Configuring IP Address Check Services for Dynamic DNS¶

pfSense® software supports custom IP address check services. These services are used by Dynamic DNS clients to determine the public IP address of the firewall when a WAN interface is behind an upstream NAT device.

To create or edit one of these services, navigate to Services > Dynamic DNS on the Check IP Services tab.

Settings¶

The following settings are available for a service entry:

Enable: Allow this service to be used by Dynamic DNS clients.
Name: A short name to identify this service.
URL: The full URL to the IP address check page.
Username/Password: Optional authentication to use when accessing the URL.
Verify SSL Peer: Check this box if the server has a self-signed SSL certificate or a certificate from a CA that is not trusted by the firewall.
Description: A longer description of this service.

Once a service is defined, it may be selected on individual Dynamic DNS service entries.

Server-Side Configuration Examples¶

Hosting one of these services is very simple. The server page need only print the requesting client IP address in the expected format:

Current IP Address: x.x.x.x

nginx (internal/native)¶

location /ip {
    default_type text/html;
    return 200 "<html><head><title>Current IP Check</title></head><body>Current IP Address: $remote_addr</body></html>";
}

nginx (internal with LUA)¶

location = /ip {
    default_type text/html;
    content_by_lua '
        ngx.say("<html><head><title>Current IP Check</title></head><body>Current IP Address: ")
        ngx.say(ngx.var.remote_addr)
        ngx.say("</body></html>")
    ';
}

PHP¶

<html>
     <head>
             <title>Current IP Check</title>
     </head>
     <body>
             Current IP Address: <?=$_SERVER['REMOTE_ADDR']?>
     </body>
</html>