The Linux and Unix Menagerie: Simple Site Redirection On Apache For Linux Or Unix

Hey there,

Today we're going to look at simple ways you can do site redirection using a few basic methods for Apache on Linux or Unix. I'd presume that the functionality works exactly the same for Apache on Windows, but that would (to misquote a cliche) make a "pres" out of "u" and "me" - yeah, the "assume" version of that plays much nicer ;) Tomorrow, we're going to follow up with more advanced ways to do site and subdomain redirects using "mod rewrite".

Site redirection, in and of itself, is fairly easy to do with just straight-up HTML or PHP, but it has its limitations. For instance, if you wanted everyone who visited www.myxyz.com to be redirected to www.myotherxyz.com, all you'd have to do would be to add some simple code to your index.htm(l) or index.php file. In HTML, you could just add this line in the <head> section:

<meta http-equiv="refresh" content="30;url=http://myotherxyz.com/">

This would allow for thirty seconds to pass before the redirect was called. You might want to make that shorter or longer, depending upon how much interactivity you wanted your visitor to have before being redirected. You may want to allow them to use the old site if they want and redirect them if they don't click on a link in 30 seconds, or something like that. If you really want them to not have any choice, try setting the time (content) to 0. Although this, technically, redirects immediately, depending on someone's connection, the server hosting the website, etc, slow page load could cause the user to see the original page before it refreshes to the new site. If you're only using a page for this purpose, you should leave the body blank or with just a similar background image as your new site.

PHP is a bit faster, although still subject to the limitations of the interacting components that affect the HTML redirect (although not to the same degree). In PHP, you could do the same thing with this little chunk of code:

<?
Header( "HTTP/1.1 301 Moved Permanently" );
Header( "Location: http://www.myotherxyz.com/" );
?>

The most efficient method (of the three we're going run through here today) is to use htaccess. This point will be expanded upon to a good degree in tomorrow's post, since the combination of htaccess and "mod rewrite" can allow you to do a lot more than just standard redirection. Using htaccess, you could create a file called, strangely enough, .htaccess in your site's main directory (or root or home directory, or base directory or whatever you prefer to call it) that contained the same directions as above, although with yet another syntax. A simple 301 site redirect in .htaccess can be written this simply (the entire file from top to bottom):

redirect 301 / http://www.myotherxyz.com/

It just doesn't get any simpler than that :) For the htaccess method, since there are no double quotes surrounding your arguments (old-site-name new-site-name) you need to double quote any addresses that include spaces. Simple enough:

redirect 301 "/my old index.html" http://myotherxyz.com/

And that's all there is to it! For a little bit of trivia, you may have noted that we ended all of our redirect destinations with a closing / ( www.myotherxyz.com/ as opposed to www.myotherxyz.com ). The reason we do this is actually still standard protocol. You can actually do the test yourself right now to prove it out. When you send a standard web server a URI request for, say, http://www.google.com (for instance), that actually generates a 301 site redirect and plops you at http://www.google.com/, which is the properly formatted address. It happens very quickly and, of course, only counts when you're requesting a directory. If you specify a file, like http://www.google.com/index.html, you'll either get the page you were expecting or some other error (perhaps even a 301), although it should be noted that some web servers don't do this anymore in all instances (http://www.google.com/news, for example). Still, being a dinosaur, I prefer to stick to the way that should always work.

Give it a shot. It might be more fun than pick-up-sticks ;) If you find a site that does it, you can see the redirect in action using simple Telnet. Take this example using http://abc.go.com/daytime (Although this page actually does a 302 redirect - for temporary redirection - right now and takes you to a specific index page) - I grew tired of trying to find sites that use 301 redirection on sub-directories and you can't telnet to any server and not request a page, unless you want that 404 ("GET /" works, but proving the redirect by doing "GET " doesn't ;)

$ telnet abc.go.com 80
Trying 198.105.194.116...
Connected to abc.go.com.
Escape character is '^]'.
GET /daytime HTTP/1.0

HTTP/1.1 302 Found
Connection: close
Date: Thu, 26 Feb 2009 00:19:27 GMT
Location: /daytime/index?pn=index
Server: Microsoft-IIS/6.0
P3P: CP="CAO DSP COR CURa ADMa DEVa TAIa PSAa PSDa IVAi IVDi CONi
 OUR SAMo OTRo BUS PHY ONL UNI PUR COM NAV INT DEM CNT STA PRE"
From: abc07
Set-Cookie: SWID=54AE3DC5-FB42-4F6C-8B10-82E506FFD442; path=/;
 expires=Thu, 26-Feb-2029 00:19:27 GMT; domain=.go.com;
Content-Length: 163
X-UA-Compatible: IE=EmulateIE7

<HTML><HEAD><TITLE>Moved Temporarily</TITLE></HEAD><BODY>This document
 has moved to <A HREF="/daytime/index?pn=index
">/daytime/index?pn=index
</A>.<BODY></HTML>Connection closed by foreign host.