Link Monitor is a production-grade web application for real-time monitoring of network links and devices using ping-based checks. It provides a responsive dashboard with live updates, alerts, and historical data export capabilities.

• Real-time Monitoring: Continuously pings configured devices and displays status, latency, and packet loss in real-time.
• Web Dashboard: Responsive web interface with device cards showing current status, uptime percentage, average latency, and mini trend charts.
• Alerts System: Automatic alerts for high latency, packet loss, and connection issues with color-coded notifications.
• Device Management: Dynamically add or remove devices to monitor via the web interface. Device list is auto-persisted.
• Historical Data: Maintains a configurable history of ping results with trend calculations for uptime and average latency.
• Data Export: Export device history to JSON or CSV formats for analysis.
• REST API: Provides API endpoints for retrieving device lists and historical data.
• Logging: Saves error logs to disk in JSON Lines format per device.
• Configurable: Fully configurable via environment variables (port, ping interval, alert thresholds, etc.).
• Parallel Pinging: Uses parallel ping operations for faster checks on multiple devices.
• PWA Support: Installable as a Progressive Web App for offline access.
• Real-time Updates: Uses Socket.IO for instant updates across connected clients.
• Search Functionality: Search and filter devices in the dashboard.
• Client Tracking: Displays the number of connected clients.

1. Clone the repository:

   git clone <repository-url>
   cd app-link-monitor

2. Install dependencies:

   npm install

3. (Optional) Create a .env file in the root directory with configuration variables:

   PORT=3086
   PING_INTERVAL=1000
   HISTORY_LIMIT=50
   ALERT_LATENCY=200
   ALERT_LOSS=50
   LOG_LEVEL=info
   DEVICES_FILE=devices.json
   

npm run dev

npm start

The application will start on the configured port (default: 5000 or as set in .env).

1. Install PM2 globally:

   npm install -g pm2

2. Start the app with PM2:

   pm2 start server.js --name "link-monitor"

3. Save the process list:

   pm2 save

4. Enable auto-start on system boot:

   pm2 startup

• Check running apps: pm2 list
• Show logs in real-time: pm2 logs link-monitor
• Restart app: pm2 restart link-monitor
• Stop app: pm2 stop link-monitor
• Delete app: pm2 delete link-monitor

1. Open your browser and navigate to http://localhost:<PORT> (replace with your configured port).
2. The dashboard will display default devices (Cloudflare DNS and Google DNS).
3. Add new devices by entering a name and IP address in the "New Link" card.
4. Monitor real-time status, view trend charts, and receive alerts.
5. Export historical data using the export buttons on each device card.
6. Use the search bar to filter devices.

• GET /api/devices: Retrieve the list of monitored devices.
• GET /api/history/:name: Get historical ping data for a specific device.
• GET /api/export/json/:name: Export device history as JSON.
• GET /api/export/csv/:name: Export device history as CSV.

The application can be configured using environment variables:

• PORT: Server port (default: 5000)
• PING_INTERVAL: Ping check interval in milliseconds (default: 5000)
• HISTORY_LIMIT: Number of historical entries to keep (default: 100)
• ALERT_LATENCY: Latency threshold for alerts in ms (default: 200)
• ALERT_LOSS: Packet loss threshold for alerts in % (default: 50)
• LOG_LEVEL: Logging level (default: info)
• DEVICES_FILE: Path to devices JSON file (default: devices.json)

• Node.js
• Express.js
• Socket.IO
• Ping library
• Chart.js
• Bootstrap
• Pino (logging)

ISC