Here in the office we add to our hosts file the address of the test site, which resides in the same server that the production site. I would like to be able to have some of our customers to access the test site to get their feed back. Maybe this is very basic but has elude me on my web searches.
The server is in Vultr and responds to both the production server and the test server. The sites names are in this form: and

Thanks for the help