#+date: <2024-03-15>
#+title: Self-Hosting DDNS Updater
#+description:
#+slug: self-hosting-ddns-updater

#+caption: DDNS Updater Web View
[[https://media.githubusercontent.com/media/ccleberg/img/main/blog/20240315-ddns-updater/ddns.png]]

[[https://github.com/qdm12/ddns-updater][DDNS Updater]] is a program to keep DNS A and/or AAAA records updated for multiple
DNS providers.

If you've read any of my other posts, you'll notice that I have been searching
for and using a few different DDNS updating solutions for years. You'll also
notice that I love any projects that offer a Docker Compose solution.

Luckily, DDNS Upater fits both of these preferences.

** Installation

To get started, always make sure to review the project's [[https://github.com/qdm12/ddns-updater/blob/master/README.md][README]]. I'll be
documenting my steps below, but they may have changed by the time you read this.

The first step is to set up the directories and files required for the project.

#+begin_src sh
mkdir ~/ddns-updater
mkdir ~/ddns-updater/data
touch ~/ddns-updater/data/config.json
#+end_src

*** Configuration

The main configuration you need to update is the =data/config.json= file. There
is a large list of supported providers in the README, but I'm going to use
Cloudflare in this example.

#+begin_src sh
nano ~/ddns-updater/data/config.json
#+end_src

When setting up the configuration for Cloudflare, you'll need the following:

- Required Parameters
  - ="zone_identifier"= is the Zone ID of your site from the domain overview
    page
  - ="host"= is your host and can be ="@"=, a subdomain or the wildcard ="*"=.
    See [[https://github.com/qdm12/ddns-updater/issues/243#issuecomment-928313949][this issue comment for context]].
  - ="ttl"= integer value for record TTL in seconds (specify 1 for automatic)
  - One of the following ([[https://developers.cloudflare.com/fundamentals/api/get-started/][how to find API keys]]):
    - Email ="email"= and Global API Key ="key"=
    - User service key ="user_service_key"=
    - API Token ="token"=, configured with DNS edit permissions for your DNS
      name's zone
- Optional Parameters
  - ="proxied"= can be set to =true= to use the proxy services of Cloudflare
  - ="ip_version"= can be =ipv4= (A records), or =ipv6= (AAAA records) or =ipv4
    or ipv6= (update one of the two, depending on the public ip found). It
    defaults to =ipv4 or ipv6=.
  - ="ipv6_suffix"= is the IPv6 interface identifier suffix to use. It can be
    for example =0:0:0:0:72ad:8fbb:a54e:bedd/64=. If left empty, it defaults to
    no suffix and the raw public IPv6 address obtained is used in the record
    updating.

#+begin_src conf
{
  "settings": [
    {
      "provider": "cloudflare",
      "zone_identifier": "some id",
      "domain": "domain.com",
      "host": "@",
      "ttl": 1,
      "proxied": true,
      "token": "yourtoken",
      "ip_version": "ipv4",
      "ipv6_suffix": ""
    }
  ]
}
#+end_src

Once you have configured the provider of your choice, correct the file and
directory permissions and ownership.

#+begin_src sh
cd ~/ddns_updater
# 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
#+end_src

*** Docker Compose

After creating the project structure, let's create the =docker-compose.yml=
file.

#+begin_src sh
nano ~/ddns_-pdater/docker-compose.yml
#+end_src

#+begin_src config
version: "3.7"
services:
  ddns-updater:
    image: qmcgaw/ddns-updater
    container_name: ddns-updater
    network_mode: bridge
    ports:
      - 8097:8000/tcp # Change the 8097 value to whichever port you want to use
    volumes:
      - ./data:/updater/data
    environment:
      - CONFIG=
      - PERIOD=5m
      - UPDATE_COOLDOWN_PERIOD=5m
      - PUBLICIP_FETCHERS=all
      - PUBLICIP_HTTP_PROVIDERS=all
      - PUBLICIPV4_HTTP_PROVIDERS=all
      - PUBLICIPV6_HTTP_PROVIDERS=all
      - PUBLICIP_DNS_PROVIDERS=all
      - PUBLICIP_DNS_TIMEOUT=3s
      - HTTP_TIMEOUT=10s

      # Web UI
      - LISTENING_ADDRESS=:8000
      - ROOT_URL=/

      # Backup
      - BACKUP_PERIOD=0 # 0 to disable
      - BACKUP_DIRECTORY=/updater/data

      # Other
      - LOG_LEVEL=info
      - LOG_CALLER=hidden
      - SHOUTRRR_ADDRESSES=
    restart: always
#+end_src

After configuring your preferences in the =docker-compose.yml=, launch the
container.

#+begin_src sh
cd ~/ddns-updater
sudo docker-compose up -d
#+end_src

If you've launched this on your local machine, you can launch =localhost:8097=
in your browser to see the results.

*** Nginx Reverse Proxy

If you launched this service on a server, other machine, or just want to access
it remotely via a domain name, you can use Nginx as a reverse proxy to expose
the service publicly.

Start by creating the Nginx configuration file.

#+begin_src sh
sudo nano /etc/nginx/sites-available/ddns
#+end_src

Here's a basic example that should work properly.

