Hi, the website on my local machine is done and ready to be moved to online server. After reading other people's questions/answers/posts/comments/opinions - I think it shouldn't be a big deal. Though since I'm doing it for very first time I expect some "sudden" issues. Even the website doesn't have a lot of traffic, I would like to avoid messages visitor can get, like "Page not found" or something. And because of website owner too - he's not going to like the message for a couple of hours, or even more.
Right now old website is visible (live) and to replace it with new one I have to remove it. Now, my question is: How do I make "The site is temporarily down for upgrades" message on screen WHILE upgrading the website? Is it possible to create a file, something like "under_maintenance.html", with the message in it, and redirect all visitors to that page using .htaccess? But it shouldn't compromise installing Drupal, moving stuff round etc.?