cat > /etc/systemd/system/x11vnc.service <<EOF 
[Unit]
Description=Service x11vnc
Requires=display-manager.service
After=display-manager.service

[Service]
Type=simple
ExecStart=/usr/bin/x11vnc -rfbauth /path/.vncpasswd -o /var/log/x11vnc.log -display :0 -auth /var/run/lightdm/root/:0 -forever -shared -rfbport 5900
Restart=on-failure
RestartSec=3

[Install]
WantedBy=multi-user.target
EOF