If my servers base domain is "xxx.com" and now I'm developing a site for a customer for their domain "yyy.com" which is hosted elsewhere publicly but set up in my ISPConfig as a site. How do I create a preview adress for this one going like this: "yyy.com.preview.xxx.com"? Of curse I can do this in the hosts-file but for some client's, especially if there is a team this is hard. And sometimes they also forget to change it back when it goes live which creates big problems. So, how do I set up an automatic preview adress for the sites I'm developing?