How to use php cross-domain cookie sharing_PHP tutorial

The domain where machine A is located: a1.main.com, A has application main.php
The domain where machine B is located: b1.test.com, B has application test.php

1. When setting cookies in main.php, the cookie setting method is as follows:

2. When entering the url to access test, you must enter the domain name for resolution.
For example, enter: http://b1.test.com/test.php to get the cookie set by cas on the client.
And machine B accesses the local application, enter: http://localhost: 8080/test.php cannot obtain cookies.