Need to redirect the homepage to a different url but keep the site live and accessible
They are many solution to redirect from the page.


If you are using Apache you can use .htaccess to redirect the front page to a different website. This would be the faster due that is on the server level. Here is more information about redirects on Apache.
If you are using Nginix here are some instructions 
Another option would be doing it on the theme level. If have access to the theme you can write  sites/all/themes/YOURTHEME/page.tpl.php.

&lt;?php
   if(drupal_is_front_page()) {
     header("location: http://www.RedirectPage.com");
     exit;
   }
?&gt;

If you dont have access to the theme or to the server. The easiest way to have a redirect is by using the meta tag. You can add a block to the front page and add the following code.

     &lt;meta http-equiv="refresh" content="10; url=http://www.RedirectPage.com/"&gt;



For more information about Redirect check this article.