Multiple Django/gunicorn/Nginx sites using different IPv6 addresses on one Droplet

Apart from what has been said, Hosting multiple websites on a single server, each with its own domain and SSL certificate, doesn’t necessarily require multiple IP addresses. This is a common misconception, especially with the advent of Server Name Indication (SNI) which allows a web server to safely host multiple TLS certificates at the same IP address.

Using SNI, the client sends the hostname as part of the TLS handshake, enabling the server to present the correct certificate. Modern web servers like Nginx and web browsers all support SNI.

Here’s how you can set up multiple sites on a single IP in Nginx:

1. Create Separate Server Blocks:

Define a server block for each website in your Nginx configuration. Each server block should specify the domain names it handles and the path to its SSL certificates.

Example for exampleSite1.com:

server {
    listen 443 ssl;
    server_name exampleSite1.com www.exampleSite1.com;

    ssl_certificate /path/to/site1/fullchain.pem;
    ssl_certificate_key /path/to/site1/privkey.pem;

    # The rest of your configuration...
}

Repeat for exampleSite2.com with its own paths to its SSL certificate files.

2. HTTP to HTTPS Redirect:

For each site, include a server block to handle HTTP requests and redirect them to HTTPS.

server {
    listen 80;
    server_name exampleSite1.com www.exampleSite1.com;
    return 301 https://$host$request_uri;
}

Again, repeat this for exampleSite2.com.

3. Nginx Configuration:

Place these server blocks in the appropriate Nginx configuration files (/etc/nginx/sites-available/), and create symbolic links to them in the /etc/nginx/sites-enabled/ directory.

4. DNS Settings:

In your DNS settings (at your domain registrar or DNS provider), point both exampleSite1.com and exampleSite2.com to the same IP address of your server.

5. Obtain SSL Certificates:

You can use Let’s Encrypt to obtain free SSL certificates for both domains. Run Certbot for each domain separately:

sudo certbot --nginx -d exampleSite1.com -d www.exampleSite1.com
sudo certbot --nginx -d exampleSite2.com -d www.exampleSite2.com

Certbot will automatically modify your Nginx configuration to use the obtained certificates.

6. Reload Nginx:

After making changes to the configuration, reload Nginx to apply them:

sudo nginx -t
sudo systemctl reload nginx

Advantages of Using a Single IP:

• Simplifies Configuration: Managing a single IP address is easier than handling multiple IPs for different domains.
• IPv4 Address Conservation: With the scarcity of IPv4 addresses, it’s practical to host multiple sites on one IP.
• SNI Support: Modern clients support SNI, which makes hosting multiple TLS-secured websites on one IP feasible.

By following these steps, you can host multiple SSL-enabled websites on a single server using one IP address. The key is to configure each site in its own server block in Nginx and ensure DNS points all your domains to the same server. This is a standard practice and works well in most hosting environments.

Hey,

Running multiple Django sites using different IPv6 addresses on a single Droplet is an efficient use of resources. However, there are a few things to keep in mind when setting this up. I’ll outline the steps below:

1. For the second site, you’ll need to explicitly set Nginx to listen on the specific IPv6 address assigned to that site, both for HTTP and HTTPS:

   listen [ipv6:address:2]:80 ipv6only=on;
   listen [ipv6:address:2]:443 ssl ipv6only=on;
   

   Replace [ipv6:address:2] with the actual IPv6 address allocated to your second site. This tells Nginx to listen for incoming connections for that site on this specific address.

2. Since you haven’t run Certbot for the second site, you’ll need to configure SSL manually. Assuming you have the SSL certificates ready:

   ssl_certificate /path/to/second/site/fullchain.pem;
   ssl_certificate_key /path/to/second/site/privkey.pem;
   

   These lines should be within the server block that listens on port 443. If you don’t have the certificates yet, you’ll need to obtain them before you can serve the site over HTTPS.

3. Verify Nginx and Domain Configuration:

   • Run nginx -t to test your Nginx configuration for syntax errors.
   • Ensure DNS settings for your second domain are correct and propagated by using a tool like dig or visiting an online DNS checker.
   • Check your domain registrar and DigitalOcean’s networking settings to ensure your AAAA records match the IPv6 address configured in Nginx.

4. Review Logs for Specific Error Messages:

   • Access and error logs for Nginx can offer more insights:

   sudo tail -f /var/log/nginx/error.log
   sudo tail -f /var/log/nginx/access.log
   

   • Look for any messages related to your second site and address any issues that stand out.

5. Confirm that your firewall isn’t blocking connections to the second IPv6 address. If you’re using DigitalOcean’s Cloud Firewall, ensure the rules allow traffic to the second site.

6. If you intend to use Certbot for SSL on the second site, make sure your Droplet is configured to handle IPv6 correctly, as Let’s Encrypt will need to validate your domain over IPv6 if an AAAA record exists.

After addressing these points, reload Nginx to apply any changes

sudo systemctl reload nginx

Changes in DNS can take time to propagate, and you might need to wait a bit before your settings take effect.

Best,

Bobby