Site in maintenance. How to redirect visitors?

Question

My PHP site in maintenance. How to redirect visitors to a "site in maintenance" single page?

I heard something about app_offline.htm for ASP.NET.

Is there something similar for PHP?

• I want that every page from "mysite.com" be redirected to "maintenance.php";
• I don't want to do the minimum modification in the existing site pages, ideally no one.

Apache version 2.2.15 under Linux
PHP version 5.2.13

Answer 1

You really don't give enough details (server, framework, etc). If you are on Apache, add to your .htaccess:

# prevent infinite redirect loops
RewriteCond %{REQUEST_URI} !^/back-soon-updating.php$
# not on development server
RewriteCond %{HTTP_HOST} .com$
# let admins enter to verify the update has worked
RewriteCond %{QUERY_STRING} !c=u
RewriteRule .* back-soon-updating.php [L,R=307]

Answer 2

The PHP way : Create an maintainance.php and add this in your index.php:

$offline = true; // <== change this to false when you go online again.

if($offline){
  header("Location: maintainance.php");  // <== redirects all to maintainance.php
  exit;
}

Answer 3

There is no "Global way", either you have to configure your webserver, to go to a specific site, or if you include a page everywhere, add

header("Location: offline.php");
die();

To redirect your users temporary.

Answer 4

You should set proper header in response as well (HTTP Response Code 503). There are Apache only ways of doing it using mod_rewrite and mod_headers

However for a simple solution without the need of mod_headers, follow the steps below

• Use your apache conf / .htaccess as mentioned by Coronatus to redirect all users except developers to a PHP maintenance script. Make sure the redirect is indeed temporary (using a 307 redirect code as mentioned by Zach)
• In your PHP script, set the response header to following at very begining of the script.

header('HTTP/1.1 503 Service Temporarily Unavailable') //send the proper response code

header('Retry-After: 3600') //Retry after an hour

This should get you what you want.

Answer 5

As my Apache in under Linux I do the following:

Created ".htaccess" file under the site root with the folowing content:

Options +FollowSymlinks
RewriteEngine on

RewriteCond %{REQUEST_URI} !/images/mainetnance.png$
RewriteCond %{REQUEST_URI} !/maintenance.php$

# here filter the developer's IP/
#RewriteCond %{REMOTE_HOST} !^888\.888\.888\.888

RewriteRule $ /maintenance.php [R=302,L]

Is to remark that I added to filter the .png files, cause I use an image (/images/mainetnance.png) for the maintenance.php, and this image should remain visible, because of global redirect.