Often times you will need to shutdown a website for updating bug fixes, testing a new theme, and other common reasons. But the process on WordPress can be a hassle since you would need to redirect all the traffic onto a new default page. This can easily be handled using some open source plugins from the WP repository.
I want to present a small collection of WordPress plugins for handling downtime on your website. Each of these is open source and easy to install on any website. You can generally activate settings and themes from the backend admin panel. Using a pre-built method will save a lot of time so that you can focus on fixing the site or adjusting your changes to get back online.