# Mullvad VPN Server Pinger

A tool to identify the fastest Mullvad VPN servers, designed to work from behind the Great Firewall of China.

## Features
- Offline operation using locally cached server list
- Tests both IPv4 and IPv6 connectivity (when available)
- Generates CSV reports with latency metrics
- Works without API access

## Quick Start

1. **Generate server list**:
   ```bash
   mullvad relay list > relaylist.txt
   ```

2. **Run the pinger**:
   ```bash
   python ping_mullvad_relays.py
   ```

3. **Analyze results**:
   - Output saved to `mullvad_relays_ping.csv` by default
   - Sort by `rtt_ms` column to find fastest servers

## Advanced Usage

```bash
# Test only WireGuard servers with IPv6
python ping_mullvad_relays.py --protocols wireguard --ipv6

# Save to custom file with higher concurrency
python ping_mullvad_relays.py --output fast_servers.csv --concurrency 200

# Test specific ports (for TCP connectivity checks)
python ping_mullvad_relays.py --probe tcp --tcp-ports "443,51820"
```

## China-Specific Notes
- The script automatically uses `relaylist.txt` as its data source
- No external API calls are made
- For best results, update `relaylist.txt` periodically when outside China

## Output Format
The CSV contains:
- Server hostname and IP
- Protocol (WireGuard/OpenVPN)
- Location and provider info
- Ping success status and latency (RTT)

Connect to your chosen server through the Mullvad app or using WireGuard configs.