Lightweight universal DDNS Updater with Docker and web UI

Light container updating DNS A and/or AAAA records periodically for multiple DNS providers

Features

• Updates periodically A records for different DNS providers:
  • Cloudflare
  • DDNSS.de
  • DigitalOcean
  • DonDominio
  • DNSOMatic
  • DNSPod
  • Dreamhost
  • DuckDNS
  • DynDNS
  • FreeDNS
  • Gandi
  • GoDaddy
  • Google
  • He.net
  • Infomaniak
  • Linode
  • LuaDNS
  • Namecheap
  • NoIP
  • Njalla
  • OpenDNS
  • OVH
  • Selfhost.de
  • Spdyn
  • Strato.de
  • Want more? Create an issue for it!
• Web User interface

• 14MB Docker image based on a Go static binary in a Scratch Docker image with ca-certificates and timezone data
• Persistence with a JSON file updates.json to store old IP addresses with change times for each record
• Docker healthcheck verifying the DNS resolution of your domains
• Highly configurable
• Sends notifications to your Android phone, see the Gotify section (it's free, open source and self hosted 🆒)
• Compatible with amd64, 386, arm64, arm32v7 (Raspberry Pis) CPU architectures.

Setup

The program reads the configuration from a JSON object, either from a file or from an environment variable.

1. Create a directory of your choice, say data with a file named config.json inside:

   mkdir data
   touch data/config.json
   # Owned by user ID of Docker container (1000)
   chown -R 1000 data
   # all access (for creating json database file data/updates.json)
   chmod 700 data
   # read access only
   chmod 400 data/config.json

   (You could change the user ID, for example with 1001, by running the container with --user=1001)

2. Write a JSON configuration in data/config.json, for example:

   {
       "settings": [
           {
               "provider": "namecheap",
               "domain": "example.com",
               "host": "@",
               "password": "e5322165c1d74692bfa6d807100c0310"
           }
       ]
   }

   You can find more information in the configuration section to customize it.

3. Run the container with

   docker run -d -p 8000:8000/tcp -v "$(pwd)"/data:/updater/data qmcgaw/ddns-updater

4. (Optional) You can also set your JSON configuration as a single environment variable line (i.e. {"settings": [{"provider": "namecheap", ...}]}), which takes precedence over config.json. Note however that if you don't bind mount the /updater/data directory, there won't be a persistent database file /updater/updates.json but it will still work.

Next steps

You can also use docker-compose.yml with:

docker-compose up -d

You can update the image with docker pull qmcgaw/ddns-updater. Other Docker image tags are available.

Configuration

Start by having the following content in config.json, or in your CONFIG environment variable:

{
    "settings": [
        {
            "provider": "",
        },
        {
            "provider": "",
        }
    ]
}

For each setting, you need to fill in parameters. Check the documentation for your DNS provider:

• Cloudflare
• DDNSS.de
• DigitalOcean
• DonDominio
• DNSOMatic
• DNSPod
• Dreamhost
• DuckDNS
• DynDNS
• DynV6
• FreeDNS
• Gandi
• GoDaddy
• Google
• He.net
• Infomaniak
• Linode
• LuaDNS
• Namecheap
• NoIP
• Njalla
• OpenDNS
• OVH
• Selfhost.de
• Spdyn
• Strato.de

Note that:

• you can specify multiple hosts for the same domain using a comma separated list. For example with "host": "@,subdomain1,subdomain2",.

Environment variables

Environment variable	Default	Description
CONFIG		One line JSON object containing the entire config (takes precendence over config.json file) if specified
PERIOD	5m	Default period of IP address check, following this format
PUBLICIP_FETCHERS	all	Comma separated fetcher types to obtain the public IP address from http and dns
PUBLICIP_HTTP_PROVIDERS	all	Comma separated providers to obtain the public IP address (ipv4 or ipv6). See the Public IP section
PUBLICIPV4_HTTP_PROVIDERS	all	Comma separated providers to obtain the public IPv4 address only. See the Public IP section
PUBLICIPV6_HTTP_PROVIDERS	all	Comma separated providers to obtain the public IPv6 address only. See the Public IP section
PUBLICIP_DNS_PROVIDERS	all	Comma separated providers to obtain the public IP address (IPv4 and/or IPv6). See the Public IP section
UPDATE_COOLDOWN_PERIOD	5m	Duration to cooldown between updates for each record. This is useful to avoid being rate limited or banned.
HTTP_TIMEOUT	10s	Timeout for all HTTP requests
LISTENING_PORT	8000	Internal TCP listening port for the web UI
ROOT_URL	/	URL path to append to all paths to the webUI (i.e. /ddns for accessing https://example.com/ddns through a proxy)
BACKUP_PERIOD	0	Set to a period (i.e. 72h15m) to enable zip backups of data/config.json and data/updates.json in a zip file
BACKUP_DIRECTORY	/updater/data	Directory to write backup zip files to if BACKUP_PERIOD is not 0.
LOG_LEVEL	info	Level of logging, info, warning or error
LOG_CALLER	hidden	Show caller per log line, hidden or short
GOTIFY_URL		(optional) HTTP(s) URL to your Gotify server
GOTIFY_TOKEN		(optional) Token to access your Gotify server
TZ		Timezone to have accurate times, i.e. America/Montreal

Public IP

By default, all public IP fetching types are used and cycled (over DNS and over HTTPs).

