NetMonitor

Self-hosted network diagnostics toolkit with a modern dark UI. Deploy on any Node.js server.

Features

• IP Lookup — Public IPv4/IPv6 detection, geolocation with country flag, ISP/ASN info, proxy/VPN/Tor identification
• TLS/SSL Check — Certificate analysis, protocol version, cipher suites, security grading (A+ to F)
• HTTP Security Headers — HSTS, CSP, X-Frame-Options audit with scoring and hardening recommendations
• ECH Detection — Encrypted Client Hello support analysis with client-side browser detection and server-side deep probing
• Speed Test — Download/upload throughput measurement, latency, and jitter analysis
• DNS Leak Test — DNS resolver detection, leak risk assessment, provider identification
• Ping / Traceroute — Network path diagnostics with hop-by-hop latency breakdown
• History — Auto-saved detection records stored in browser localStorage
• Bilingual — Chinese/English interface with one-click switching
• Dark/Light Theme — System-aware theme toggle with manual override
• Legal Compliance — Multi-jurisdiction legal notices (PRC, EU, US, HK, Taiwan) with first-visit modal
• Click to Copy — All detection results are copyable with one click

Tech Stack

• Backend: Hono + TypeScript
• Frontend: React 19 + Vite + Tailwind CSS
• Runtime: Node.js 20+ LTS

Quick Start

# Install dependencies
npm install

# Development (server + client with hot reload)
npm run dev

# Production build
npm run build
npm start

Configuration

Copy .env.example to .env:

Variable	Default	Description
PORT	3000	Server port
HOST	0.0.0.0	Bind address
NODE_ENV	development	development or production
RATE_LIMIT_PER_MINUTE	30	Global rate limit per IP
MAX_SPEEDTEST_SIZE_MB	25	Max speed test payload
DNS_SERVERS	(system)	Custom DNS servers (comma-separated, e.g. 8.8.8.8,1.1.1.1)
LOG_LEVEL	info	Log level (debug/info/warn/error)
CORS_ORIGIN	*	CORS allowed origins
IPINFO_TOKEN	(empty)	ipinfo.io API token (optional)

API Endpoints

Method	Path	Description
GET	/api/health	Health check
GET	/api/ip/lookup?target=	IP/geolocation lookup
GET	/api/tls/check?host=	TLS certificate analysis
GET	/api/headers/check?url=	HTTP security headers audit
GET	/api/ech/check?host=	ECH basic check
GET	/api/ech/probe?host=	ECH deep probe (SNI analysis)
GET	/api/ech/client-probe	Client TLS metadata
GET	/api/speedtest/latency	Measure latency and jitter
GET	/api/speedtest/download?sizeMB=	Download speed test payload
POST	/api/speedtest/upload	Upload speed test
GET	/api/dns/leak-test	DNS leak detection
GET	/api/ping/ping?host=&count=	ICMP ping
GET	/api/ping/traceroute?host=&maxHops=	Traceroute

Deployment

PM2 + Nginx

# Build
npm install
npm run build
npm ci --production

# Start with PM2
pm2 start ecosystem.config.cjs
pm2 save
pm2 startup

Nginx config

server {
    listen 80;
    server_name your-domain.com;

    location / {
        proxy_pass http://127.0.0.1:3000;
        proxy_http_version 1.1;
        proxy_set_header Host $host;
        proxy_set_header X-Real-IP $remote_addr;
        proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
        proxy_set_header X-Forwarded-Proto $scheme;
        client_max_body_size 30m;
    }
}

HTTPS with Let's Encrypt

sudo certbot --nginx -d your-domain.com --non-interactive --agree-tos

One-click deploy (Ubuntu/Debian)

sudo ./deploy.sh --domain your-domain.com --email you@email.com

Project Structure

src/
├── server/                  # Backend API
│   ├── routes/              # API route handlers
│   ├── services/            # Core detection logic
│   ├── middleware/           # Rate limiting, error handling
│   ├── utils/               # DNS resolver, logger
│   └── index.ts             # Entry point
├── client/                  # Frontend SPA
│   └── src/
│       ├── components/      # Reusable UI components
│       ├── pages/           # Feature pages
│       ├── hooks/           # React hooks (locale, theme, API)
│       ├── lib/             # API client, history, ECH detection
│       └── legal/           # Legal documents & changelog
└── shared/                  # Shared TypeScript types

License

MIT

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