IONOS DDNS Auto-Updater & Creator

A Python-based system service that automatically updates DNS records on IONOS. Unlike standard DDNS scripts, this solution uses the IONOS REST API, allowing it to:

1. Update existing DNS records.
2. Create new DNS records automatically if they don't exist.
3. Check the current DNS value before updating to avoid API rate limits.

Features

• Smart Check: Compares public IP with current DNS resolution before sending API requests.
• Auto-Discovery: Automatically detects which DNS Zone a subdomain belongs to.
• System Service: Runs as a background systemd service with crash protection.
• Logging: Detailed logs in /var/log/ionos-ddns.log.

Prerequisites

• Python 3
• An IONOS account with access to the "Developer API".
• An API Key (Prefix + Secret) generated at developer.hosting.ionos.com.

Installation

1. Clone the repository to /opt

It is recommended to install this in a system directory.

sudo mkdir -p /opt/ionos-ddns
sudo git clone [https://github.com/TWOJA_NAZWA/ionos-ddns.git](https://github.com/TWOJA_NAZWA/ionos-ddns.git) /opt/ionos-ddns
cd /opt/ionos-ddns

### 2. Install dependencies
'''
sudo apt update
sudo apt install python3-pip
sudo pip3 install -r requirements.txt

### 3. Configuration
'''
sudo nano config.json
'''
Fill in your api_prefix and api_secret.

Domains List: Edit domains.txt and add domains one per line:
'''
sudo nano domains.txt
'''
Example:
'''
mydomain.com
vpn.mydomain.com
server.other-domain.net
'''

### 4. Install System Service
Copy the service file to systemd directory:
'''
sudo cp ionos-ddns.service /etc/systemd/system/
'''
Reload daemon, enable and start the service:
'''
sudo systemctl daemon-reload
sudo systemctl enable ionos-ddns.service
sudo systemctl start ionos-ddns.service
'''

### Monitoring
Check the service status:
'''
sudo systemctl status ionos-ddns.service
'''
View logs:
'''
tail -f /var/log/ionos-ddns.log
'''

### How it works
The script runs in an infinite loop (every 10 minutes).

Fetches your current Public IP.

Reads domains.txt.

For each domain:

Finds the correct Zone ID via API.

Checks if an A-Record exists.

If exists: Checks if IP matches. If not, performs PUT (Update).

If missing: Performs POST (Create).