On top of that, for each fetching method, all echo services available are cycled on each request.

This allows you not to be blocked for making too many requests.

You can otherwise customize it with the following:

• PUBLICIP_HTTP_PROVIDERS gets your public IPv4 or IPv6 address. It can be one or more of the following:
  • opendns using https://diagnostic.opendns.com/myip
  • ifconfig using https://ifconfig.io/ip
  • ipinfo using https://ipinfo.io/ip
  • ddnss using https://ddnss.de/meineip.php
  • google using https://domains.google.com/checkip
  • You can also specify an HTTPS URL such as https://ipinfo.io/ip
• PUBLICIPV4_HTTP_PROVIDERS gets your public IPv4 address only. It can be one or more of the following:
  • ipify using https://api.ipify.org
  • noip using http://ip1.dynupdate.no-ip.com
  • You can also specify an HTTPS URL such as https://ipinfo.io/ip
• PUBLICIPV6_HTTP_PROVIDERS gets your public IPv6 address only. It can be one or more of the following:
  • ipify using https://api6.ipify.org
  • noip using http://ip1.dynupdate6.no-ip.com
  • You can also specify an HTTPS URL such as https://ipinfo.io/ip
• PUBLICIP_DNS_PROVIDERS gets your public IPv4 address only or IPv6 address only or one of them (see #136). It can be one or more of the following:
  • google
  • cloudflare

Host firewall

If you have a host firewall in place, this container needs the following ports:

• TCP 443 outbound for outbound HTTPS
• TCP 80 outbound if you use a local unsecured HTTP connection to your Gotify server
• UDP 53 outbound for outbound DNS resolution
• TCP 8000 inbound (or other) for the WebUI

Architecture

At program start and every period (5 minutes by default):

1. Fetch your public IP address
2. For each record:
   1. DNS resolve it to obtain its current IP address(es)
      • If the resolution fails, update the record with your public IP address by calling the DNS provider API and finish
   2. Check if your public IP address is within the resolved IP addresses
      • Yes: skip the update
      • No: update the record with your public IP address by calling the DNS provider API

💡 We do DNS resolution every period so it detects a change made to the record manually, for example on the DNS provider web UI 💡 As DNS resolutions are essentially free and without rate limiting, these are great to avoid getting banned for too many requests.

Special case: Cloudflare

For Cloudflare records with the proxied option, the following is done.

At program start and every period (5 minutes by default), for each record:

1. Fetch your public IP address
2. For each record:
   1. Check the last IP address (persisted in updates.json) for that record
      • If it doesn't exist, update the record with your public IP address by calling the DNS provider API and finish
   2. Check if your public IP address matches the last IP address you updated the record with
      • Yes: skip the update
      • No: update the record with your public IP address by calling the DNS provider API

This is the only way as doing a DNS resolution on the record will give the IP address of a Cloudflare server instead of your server.

⚠️ This has the disadvantage that if the record is changed manually, the program will not detect it. We could do an API call to get the record IP address every period, but that would get you banned especially with a low period duration.

Gotify

Gotify is a simple server for sending and receiving messages, and it is free, private and open source

• It has an Android app to receive notifications
• The app does not drain your battery 👍
• The notification server is self hosted, see how to set it up with Docker
• The notifications only go through your own server (ideally through HTTPS though)

To set it up with DDNS updater:

1. Go to the Web GUI of Gotify
2. Login with the admin credentials
3. Create an app and copy the generated token to the environment variable GOTIFYTOKEN (for this container)
4. Set the GOTIFYURL variable to the URL of your Gotify server address (i.e. http://127.0.0.1:8080 or https://bla.com/gotify)

Testing

• The automated healthcheck verifies all your records are up to date using DNS lookups
• You can also manually check, by:
  1. Going to your DNS management webpage
  2. Setting your record to 127.0.0.1
  3. Run the container
  4. Refresh the DNS management webpage and verify the update happened

Development and contributing

• Contribute with code
• Github workflows to know what's building
• List of issues and feature requests
• Kanban board

License

This repository is under an MIT license

Used in external projects

• Starttoaster/docker-traefik

Support

Sponsor me on Github or donate to paypal.me/qmcgaw

Many thanks to J. Famiglietti for supporting me financially 🥇👍