How to disconnect the VPN connection through terminal

Finally I managed to set up a vpn connection via sstp, with that command:

sudo /usr/local/sbin/sstpc --log-stderr --cert-warn --user <USERNAME> --password <PASSWORD> <SERVER> usepeerdns require-mschap-v2 noauth noipdefault defaultroute refuse-eap noccp

But now I don't know how to disable vpn. Help.

You've to find the sstpc running process and kill it.

There's a GUI for macOS:

https://www.axot.org/2015/03/03/isstp-a-sstp-client-for-mac-osx/ https://github.com/axot/isstp

Or you could setup a Launch Daemon and start and stop the daemon for it. https://www.launchd.info

It's really old VPN software that hasn't been updated in quite some time. Most people have moved on to other VPN solution such as OpenVPN, Wireguard, or other commercial solutions.

Good luck...