I run our research group website, but don't have direct access to the university DNS server. However, we have two addresses pointing at the same IP - one is the old website and the canonical name is the current one.

Old name: lima.wustl.edu
Name name: pappulab.wustl.edu

The issue is that any google search returns ONLY the old name (lima.wustl.edu) despite the fact that lima.wust.edu is an alias and pappulab.wustl.edu is the canonical name.

Is there anything I can do to make the webcrawlers use the pappulab.wustl.edu address instead of the lima address? We could just kill lima, but this would break lots of links in various placed.

Some relevant lookups

Address: name = pappulab.wustl.edu.

nslookup lima.wustl.edu

lima.wustl.edu  canonical name = pappulab.wustl.edu.
Name:   pappulab.wustl.edu

2 Answers 2


Well, I am not too sure adjusting DNS entries is the best way to handle this. Or would even solve the issue. You do not have an IP address issue, but rather a content indexing & hostname change issue.

I would instead recommend using Apache rewrite rules—via mod_rewrite—to do this on lima.wustl.edu instead. This is—of course—assuming that you are running the server on Apache. If not, someone else should chime in with your server’s specifics. So here it is:

RewriteEngine on
RewriteRule ^(.*)$ pappulab.wustl.edu$1 [NC,L,R=301]

What this will basically do—when set for the Apache config of lima.wustl.edu—is take any URL connected to lima.wustl.edu and send it straight to pappulab.wustl.edu but with a 301: Moved Permanently header status.

So a URL like this:


Would be sent to:


Links will not break. And the process is pretty seamless to a casual web browser. Meaning no interruption in access that is perceptible to a human. And because the 301 header status is sent, crawlers will take note & update links eventually. That is always based on the crawler schedule & logic. But I would say in a few weeks or months all of the URLs will properly be reindexed to go to pappulab.wustl.edu. To play it safe, leave this redirect up for at least a year.


You could use a robots.txt file to inform Google not to crawl the old domain. If the old domain still has a DNS entry and is active, place the following code into your robots.txt file:

User-agent: *
Disallow: /

If you need the old URLS removed quickly then you can do this in Webmaster Tools.

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