Redirect 301 / http://new.example.com/

The only issue with this is that people might not notice that you've moved to a new domain, and thus might not update their links to you. As Matt Cutts confirmed a while back that 301 redirects do not pass full PageRank, and they seem to take a hell of a time to kick in these days, that's somewhat of an issue: we'd rather have people update their links.

The proper redirect

So we want to tell people that you've moved to a new domain, but only people who came through old links to your site. And we still want to keep that 301 redirect in place, to preserve as much of the value from the old site as we can.

So, what if we redirected to http://new.example.com/#moved? The search engines don't care about anything from the hash onwards, so the value of the redirect would still be maintained. We could then use javascript to detect the value of the hash tag, and display a notice to our visitors.

There's an issue with that as well though: with the redirect 301 / line above, we redirected everything after /, to new.example.com/, so for instance /test/ would be redirected to new.example.com/test/. If we added #moved to the end of that URL, we would end up with new.example.com/#moved/test/ and that wouldn't work. So we'll need to make a bit of a fancier redirect:

RedirectMatch 301 /(.*)? http://new.example.com/$1#moved

That should work. Notice though that when you have code in place adding a / to the end of your URL's if not existent, that code should conserve any hash tags in the URL.

Showing the domain move message

So now, let's move on to the javascript part to actually show people a "we've moved" message, which is actually pretty simple. You create a div with the message you want to show, and put it in your footer, something like this:

<div id="domainmovemsg" style="display:none;">
  We've moved from old.example.com to new.example.com, 
  please update your feeds & links!
</div>

As you can see, we default it to display: none; so not everybody sees it, and then you add this tiny snippet of javascript, also in the footer of your page, after you've loaded the div above:

if (document.location.hash == '#moved') {
  document.getElementById('domainmovemsg').style.display = 'block';
}

Example code

I've coded an example of this with some more styling etc., which you can find here. If you want to see it in action immediately, you'll have to click this link.

Change domain, and warn your visitors is a post from Joost de Valk's Yoast - Tweaking Websites.A good WordPress blog needs good hosting, you don't want your blog to be slow, or, even worse, down, do you? Check out my thoughts on WordPress hosting!

RewriteEngine On
RewriteCond %{HTTP_HOST} ^www.example.com$ [NC]
RewriteRule ^(.*)$ http://example.com/$1 [R=301,L]

Adding the www instead of removing it

And, as requested in the comments, the code to add www to your domain name:

RewriteEngine On
RewriteCond %{HTTP_HOST} ^example.com$
RewriteRule (.*) http://www.example.com$1 [R=301]

How to remove www from your URL with mod_rewrite is a post from Joost de Valk's Yoast - Tweaking Websites.A good WordPress blog needs good hosting, you don't want your blog to be slow, or, even worse, down, do you? Check out my thoughts on WordPress hosting!

Now I did, and I found the cacheAPC example to be very, very easy. It relies on the Alternative PHP Cache, an opcode cache PECL extension for PHP. I wrote two functions, which I then put in to all my pieces of code which I've published that use a lot of calls to the different API's. The first is curlopen, the function I use to open connections:

function curlopen($request) {
	$ch = curl_init();
	curl_setopt($ch, CURLOPT_URL, $request);
	curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);
	curl_setopt($ch, CURLOPT_TIMEOUT, 100);
	curl_setopt($ch, CURLOPT_FOLLOWLOCATION, true);
	$results = curl_exec ($ch);
	curl_close($ch);
	return $results;
}

The second one is the actual cache function, look at how easy it is:

function request_cache($url, $ttl) {
	if(!$doc = apc_fetch($url)) {
		$doc = curlopen($url);
		if ($doc === false) return false;
		apc_store($url,$doc, $ttl);
	}
	return $doc;
}

It basically does three things:

1. It looks if the requested resource is already in the cache, and if it is, it fetches that;
2. If it's not, it opens it through curlopen and stores it in the cache;
3. It returns the requested data;

As you can see the request_cache function takes two parameters: the request url and the TTL, which, in seconds, determines how long that resource should be cached. Now if you request a PageRank for a URL, it's fairly safe to set this to 24 hours, and you can see how much requests this saves!

PHP-APC: Speed up your web applications! is a post from Joost de Valk's Yoast - Tweaking Websites.A good WordPress blog needs good hosting, you don't want your blog to be slow, or, even worse, down, do you? Check out my thoughts on WordPress hosting!

PHP 301 for Apache:

header("HTTP/1.1 301 Moved Permanently");
header("Location: http://www.example.com/newpage/");
exit;

PHP 301 for IIS:

header("Status: 301 Moved Permanently");
header("Location: http://www.example.com/newpage/");
exit;

PHP 301 redirects for Apache and IIS is a post from Joost de Valk's Yoast - Tweaking Websites.A good WordPress blog needs good hosting, you don't want your blog to be slow, or, even worse, down, do you? Check out my thoughts on WordPress hosting!

A year or so back, I was using underscores in my URL's on this site for spaces, and I decided to switch them to dashes, since several people, including Matt Cutts, had blogged that this was "the way to go". Now at that time I just redirected all old URL's to new ones, which created like 30 lines in my Apache config, something I didn't really like...

This morning I took the time to find a more elegant solution, and the easiest one I could come up with is the following:

RewriteCond %{REQUEST_URI} ^(.*)_(.*)/$
RewriteRule (.*)_(.*)/ http://yoast.com$1-$2/ [R=301]

This will rewrite a single underscore to a single dash, using a 301 redirect. So if you have directories with four underscores, it will go through this rewrite four times before reaching the final URL. I had some directories in which this was the case, and made sure it only had to redirect a maximum of two times by adding the following lines above it:

RewriteCond %{REQUEST_URI} ^(.*)_(.*)_(.*)/$
RewriteRule (.*)_(.*)_(.*)/ http://yoast.com$1-$2-$3/ [R=301]

You could add even more lines like these if need be, I'd make sure that no more than two redirects are needed to rewrite the underscores into dashes.

The "/" on the end of the RewriteCond is there to make sure this is a directory, and not a file, since I've got quite a few images with underscores in the names and didn't want to bother renaming them.

Convert underscores to dashes with Apache mod_rewrite is a post from Joost de Valk's Yoast - Tweaking Websites.A good WordPress blog needs good hosting, you don't want your blog to be slow, or, even worse, down, do you? Check out my thoughts on WordPress hosting!

RewriteEngine On
RewriteCond %{REQUEST_URI} ^(.*)//$
RewriteRule . http://yoast.com%1/ [R=301]

Trailing double forward slashes in URL’s in the SERPs… is a post from Joost de Valk's Yoast - Tweaking Websites.A good WordPress blog needs good hosting, you don't want your blog to be slow, or, even worse, down, do you? Check out my thoughts on WordPress hosting!