Setting Up Dynamic DNS on a Raspberry Pi for Self-Hosting

What is Dynamic DNS?

Dynamic DNS (DDNS) is a service that maps your dynamic public IP address to a domain name. This is useful when hosting services like WordPress, Ghost, or an Nginx server at home, as it allows you to access your Raspberry Pi using a consistent domain name, even if your ISP changes your IP address.

Why Use Dynamic DNS for Self-Hosting?

1. Consistent Access: A DDNS service keeps your domain name updated with your public IP address.
2. Ease of Use: No need to remember changing IP addresses.
3. Remote Access: Makes self-hosted services accessible from anywhere.

Prerequisites

1. A Raspberry Pi running Raspberry Pi OS.
2. A registered account with a DDNS provider (e.g., No-IP, DuckDNS, DynDNS).
3. Your Raspberry Pi must be accessible from the internet via port forwarding.
4. A domain name (if required by your DDNS provider).

Setting Up a DDNS Client on Raspberry Pi

Step 1: Choose a DDNS Provider

Popular free and paid DDNS providers include:

• No-IP
• DuckDNS
• DynDNS

Create an account with your preferred provider and configure a hostname. For example, myhome.ddns.net.

Step 2: Install a DDNS Client

Depending on your chosen provider, you’ll need to install a DDNS client. For this guide, we’ll cover No-IP and DuckDNS.

Option 1: Setting Up No-IP

1. Install the No-IP Client:

   sudo apt update
   sudo apt install noip2
   

2. Configure No-IP:

   Run the following command and enter your No-IP account details when prompted:

   sudo noip2 -C
   

3. Start the No-IP Client:

   After configuring, start the client with:

   sudo noip2
   

4. Check the Status:

   Verify that the No-IP client is running:

   sudo noip2 -S
   

Option 2: Setting Up DuckDNS

1. Install DuckDNS Client:

   DuckDNS doesn’t require a specific client. Instead, use a script. Navigate to your home directory:

   cd ~
   

2. Download the DuckDNS Script:

   Create a script file:

   nano duckdns.sh
   

   Add the following content, replacing <TOKEN> and <DOMAIN> with your DuckDNS token and subdomain:

   echo url="https://www.duckdns.org/update?domains=<DOMAIN>&token=<TOKEN>&ip=" | curl -k -o ~/duckdns.log -K -
   

3. Make the Script Executable:

   chmod +x duckdns.sh
   

4. Automate Updates with Cron:

   Open the crontab editor:

   crontab -e
   

   Add the following line to run the script every 5 minutes:

   */5 * * * * ~/duckdns.sh
   

Configuring Your Router

Step 1: Enable Port Forwarding

Log in to your router’s admin interface and forward the following ports to your Raspberry Pi’s local IP:

• Port 80 (HTTP) for web servers like WordPress or Ghost.
• Port 443 (HTTPS) for secure web access.
• Any other ports required by your application.

Step 2: Test Access

Use your DDNS domain (e.g., http://myhome.ddns.net) to access your Raspberry Pi from an external network. If configured correctly, your DDNS domain should point to your Raspberry Pi’s public IP address.

Additional Security: SSL/TLS Certificates with Let’s Encrypt

1. Install Certbot:

   Install Certbot to obtain free SSL certificates:

   sudo apt update
   sudo apt install certbot python3-certbot-nginx
   

2. Obtain a Certificate:

   Run the following command, replacing <DOMAIN> with your DDNS domain:

   sudo certbot --nginx -d <DOMAIN>
   

3. Renew Certificates Automatically:

   Add a cron job to renew the certificates automatically:

   crontab -e
   

   Add this line:

   0 3 * * * certbot renew --quiet
   

Conclusion

Setting up Dynamic DNS on your Raspberry Pi allows you to self-host services like WordPress, Ghost, or an Nginx server with a consistent domain name. With DDNS and port forwarding, your Raspberry Pi becomes a powerful tool for hosting accessible, secure applications.