README

DNS Monitoring Service with Cloudflare API and Telegram Notifications

This repository provides a DNS monitoring service that checks the health of multiple IP addresses and dynamically updates DNS records using the Cloudflare API. The service also sends notifications via Telegram whenever a DNS record is updated.

Features

Automatic DNS Failover: Monitors multiple IP addresses and updates DNS records if a primary IP becomes unavailable.
Configurable Health Checks: Customize the port, timeout, and interval for health checks.
Telegram Notifications: Receive real-time notifications via Telegram when DNS records are updated.
Multi-language Support: Supports English and Chinese languages for configuration.
Interactive Menu: Provides an interactive menu to manage configuration.

Prerequisites

A server running a supported Linux distribution (Ubuntu, Debian, CentOS, RHEL, Fedora).
Python 3 installed on the server.
jq, supervisor, and nginx installed on the server.
Cloudflare account with an API key and email.
Telegram bot token and chat ID.

Installation

Run the Installer Script

bash <(curl -L -s https://raw.githubusercontent.com/zytakeshi/CloudflareDnsFailoverForVpns/main/setup_dns_monitor.sh)

Follow the Prompts

The installer will prompt you to enter:

Cloudflare API key
Cloudflare email
Telegram Bot API token
Telegram Chat ID
Custom Telegram API URL
Health check port, timeout, and interval
Fail threshold

Managing Configuration

Use the interactive menu to:

List domains
Modify domain IP addresses
Delete domains
Add new domains
Configure the language

Using a Reverse Proxy for Telegram API (Chinese Servers)

If you are using a server in China and facing issues connecting to the Telegram API, you can set up an Nginx reverse proxy to route requests to Telegram.

Nginx Configuration Example

## Telegram API Reverse Proxy
server {
    listen 80;
    listen [::]:80;
    server_name telegram.example.com;

    # Enforce HTTPS
    return 301 https://$server_name$request_uri;
}

server {
    listen 443 ssl;
    listen [::]:443 ssl;

    server_name telegram.example.com;

    ## Update with your SSL certificate paths
    ssl_certificate /etc/nginx/cert/full_chain.pem;
    ssl_certificate_key /etc/nginx/cert/private.key;

    ## DNS resolver
    resolver 8.8.8.8;

    # Forward bot requests to Telegram API
    location ~* ^/bot {
        proxy_buffering off;
        proxy_pass https://api.telegram.org$request_uri;
        proxy_http_version 1.1;
    }

    # Optional: You can use this to check server status, or disable it with return 403;
    location / {
        try_files $uri $uri /index.html;
    }
}

Uninstallation

To stop and remove the DNS monitor service, follow these steps:

Stop the Service:
```
sudo supervisorctl stop dnsmonitor
```

Remove the Supervisor Configuration:

sudo rm /etc/supervisord.d/dnsmonitor.conf

Reload Supervisor:

sudo supervisorctl reread
sudo supervisorctl update

Remove the DNS Monitor Files:
```
rm -rf /path/to/dns-monitor
```

License

This project is licensed under the GNU 3.0 License.

Contributing

Contributions are welcome! Please open an issue or submit a pull request for any improvements or features you'd like to add.