URL Redirection

The configuration directives discussed in the above sections tell Apache to get content from a specific place in the filesystem and return it to the client. Sometimes, it is desirable instead to inform the client that the requested content is located at a different URL, and instruct the client to make a new request with the new URL. This is called redirection and is implemented by the Redirect directive. For example, if the contents of the directory /foo/ under the DocumentRoot are moved to the new directory /bar/, you can instruct clients to request the content at the new location as follows:

create .htaccess file and insert this line
   

Redirect permanent /foo/ http://www.example.com/bar/ 

This will redirect any URL-Path starting in /foo/ to the same URL path on the www.example.com server with /bar/ substituted for /foo/. You can redirect clients to any server, not only the origin server.

Apache also provides a RedirectMatch directive for more complicated rewriting problems. For example, to redirect requests for the site home page to a different site, but leave all other requests alone, use the following configuration:

   

RedirectMatch permanent ^/$ http://www.example.com/startpage.html 

Alternatively, to temporarily redirect all pages on one site to a particular page on another site, use the following:

   

RedirectMatch temp .* http://othersite.example.com/startpage.html 

 

If wanting to use Apaches Mod_Rewrite (Module MUST be loaded to the server)

in .htaccess

Options +FollowSymlinks
RewriteEngine on
RewriteRule ^index\.html$ YaBB.pl
 

or

Options +FollowSymlinks
RewriteEngine on
RewriteRule ^index\.html$ http://www.yourdomain/cgi-bin/yabb2/YaBB.pl
 

* Although highly unlikely, your host may have +FollowSymLinks enabled at the root level, yet disallow its addition in .htaccess; in which case, adding +FollowSymLinks will break your setup (probably a 500 error), so just remove it, and your rules should work fine.

Though this is the simplest example possible, it may throw a few people off. The structure of the ‘old’ URL is the only difficult part in this RewriteRule. There are three special characters in there.

   * The caret, ^, signifies the start of an URL, under the current directory. This directory is whatever directory the .htaccess file is in. You’ll start almost all matches with a caret.
   * The dollar sign, $, signifies the end of the string to be matched. You should add this in to stop your rules matching the first part of longer URLs.
   * The period or dot before the file extension is a special character in regular expressions, and would mean something special if we didn’t escape it with the backslash, which tells Apache to treat it as a normal character.

So, this rule will make your server transparently redirect from Index.html to the YaBB.pl page. Your reader will have no idea that it happened, and it’s pretty much instantaneous.

Forcing New Requests

Sometimes you do want your readers to know a redirect has occurred, and can do this by forcing a new HTTP request for the new page. This will make the browser load up the new page as if it was the page originally requested, and the location bar will change to show the URL of the new page. All you need to do is turn on the [R] flag, the NC is non case sensitive by appending it to the rule:

RewriteRule ^old\.html$ new.html [R, NC]  

   e.g. (.+)\.html? matches foo.htm and foo.html
        (foo)?bar\.html matches bar.html and foobar.html

further info here: Rewrite Rule Tutorial