The DNS is configured in a way that all 3 go to the same Joomla installation/directory. In Joomla I would like to cath which domain is requested, so I can show the right page/article for that specific domain.
I have used Option #3: Create a PHP Header Redirect, for multiple domains with specific domain redirects for custom templates
The problem with this option is that the URL is changed, where I would like to pass the unique identifier or the variable if you will silently. So, the visitor should still only see the original UTL that he used.
So, is it possible to silently pass a identifier or a variable to my Joomla system to identify the right domain and correspnsing article, withour showing this to the visitor on the URL.