On a generic POSIX-like system in order to give a system an alias that is not provided by the upstream DNS-server you would modify the etc/hosts file. eg. you include something like this at the end:
where 255.255.255.255 is the IP-adres of a server responding with the intended website of the not yet published alias of said website.
On whonix modifying the etc/hosts file does not give the expected result. This holds true for modifications to either the workstation or gateway machine. I am sure this has something to do with the insulation of these virtual machines from the DNS of the host machine, which, of course, is a good feature. However to get the desired result I would like to know how whonix handles these matters i.e. I would like to know which file I have to modify to include a entry such as the one from my example.