#+begin_src conf
server {
    # If using 443, remember to include your ssl_certificate
    # and ssl_certificate_key
    listen [::]:80;
    listen 80;
    server_name ddns.example.com;

    location / {
        set $upstream_ao http://127.0.0.1:9380;
        proxy_pass $upstream_ao;

        # May need some additional proxy_* parameters,
        # see the full example below if necessary
    }
}
#+end_src

Here's a full example that uses my Authelia authentication service to require
authentication before someone can access the web page.

#+begin_src conf
server {
    if ($host ~ ^[^.]+\.example\.com$) {
        return 301 https://$host$request_uri;
    }

    listen [::]:80;
    listen 80;
    server_name ddns.example.com;
    return 404;
}

server {
    listen [::]:443 ssl http2;
    listen 443 ssl http2;
    server_name ddns.example.com;
    access_log  /var/log/nginx/ddns.access.log;
    error_log   /var/log/nginx/ddns.error.log;

    add_header X-Content-Type-Options "nosniff";
    add_header X-XSS-Protection "1; mode=block";
    add_header X-Frame-Options "DENY";
    add_header Strict-Transport-Security "max-age=63072000; includeSubDomains";
    add_header Referrer-Policy "no-referrer";

    ssl_certificate /etc/letsencrypt/live/example.com/fullchain.pem;
    ssl_certificate_key /etc/letsencrypt/live/example.com/privkey.pem;
    include /etc/letsencrypt/options-ssl-nginx.conf;
    ssl_dhparam /etc/letsencrypt/ssl-dhparams.pem;

    location /authelia {
        internal;
        set $upstream_authelia http://127.0.0.1:9091/api/verify; #change the IP and Port to match the IP and Port of your Authelia container
        proxy_pass_request_body off;
        proxy_pass $upstream_authelia;
        proxy_set_header Content-Length "";

        # Timeout if the real server is dead
        proxy_next_upstream error timeout invalid_header http_500 http_502 http_503;
        client_body_buffer_size 128k;
        proxy_set_header Host $host;
        proxy_set_header X-Original-URL $scheme://$http_host$request_uri;
        proxy_set_header X-Real-IP $remote_addr;
        proxy_set_header X-Forwarded-For $remote_addr;
        proxy_set_header X-Forwarded-Proto $scheme;
        proxy_set_header X-Forwarded-Host $http_host;
        proxy_set_header X-Forwarded-Uri $request_uri;
        proxy_set_header X-Forwarded-Ssl on;
        proxy_redirect  http://  $scheme://;
        proxy_http_version 1.1;
        proxy_set_header Connection "";
        proxy_cache_bypass $cookie_session;
        proxy_no_cache $cookie_session;
        proxy_buffers 4 32k;

        send_timeout 5m;
        proxy_read_timeout 240;
        proxy_send_timeout 240;
        proxy_connect_timeout 240;
    }

    location / {
        set $upstream_ddns http://127.0.0.1:8097; #change ddns to match your container name: $upstream_some-container-name or $upstream_somecontainername
        proxy_pass $upstream_ddns; #change ddns to match your container name: $upstream_some-container-name or $upstream_somecontainername

        auth_request /authelia;
        auth_request_set $target_url https://$http_host$request_uri;
        auth_request_set $user $upstream_http_remote_user;
        auth_request_set $email $upstream_http_remote_email;
        auth_request_set $groups $upstream_http_remote_groups;
        proxy_set_header Remote-User $user;
        proxy_set_header Remote-Email $email;
        proxy_set_header Remote-Groups $groups;

        error_page 401 =302 https://auth.example.com/?rd=$target_url; #change this to match your authentication domain/subdomain

        client_body_buffer_size 128k;

        proxy_next_upstream error timeout invalid_header http_500 http_502 http_503;

        send_timeout 5m;
        proxy_read_timeout 360;
        proxy_send_timeout 360;
        proxy_connect_timeout 360;

        proxy_set_header Host $host;
        proxy_set_header Upgrade $http_upgrade;
        proxy_set_header Connection upgrade;
        proxy_set_header Accept-Encoding gzip;
        proxy_set_header X-Real-IP $remote_addr;
        proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
        proxy_set_header X-Forwarded-Proto $scheme;
        proxy_set_header X-Forwarded-Host $http_host;
        proxy_set_header X-Forwarded-Uri $request_uri;
        proxy_set_header X-Forwarded-Ssl on;
        proxy_redirect  http://  $scheme://;
        proxy_http_version 1.1;
        proxy_set_header Connection "";
        proxy_cache_bypass $cookie_session;
        proxy_no_cache $cookie_session;
        proxy_buffers 64 256k;

        # set_real_ip_from 192.168.1.0/16; #make sure this matches your network setup
        # real_ip_header CF-Connecting-IP;
        # real_ip_recursive on;
    }
}
#+end_src

When complete, simply link the file and restart the web server.

#+begin_src sh
sudo ln -s /etc/nginx/sites-available/ddns /etc/nginx/sites-enabled/ddns
sudo systemctl restart nginx.service
#+end_src

Your ddns-updater service will now be available via =ddns.example.com=!