Add on-demand Xvfb + x11vnc socket activation
This commit is contained in:
Bumblebee
@@ -0,0 +1,233 @@
|
||||
# Xvfb + x11vnc On-Demand Setup
|
||||
|
||||
Run X11 server **only when needed** — zero overhead when idle.
|
||||
|
||||
## How It Works
|
||||
|
||||
```
|
||||
No one using X11
|
||||
↓
|
||||
Xvfb is STOPPED (no resources)
|
||||
|
||||
VNC client connects (or app needs X11)
|
||||
↓
|
||||
Systemd socket activation
|
||||
↓
|
||||
Xvfb starts automatically
|
||||
↓
|
||||
x11vnc connects to it
|
||||
↓
|
||||
You can use X11 apps or remote desktop
|
||||
|
||||
When done / no activity for N minutes
|
||||
↓
|
||||
Xvfb stops (auto)
|
||||
```
|
||||
|
||||
## Installation
|
||||
|
||||
### 1. Install Packages
|
||||
|
||||
```bash
|
||||
sudo apt-get update
|
||||
sudo apt-get install -y x11vnc xvfb
|
||||
```
|
||||
|
||||
### 2. Install Systemd Services
|
||||
|
||||
```bash
|
||||
sudo cp /workspace/second-brain/xvfb.socket /etc/systemd/system/
|
||||
sudo cp /workspace/second-brain/xvfb.service /etc/systemd/system/
|
||||
sudo cp /workspace/second-brain/x11vnc.service /etc/systemd/system/
|
||||
|
||||
sudo systemctl daemon-reload
|
||||
```
|
||||
|
||||
### 3. Enable Socket Activation (for Xvfb)
|
||||
|
||||
```bash
|
||||
sudo systemctl enable xvfb.socket
|
||||
sudo systemctl start xvfb.socket
|
||||
```
|
||||
|
||||
### 4. Enable VNC Service
|
||||
|
||||
```bash
|
||||
sudo systemctl enable x11vnc.service
|
||||
# Don't start yet — it will start when xvfb.socket gets activity
|
||||
```
|
||||
|
||||
### 5. Verify Setup
|
||||
|
||||
```bash
|
||||
# Socket should be listening
|
||||
sudo systemctl status xvfb.socket
|
||||
|
||||
# Services should be inactive initially
|
||||
sudo systemctl status xvfb.service
|
||||
sudo systemctl status x11vnc.service
|
||||
```
|
||||
|
||||
## Usage
|
||||
|
||||
### Start On-Demand
|
||||
|
||||
**Option A: VNC Connection Triggers It**
|
||||
```bash
|
||||
# From another machine, connect to VNC
|
||||
vnc-viewer 192.168.x.x:5900
|
||||
# → x11vnc and Xvfb start automatically
|
||||
```
|
||||
|
||||
**Option B: Manual Start**
|
||||
```bash
|
||||
# If you want to start without VNC connection
|
||||
sudo systemctl start xvfb.service
|
||||
sudo systemctl start x11vnc.service
|
||||
```
|
||||
|
||||
**Option C: Any App Needing X11**
|
||||
```bash
|
||||
# Any X11 app trying to connect to :99 will trigger it
|
||||
DISPLAY=:99 firefox &
|
||||
# → Xvfb starts automatically
|
||||
```
|
||||
|
||||
## Monitoring
|
||||
|
||||
### Watch Activation
|
||||
|
||||
```bash
|
||||
# See when services start/stop
|
||||
sudo journalctl -fu xvfb
|
||||
sudo journalctl -fu x11vnc
|
||||
```
|
||||
|
||||
### Check Current Status
|
||||
|
||||
```bash
|
||||
# Is Xvfb running?
|
||||
ps aux | grep Xvfb
|
||||
|
||||
# Is VNC listening?
|
||||
netstat -tlnp | grep 5900
|
||||
```
|
||||
|
||||
## Configuration
|
||||
|
||||
### Change VNC Port
|
||||
|
||||
Edit `/etc/systemd/system/x11vnc.service`:
|
||||
```
|
||||
ExecStart=/usr/bin/x11vnc -display :99 -forever -nopw -rfbport 5901
|
||||
```
|
||||
|
||||
Then reload:
|
||||
```bash
|
||||
sudo systemctl daemon-reload
|
||||
sudo systemctl restart x11vnc.service
|
||||
```
|
||||
|
||||
### Allow Remote Connections
|
||||
|
||||
Edit `/etc/systemd/system/x11vnc.service`:
|
||||
```
|
||||
# Change -localhost to -listen 0.0.0.0
|
||||
ExecStart=/usr/bin/x11vnc -display :99 -forever -nopw -listen 0.0.0.0
|
||||
```
|
||||
|
||||
### Add VNC Password
|
||||
|
||||
```bash
|
||||
# Generate password
|
||||
x11vnc -storepasswd
|
||||
|
||||
# Update service to use it
|
||||
ExecStart=/usr/bin/x11vnc -display :99 -forever -listen localhost -usepw
|
||||
```
|
||||
|
||||
### Adjust Display Resolution
|
||||
|
||||
Edit `/etc/systemd/system/xvfb.service`:
|
||||
```
|
||||
# Change 1920x1080x24 to your desired resolution
|
||||
ExecStart=/usr/bin/Xvfb :99 -screen 0 2560x1440x24
|
||||
```
|
||||
|
||||
## Auto-Stop (Inactivity)
|
||||
|
||||
To stop Xvfb after no activity (optional):
|
||||
|
||||
```bash
|
||||
