Assuming you are using systemd the correct way to control it is:
sudo systemctl stop openhab.service
sudo systemctl start openhab.service
sudo systemctl restart openhab.service
/etc/init.d and /etc/init/openhab.conf is not used by systemd as far as I know. The actual startup config is located in /etc/systemd/system/multi-user.target.wants/openhab.service