Mark Caudill


Cloudflare Dynamic DNS Updater

Category: misc
#!/usr/bin/env python

import argparse                                                                                                       
import CloudFlare                                          
import logging                                             
import requests

def public_ip(service=''):                                                                           
    Get the apparent public IP of this computer. This does not imply that the
    necessary network configurations are in place to allow public access.

    Raises Exceptions for anything but a 200 response.

    :param service: the url to perform a GET against (should return only an IP)
    :type  service: str
    :returns: this machine's IP as seen by a server on the Internet
    :rtype: str
    logging.debug("Looking up public IP")
    r = requests.get(service)
    logging.debug("Found " + r.text)
    return r.text

def update_cf_dns(cf, name, ip_address):
    # 'AAAA' for IPv6, 'A' for IPv4 (default)
    if ':' in ip_address:
        ip_address_type = 'AAAA'
        ip_address_type = 'A'
    logging.debug("Address type " + ip_address_type)

    # Get the Zone ID
    logging.debug("Looking up zone id for " + name)        
     for zone in cf.zones.get():
         if '.'.join(name.split('.')[-2:]) in zone['name']:
             zone_id = zone['id']
             logging.debug("Found " + zone_id)
         raise Exception("Unable to find zone id for " + name)

     # Get the DNS record
     logging.debug("Fetching DNS record")
     dns_record = cf.zones.dns_records.get(zone_id,
             params={'name': name, 'match': 'all', 'type': ip_address_type})[0]
     logging.debug("Found " + dns_record['id'])

     # Check to see if the IP has changed
     if dns_record['content'] != ip_address:"Performing DSN record update", dns_record['content'],
                 "->", ip_address)
         cf.zones.dns_records.put(zone_id, dns_record['id'],
                 data={'name': name,
                       'type': ip_address_type,
                       'content': ip_address})
         logging.debug("Old Address:" + dns_record['content'] +
                 "New Address:" + ip_address)"Not updating")

         def main():
             parser = argparse.ArgumentParser()
             parser.add_argument('--email', type=str, required=True)
             parser.add_argument('--token', type=str, required=True)
             parser.add_argument('--domain', type=str, required=True,
                     help='the domain name to update')
             args = parser.parse_args()
             logging.basicConfig(format='%(asctime)s %(message)s',
             cf = CloudFlare.CloudFlare(, token=args.token)
             update_cf_dns(cf, args.domain, public_ip())

         if __name__ == '__main__':

You can then invoke it with a cron job:

*/15 * * * *  /root/ --email cfemail@domain.tld --token TOKEN --domain 2>&1 | logger -t ""