It is not clear to me what you want to do. Do you want to map the connectivitycheck.gstatic.com domain name to a local IP? And the local IP leads to a web server that will provide some reply to the requesting client?
It is not clear to me what you want to do. Do you want to map the connectivitycheck.gstatic.com domain name to a local IP? And the local IP leads to a web server that will provide some reply to the requesting client?