example.com vs. www.example.com on different IP address

[doughayman]

Hi all,

I am asking the following question from a Google perspective:

- I have a domain that is almost 13 years old;

- All my internal references to pages are always in the
form of "www.example.com", not "example.com";

- All pages that are indexed in Google from this domain,
are all prefixed with "www.example.com";

- I have stipulated in Google (via WMT), that all references
to the example.com domain be displayed
as "www.example.com";

- I noticed that my ISP, whom I have been with for several
years has www.example.com and example.com map to 2
different IP addresses; specifically, the example.com
IP points to an old hosting server, and that maps to some
default page on that server, not the home page of my
www.example.com;

- I am using an old webserver (long story here) that does
not enable me to perform a 301 redirect from requests
that could potentially come in from example.com (to
www.exmaple.com). Similarly, there are no API rewrite
facilities with this webserver to accomplish this;

- My current ISP will permit me to change the example.com
IP address to be the same as my www.example.com IP
address, from a DNS perspective;

Given the above, would you recommend that I make the DNS change to equate these 2 domains to being the same IP address, or am I looking for trouble here ?

Thanks in advance.

[rainborick]

Google is rarely concerned with IP addresses, so in and of itself, the difference in IP addresses in your situation aren't a problem. The real question is what does the server return for requests to example.com? If it mirrors the www.example.com site, then this would be a reasonable situation to use the new rel="canonical" tag. If it doesn't mirror the www., then I would suggest using a <meta> refresh set to 0, on a page that simply informs users that the page has moved to the www. version, and includes a simple HTML link. For the past 4 or 5 years, the search engines have treated such <meta> refresh tags like a 301 redirect.

By the same token, I think the chances of a canonicalization problem arising on such a well-established domain are very, very small - even if you hadn't made a setting in the Webmaster Tools console. But given how limited you are in being able to manage your site at the present, I think you should give some serious thought to changing hosting services.

[doughayman]

Thank you for your suggestions, rainborick. They sound like viable solutions.

What are your thoughts, however, by me just fixing the DNS problems....that is, equating both example.com and www.example.com to being the same IP. Do you think this runs the risk of introducing canonicalization problems at all:

For example, will Google think that example.com/index.htm and www.example.com/index.htm are 2 different files with identical content (given the above) ?

Thanks again !

[rainborick]

If the only difference adjusting the DNS settings would be to use the same IP address, then it doesn't matter. Google is certainly used to seeing multiple IP addresses used across a single domain name. While I believe its pretty unusual for the root domain and the www. subdomain to reside on different IP addresses, I know it's not uncommon in general. If you want to do it in order to be absolutely sure, go ahead. It can't hurt.

But from there, it would be a good idea to either use the rel="canonical" or the <meta> refresh. I'd lean toward the rel="canonical" because it has more official blessing from the search engines. Google barely acknowledges their support of the <meta> refresh, but they make it clear that it should be a last resort when server redirects aren't possible.