gandi-live-dns

This is a simple dynamic DNS updater for the Gandi registrar. It uses their LiveDNS REST API to update the zone file for a subdomain of a domain to point at the external IPv4 address of the computer it has been run from.

It has been developed on Debian 8 Jessie and tested on Debian 9 Stretch GNU/Linux using Python 2.7.

This has been update to work with Python 3 (Python 3.6 at Ubuntu 18.04). This will not work with Python 2 since it will be deprecated in is deprecated since 2020-01-01.

With the new v5 Website, Gandi has also launched a new REST API which makes it easier to communicate via bash/curl or python/requests.

Goal

You want your homeserver to be always available at dynamic_subdomain.mydomain.tld.

Debian Package Requirements

apt-get update && apt-get upgrade && apt-get install unzip python-requests python-args python-simplejson

API Key

First, you must apply for an API key with Gandi. Visit https://account.gandi.net/en/ and apply for (at least) the production API key by following their directions.

A DNS Record

Create the DNS A Records in the GANDI Webinterface which you want to update if your IPv4 changes.

AAAA DNS Record (only needed if ipv6 is in use)

Create the DNS AAAA Records for ipv6 in the GANDI Webinterface which you want to update if your IPv6 changes.

Git Clone or Download the Script

Download the Script from here as zip/tar.gz and extract it.

or clone from git

git clone https://github.com/cavebeat/gandi-live-dns.git

Script Configuration

Then you'd need to configure the script in the src directory. Copy example.config.py to config.py, and put it in the same directory as the script.

Edit the config file to fit your needs.

api_secret

Start by retrieving your API Key from the "Security" section in new Gandi Account admin panel to be able to make authenticated requests to the API. api_secret = '---my_secret_API_KEY----'

api_endpoint

Gandiv5 LiveDNS API Location http://doc.livedns.gandi.net/#api-endpoint

api_endpoint = 'https://dns.api.gandi.net/api/v5'

dnsentries

Your domains and subdomains (IPv4 and IPv6) to update

dnsentries = {
    "mydomain.tld": {
        "ipv4": ["subdomain1", "subdomain2"],
        "ipv6": ["subdomain3v6"],
        },
    "myotherdomain.tld": {
        "ipv4": ["subdomain4"],
        },
}

subdomains

All subdomains which should be updated. They get created if they do not yet exist.

• subdomains for ipv4
• subdomains6 for ipv6

subdomains = ["subdomain1", "subdomain2", "subdomain3"]
subdomains6 = ["subdomain1v6", "subdomain2v6", "subdomain3v6"]

The first subdomain is used to find out the actual IP in the Zone Records. If the returnded ip from is ipv6, it will use the first from subdomains6.

Run the script

And run the script:

root@dyndns:~/gandi-live-dns-master/src# ./gandi-live-dns.py   
Checking dynamic IP:  127.0.0.1
Checking IP from DNS Record subdomain1:  127.0.0.1
IP Address Match - no further action

If your IP has changed, it will be detected and the update will be triggered.

root@dyndns:~/gandi-live-dns-master/src# ./gandi-live-dns.py
Checking dynamic IP:  127.0.0.2
Checking IP from DNS Record subdomain1:  127.0.0.1
IP Address Mismatch - going to update the DNS Records for the subdomains with new IP 127.0.0.2
Status Code: 201 , DNS Record Created , IP updated for subdomain1
Status Code: 201 , DNS Record Created , IP updated for subdomain2
Status Code: 201 , DNS Record Created , IP updated for subdomain3

Command Line Arguments

root@dyndns:~/gandi-live-dns-master/src# ./gandi-live-dns.py -h
usage: gandi-live-dns.py [-h] [-f] [-v] [-r]

optional arguments:
  -h, --help            show this help message and exit
  -v, --verbose         increase output verbosity
  -f, --force           force an update/create
  -r REPEAT, --repeat REPEAT
                        keep running and repeat every N seconds

The force option runs the script, even when no IP change has been detected. It will update all subdomains and even create them if they are missing in the Zone File/Zone UUID. This can be used if additional/new subdomains get appended to the conig file.

IP address lookup service

There exist several providers for this case, but better is to run your own somewhere.

Poor Mans PHP Solution

On a LAMP Stack, place the file index.php in a directory /ip in your webroot.

root@laptop:~# curl https://blog.cavebeat.org/ip/
127.0.0.1

This should fit your personal needs and you still selfhost the whole thing.

IP address lookup service https://ifconfig.co

https://github.com/mpolden/ipd A simple service for looking up your IP address. This is the code that powers https://ifconfig.co

use external services

choose one as described in the config file.

Cron the script

Run the script every five minutes.

*/5 * * * * /root/gandi-live-dns-master/src/gandi-live-dns.py >/dev/null 2>&1 

Run with Docker

Use the docker file to build the image. With docker, the script will run every 3600 seconds. (This value can be changed in the Dockerfile.

Limitations

The XML-RPC API has a limit of 30 requests per 2 seconds, so i guess it's safe to update 25 subdomains at once with the REST API.

Upcoming Features

• command line Argument for verbose mode Aditional verbosity implemented.

Inspiration

This DynDNS updater is inspired by https://github.com/jasontbradshaw/gandi-dyndns which worked very well with the classic DNS from Gandiv4 Website and their XML-RPC API.

Gandi has created a new API, i accidently switched to the new DNS Record System, so someone had to start a new updater.