Page Redirects
When you rename a page or move a page or site from one directory location to another, this results in a change in URL for that page or site. Without a redirect page, users following links to the old URL will get a 404 (Page not found) error. Since you may have users who have bookmarked specific pages on your site or there may be other web sites linking to your pages, its a good idea to set up a redirect so that visitors will automatically route to the new location, as invisibly as you desire. You can either do this using the meta-refresh approach or with Apache's mod_alias module.
Meta-refresh
In the META-HTTP-EQUIV tag, the content attribute indicates how many seconds (in the example below, 5 seconds) before the user is whisked off to the new location specified in the URL attribute. We recommend using 3-5 seconds on all redirects so the users are made aware that the page has moved and have time to read the short message displayed. Zero second redirects are not recommended if you want your users to update their bookmarks.
You may copy this code to create a new page at the old location, editing appropriately:
<!doctype html public"-//w3c//dtd html 4.01 Transitional//EN">
<html>
<head>
<meta http-equiv="Refresh" content="5;
url=http://www.newlocation.com/page.html">
<title>Please note the change of address!</title>
</head>
<body bgcolor="#ffffff">
<h2>We have moved! Please update your bookmarks! If you are
not automatically redirected to the new address in 5 seconds,
please go to <a href="http://www.newlocation.com/page.html">
http://www.newlocation.com/page.html</a></h2>
</body>
</html>
mod_alias
The Apache module mod_alias allows you to provide intelligent, seemless, and nearly instantaneous redirection for pages that have moved. The way in which it redirects your end-users may be of less concern to you than the way in which it redirects search engines. By providing the appropriate HTTP response codes, using mod_alias vs. the meta-refresh approach will improve your search engine listings (internally and externally).
By customizing your .htaccess.mit file (in this case usually one at the root of your web site, in the same directory as your home pages) you can indicate whether certain content has moved temporarily, permanently or has been removed altogether.
Redirecting a single page:
Redirect permanent /one http://example.com/two
Redirect 301 /one http://example.com/two
Redirect temp /one http://example.com/two
Redirect 302 /one http://example.com/two
Redirect gone /one http://example.com/two
Redirect 410 /one http://example.com/two
Redirect seeother /one http://example.com/two
Redirect 303 /one http://example.com/two
Redirecting many pages:
You can redirect many pages using pattern matching
RedirectMatch 301 /ist/web/(.*)$ http://web.mit.edu/wcs/$1
When used on Athena, the line above will permanently redirect requests for any content in the web subdirectory of the ist locker to corresponding URLs in the wcs locker. (e.g. /web/reference/index.html will be permanently redirected to http://web.mit.edu/wcs/reference/index.html)
For more information: see the Apache Group's documentation on mod_alias
