# x11vnc > A VNC server that will enable VNC on an existing display server. > By default, the server will automatically terminate once all clients disconnect from it. > More information: . - Launch a VNC server that allows multiple clients to connect: `x11vnc -shared` - Launch a VNC server in view-only mode, and which won't terminate once the last client disconnects: `x11vnc -forever -viewonly` - Launch a VNC server on a specific display and screen (both starting at index zero): `x11vnc -display :{{display}}.{{screen}}` - Launch a VNC server on the third display's default screen: `x11vnc -display :{{2}}` - Launch a VNC server on the first display's second screen: `x11vnc -display :{{0}}.{{1}}`