Is it possible to temporarily disable IPv4 connections on a web server to test IPv6 functionality in PHP scripts?

To temporarily disable IPv4 connections on a web server to test IPv6 functionality in PHP scripts, you can modify the server configuration to only allow IPv6 connections. This can be done by configuring the server to listen only on the IPv6 address. This way, any incoming connections will need to use IPv6.

// Disable IPv4 connections by setting the server to only listen on the IPv6 address
$server->listen('[::]:80');