to setup a manual kill switch to prevent OpenVPN leaks

[pearsimmon]

Well, I was hoping it is incorporated in network manager's GUI somewhere but if not, I will use iptables or ufw. The problem is that if I want to disable VPN sometimes to access my bank account for example, I will have to revert iptables or ufw manually.

[fehlix]

The problem is that if I want to disable VPN sometimes to access my bank account for example, I will have to revert iptables or ufw manually.

Either have one kill-switch script which toggles between two fire-wall rule states, or use two scripts to change between those rules.