# Install x-idle-logout if available
|
||||
# Or use a watchdog script
|
||||
|
||||
cat > /usr/local/bin/xvfb-watchdog.sh << 'EOF'
|
||||
#!/bin/bash
|
||||
# Stop Xvfb after 30 minutes of inactivity
|
||||
while true; do
|
||||
if ! pgrep -x Xvfb > /dev/null; then
|
||||
sleep 300
|
||||
continue
|
||||
fi
|
||||
|
||||
# Check if anyone is using the display
|
||||
xset -display :99 -q 2>/dev/null && IDLE=$(xset -display :99 q | grep "DPMS" | grep -oP '\d+m \d+s' | head -1)
|
||||
|
||||
if [ -z "$IDLE" ]; then
|
||||
# 30 minutes of inactivity
|
||||
sudo systemctl stop xvfb.service
|
||||
echo "Stopped Xvfb due to inactivity"
|
||||
sleep 600
|
||||
fi
|
||||
|
||||
sleep 60
|
||||
done
|
||||
EOF
|
||||
|
||||
chmod +x /usr/local/bin/xvfb-watchdog.sh
|
||||
|
||||
# Add to systemd (optional)
|
||||
sudo systemctl enable xvfb-watchdog.service
|
||||
```
|
||||
|
||||
## Troubleshooting
|
||||
|
||||
### Xvfb won't start
|
||||
|
||||
```bash
|
||||
sudo journalctl -u xvfb.service -n 20
|
||||
# Look for errors, usually permission or display binding issues
|
||||
```
|
||||
|
||||
### Can't connect to VNC
|
||||
|
||||
```bash
|
||||
# Check if x11vnc is running
|
||||
ps aux | grep x11vnc
|
||||
|
||||
# Check if port 5900 is listening
|
||||
sudo lsof -i :5900
|
||||
|
||||
# Check logs
|
||||
sudo journalctl -u x11vnc.service -n 20
|
||||
```
|
||||
|
||||
### Permissions error
|
||||
|
||||
```bash
|
||||
# Make sure x11vnc can access the display
|
||||
sudo chown -R intense:intense /tmp/.X11-unix/
|
||||
sudo chmod 1777 /tmp/.X11-unix/
|
||||
```
|
||||
|
||||
## Performance
|
||||
|
||||
- **Idle overhead:** <1MB RAM (Xvfb stopped)
|
||||
- **Running Xvfb:** ~100-200MB RAM
|
||||
- **With VNC client:** +50-100MB
|
||||
- **CPU:** Only when rendering, otherwise idle
|
||||
|
||||
---
|
||||
|
||||
Created: 2026-04-26
|
||||
@@ -0,0 +1,35 @@
|
||||
[Unit]
|
||||
Description=X11 VNC Server (On-Demand)
|
||||
After=network.target xvfb.service
|
||||
Requires=xvfb.service
|
||||
Documentation=http://www.karlrunge.com/x11vnc/
|
||||
|
||||
[Service]
|
||||
Type=simple
|
||||
User=intense
|
||||
Environment="DISPLAY=:99"
|
||||
|
||||
# Start x11vnc connected to Xvfb display :99
|
||||
# -forever: keep running
|
||||
# -nopw: no password required (can change)
|
||||
# -localhost: only local connections (can change to 0.0.0.0 for remote)
|
||||
ExecStart=/usr/bin/x11vnc -display :99 -forever -nopw -localhost -listen localhost
|
||||
|
||||
# Wait for display to be ready
|
||||
ExecStartPost=/bin/bash -c 'sleep 2 && echo "✓ VNC ready on :5900"'
|
||||
|
||||
# Restart on failure
|
||||
Restart=on-failure
|
||||
RestartSec=5
|
||||
|
||||
# Resource limits
|
||||
MemoryLimit=256M
|
||||
CPUQuota=30%
|
||||
|
||||
# Logging
|
||||
StandardOutput=journal
|
||||
StandardError=journal
|
||||
SyslogIdentifier=x11vnc
|
||||
|
||||
[Install]
|
||||
WantedBy=multi-user.target
|
||||
@@ -0,0 +1,29 @@
|
||||
[Unit]
|
||||
Description=X Virtual Framebuffer (On-Demand)
|
||||
After=network.target
|
||||
Documentation=https://www.x.org/wiki/
|
||||
|
||||
# Socket activation: starts only when x11vnc tries to connect
|
||||
Requires=xvfb.socket
|
||||
|
||||
[Service]
|
||||
Type=simple
|
||||
User=intense
|
||||
Environment="DISPLAY=:99"
|
||||
ExecStart=/usr/bin/Xvfb :99 -screen 0 1920x1080x24 -listen tcp
|
||||
|
||||
# Restart on failure
|
||||
Restart=on-failure
|
||||
RestartSec=5
|
||||
|
||||
# Resource limits
|
||||
MemoryLimit=512M
|
||||
CPUQuota=50%
|
||||
|
||||
# Logging
|
||||
StandardOutput=journal
|
||||
StandardError=journal
|
||||
SyslogIdentifier=xvfb
|
||||
|
||||
[Install]
|
||||
WantedBy=multi-user.target
|
||||
+13
@@ -0,0 +1,13 @@
|
||||
[Unit]
|
||||
Description=X Virtual Framebuffer Socket (Activation)
|
||||
Documentation=https://www.x.org/wiki/
|
||||
|
||||
[Socket]
|
||||
ListenStream=6000
|
||||
ListenUnix=/tmp/.X11-unix/X99
|
||||
|
||||
# Accept incoming connections and start xvfb.service
|
||||
Accept=no
|
||||
|
||||
[Install]
|
||||
WantedBy=sockets.target
|
||||
Reference in New Issue
Block a user