Run x11vnc as a service for headless VNC

headless-xfce-vnc.sh

sudo tee /usr/local/bin/headless-xfce-vnc.sh >/dev/null <<'EOF'
#!/usr/bin/env bash
set -Eeuo pipefail

DISPLAY_NUM=${DISPLAY_NUM:-1}
GEOM=${GEOM:-1920x1080x24}
RFBPORT=${RFBPORT:-5900}
DISPLAY=":${DISPLAY_NUM}"
export DISPLAY

# 1) Start Xvfb
/usr/bin/Xvfb "$DISPLAY" -screen 0 "$GEOM" -nolisten tcp -noreset &
XVFB_PID=$!

# 2) Wait for the X socket to appear
for i in {1..60}; do
  [ -S "/tmp/.X11-unix/X${DISPLAY_NUM}" ] && break
  sleep 0.5
done

# 3) Start a desktop session under a D-Bus session
# (dbus-run-session cleans up on exit)
(/usr/bin/dbus-run-session /usr/bin/startxfce4) &

# 4) Serve it via VNC
exec /usr/bin/x11vnc -display "$DISPLAY" \
  -rfbauth "$HOME/.vnc/passwd" \
  -forever -shared -rfbport "$RFBPORT"
EOF
sudo chmod +x /usr/local/bin/headless-xfce-vnc.sh

install-service.txt

sudo systemctl daemon-reload
sudo systemctl enable  x11vnc-headless@<username>.service
sudo systemctl start   x11vnc-headless@<username>.service

prerequisites.txt

sudo apt update
sudo apt install x11vnc xvfb xfce4 xfce4-goodies dbus-x11
# make sure you have a VNC password file:
x11vnc -storepasswd

[email protected]

sudo tee /etc/systemd/system/[email protected] >/dev/null <<'EOF'
[Unit]
Description=Headless XFCE desktop over VNC for user %i
After=network-online.target
Wants=network-online.target

[Service]
Type=simple
User=%i
Environment=HOME=/home/%i
# Tweak these to taste:
Environment=DISPLAY_NUM=1
Environment=GEOM=1920x1080x24
Environment=RFBPORT=5900
ExecStart=/usr/local/bin/headless-xfce-vnc.sh
Restart=always
RestartSec=3

[Install]
WantedBy=multi-user.target
EOF