Domain Masking: Don't do it

A very common scenario I see all the time working on small business, local SEO projects, is a situation where a client owns multiple domains, and they've "masked" those domains to their primary domain. I see this all the time, enough so that I thought it warrants a quick tip.

What is domain masking?

Domain masking is where you have one domain, let's call it domain1.com, and that domain is actually serving content from another domain, let's call that domain2.com (my domain naming creativity astounds you!).

So, with domain masking, if I type "http://domain1.com" into my browser's address bar, I get a page that appears to be identical to the page I get if I type "http://domain2.com" into my browser's address bar. Okay, so this is much more difficult to explain than I thought. Maybe it'll help if I explain what a redirect is, and how that's different from domain masking.

What's a redirect?

Let's say you set up a redirect from domain1.com to domain2.com. If you type "http://domain1.com" into your browser's address bar, you'll end up with the actual website located at domain2.com, but, and this is the really important part, the URL in your browser's address bar will actually change. In other words, when you type in domain1.com, the server responds and says, "hey dude, domain1.com has moved, it's new location is domain2.com." Your browser then says, "ok," and asks for domain2.com instead. You can see this in action if you type "http://www.wordpresshacker.com" into your browser's address bar. Watch what you just typed and you'll see it change to rlmseo.com and you'll end up on our homepage. That's because wordpresshacker.com is a domain we own and it's redirected to rlmseo.com.

This is different from domain masking in that with domain masking, if you type domain1.com, your browser won't ever get a message that says domain1.com has moved to (or is actually located at) domain2.com. Rather, the server says, "ok, I've got that page, here it is," and it gives you the content from domain2.com.

Why is domain masking bad?

If you've ever heard the word duplicate content, then you know why this might be bad. What happens when Google visits domain1.com and then visits domain2.com?

With a redirect, Google sends a request for domain1.com and the server tells Google that content has moved to domain2.com. The result is Google only finds the content on domain2.

With domain masking, Google sends a request for domain1.com and the server responds with the content from domain2.com, without telling Google the content has moved. Then, sometime down the line, Google might send a request for domain2.com and the server responds with the same content. The result is the exact same content is served from two completely separate URLs…in other words it's a major duplicate content problem.

Now, even though there's no such thing as a duplicate content penalty per se, there's the potential there for the search engines to get confused about which domain is the primary, and you could end up with all kinds of issues down the line.

So, avoid domain masking and instead, opt for a 301 redirect.