IPv6 DDNS for Cloudflare DNS

A Python script to 🧐 detect changes to the public IPv6 address and 📝 update the corresponding Cloudflare DNS record to point to the new address.

Requirements

• Python (tested on Python 3.8)

Dependencies

• requests Python module

Usage

ddns.py

The DDNS script.

-z, --zone_id: The zone ID of the domain name.

-r, --record_id: The record ID of the DNS record.

-t, --api_token: The API token.

-s, --service: The service to get the IPv6 addresses from. One of icanhazip, ipify, or ipinfo

--ttl: Optional. The desired TTL of the DNS record in seconds. If not specified, the TTL will not be checked or updated.

-v, --verbose: Print the debug messages

Example:

python ddns.py --zone_id 00000000000000000000000000000000 --record_id 00000000000000000000000000000000 --api_token 0000000000000000000000000000000000000000 --service icanhazip --ttl 60

check_dns_record.py

An utility script to check the DNS records of the domain name.

-z, --zone_id: The zone ID of the domain name.

-t, --api_token: The API token.

Example:

python check_dns_record.py --zone_id 00000000000000000000000000000000 --api_token 00000000000000000000000000000000

Quick Start

Add a new DNS record

Add an AAAA record to your domain name with any IPv6 address (as it will be automatically updated by the script later) e.g. 2606:4700:4700::1111.

Get the required token and ID

Go to the API Tokens tab of your Cloudflare profile dashboard and create an API token for your zone (domain name) using the Edit zone DNS template. Take note of the token. It will be passed to the --api_token argument.

Go to the Cloudflare dashboard and click your domain name in the Websites tab. Take note of the zone ID in the API section of the Overview tab. It will be passed to the --zone_id argument.

Use check_dns_record.py to check the DNS records of the domain name. Look for the newly created AAAA record and take note of its id. It will be passed to the --record_id argument.

Configure crontab to run the DDNS script periodically

Create a new shell script ddns.sh. Set the arguments to the desired values. Use the absolute path to ddns.py. Example:

python /abs/path/to/ddns.py --zone_id 00000000000000000000000000000000 --record_id 00000000000000000000000000000000 --api_token 0000000000000000000000000000000000000000 --service icanhazip --ttl 60

To keep a log of the output of the script, use the following line instead:

python /abs/path/to/ddns.py --zone_id 00000000000000000000000000000000 --record_id 00000000000000000000000000000000 --api_token 0000000000000000000000000000000000000000 --service icanhazip --ttl 60 >> /abs/path/to/ddns.log 2>&1

In the terminal, edit crontab by running:

crontab -e

Add the following line to the bottom of the file and save to run the DDNS script every 5 minutes:

*/5 * * * * bash /abs/path/to/ddns.sh