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Re: Pointing a domain to a domain

To: Kyle Wheeler <kyle-djbdns@memoryhole.net>
Subject: Re: Pointing a domain to a domain
From: Jonathan Duncan <jonathan@nacnud.com>
Date: Thu, 22 Mar 2007 13:51:15 -0600 (MDT)
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On Tue, 13 Mar 2007, Kyle Wheeler wrote:

On Tuesday, March 13 at 10:26 AM, quoth Jonathan Duncan:
However, I am wondering, is there a way to poing the domain name to another domain name like they requested? In case they change the IP of the domain so that it will always be correctly pointing to whatever IP ghs.google.com is using.

Use a CNAME.

As I have read, using the CNAME option is frowned upon.

CNAME is not so much frowned upon as it is frequently misused and/or misunderstood. CNAME is a *full* mapping, which means, for example, that if you have example.com set up as a CNAME for foo.com, then mail addressed to user@example.com will be delivered as if it had been addressed to user@foo.com (MX records for example.com will not be honored)---in some cases, mail servers actually rewrite the recipient address (whether they should or shouldn't is another matter). It also can have issues when you map a CNAME to another CNAME (imagine, for example, setting up an infinite chain of these---or a loop).

But, to do what you want to do, that's the only option. The only alternative is to set up a cron job to regularly look up the IP address and update your cdb.

For more information, read this: http://cr.yp.to/im/cname.html


Thank you all for your help. I am glad to learn that there are in fact valid reasons to use CNAME and that this was one of those cases.

Jonathan

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