Using ocserv with systemd socket activation ------------------------------------------- ocserv can run in two modes: standalone or socket-activated. By default, ocserv in Debian is configured to be standalone mode, and listens on the standard https port 443. If you want to switch to systemd's socket activation feature, run: cp /usr/share/doc/ocserv/systemd/socket-activated/* /etc/systemd/system/ systemctl daemon-reload systemctl enable ocserv.socket To change the port that ocserv listens on when using ocserv.socket, create an override file /etc/systemd/system/ocserv.socket.d/*.conf with the following content: [Socket] ListenStream= ListenDatagram= ListenStream=12345 ListenDatagram=12345 For more details, see systemd.unit(5) and systemd.socket(5).