To allow IPv6 and IPv4 addresses in Nginx, you’ll need to modify your Nginx configuration file appropriately. Here’s how you can allow the UptimeMonster IP addresses 2a01:4f8:c012:9c4a::1 (IPv6) and 162.55.41.109 (IPv4):

1. Access the Nginx Configuration File

Open your Nginx configuration file using a text editor. This could be the main nginx.conf file or a specific site configuration file under /etc/nginx/sites-available/.

sudo nano /etc/nginx/nginx.conf

Or for a specific site configuration file:

sudo nano /etc/nginx/sites-available/your-site.conf

2. Add IP Allow Rules

Within the appropriate server block or location block in your configuration file, add the allow directives for the specified IPv6 and IPv4 addresses.

server {
    listen 80;
    server_name your-domain.com;

    location / {
        # Allow specific IPv6 address
        allow 2a01:4f8:c012:9c4a::1;

        # Allow specific IPv4 address
        allow 162.55.41.109;

        # Deny all other IP addresses
        deny all;

        # Your other location directives
        try_files $uri $uri/ =404;
    }
}

3. Save and Close the Configuration File

After adding the allow directives for the IP addresses, save the changes and close the editor. In nano, press CTRL + X, then Y to confirm, and Enter to save.

4. Test the Nginx Configuration

It’s important to check the syntax of your Nginx configuration files to ensure there are no errors:

sudo nginx -t

If the test is successful, you should see a message indicating that the configuration file test is successful.

5. Reload Nginx to Apply Changes

Finally, reload Nginx to apply the new configuration:

sudo systemctl reload nginx

Or, for older systems using init.d:

sudo service nginx reload