Cloudflare DDNS

This repository provides a lightweight Dynamic DNS (DDNS) client for Cloudflare using a shell script and systemd timer. It checks your public IP periodically and updates your Cloudflare DNS A record if your IP changes.

Features

• Automatically detects your public IP
• Updates your DNS A record via Cloudflare API
• Skips update if IP hasn't changed
• Logs activity via systemd journal (journalctl -t cf-ddns)
• Fully automated installation with a single script

Prerequisites

• A domain managed in Cloudflare
• Zone ID of the domain
• A DNS record (type A) already created
• A Cloudflare API Token with Zone DNS Edit permissions
• jq, curl, and systemd

Installation

Clone the repo and run:

sudo ./install

Alternatively, without cloning:

curl -fsSL https://raw.githubusercontent.com/Edward-Ji/cf-ddns/main/install | sudo bash

The script will:

1. Prompt for your Zone ID, API token, and DNS record name
2. Validate your API token via the /user/tokens/verify endpoint
3. Automatically fetch the DNS Record ID
4. Prompt for TTL, proxying, IP query domain, and update interval
5. Save credentials and config to /etc/cf-ddns/env
6. Install the cf-ddns script and set up a systemd service + timer

To view logs:

journalctl -t cf-ddns

Configuration

All configuration values are stored in:

/etc/cf-ddns/env

This file is sourced by the systemd service. To update any value:

sudo nano /etc/cf-ddns/env
sudo systemctl restart cf-ddns.timer

Uninstallation

To fully remove cf-ddns, run:

sudo ./uninstall

Or if not cloned:

curl -fsSL https://raw.githubusercontent.com/Edward-Ji/cf-ddns/main/uninstall | sudo bash

This will:

• Stop and disable the timer
• Remove the systemd unit files
• Delete the updater script, environment file, and saved IP state