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I'm coding an application the lets people attach their custom domains to it without my manual intervention or messing with httpd.conf.

So I need a method very similar to the method described by Google at the following URL: Except I'm not Google, so I may switch hosting provider anytime and the IPs will be completely changed.

That will cause a HUGE problem since it means I have to get everyone to update their domain CNAME settings which is impossible without severe downtime.

So how can I have the domains pointed to something fixed like ns1/

Your help would be greatly appreciated.

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up vote 2 down vote accepted

A CNAME record is just a pointer to another record. So you setup your own record, like; then tell your customers to point their CNAME at it. Tell them not to use A records because it will break eventually.

Also, when your changing IPs, know that it may take a long time for DNS to update properly. You should plan on at least 1 whole week; though a more conservative number would be 1 month.

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Why Google uses IP addresses then instead of – emurad Mar 15 '11 at 13:59
Google owns those IPs. They get to decide exactly how they're used. You don't own any IPS, at best you can lease some, but the owner can still yank them anytime they want. – Chris S Mar 15 '11 at 15:37
Thanks it worked. One last question, why Google asks to create 4 CNAME records instead of only one? – emurad Mar 16 '11 at 8:28
They ask you to create 4 for DNS RR load balancing. It's not a very effective form of load balancing on it's own, but I strongly suspect that Google is doing something unique on the back end. – Chris S Mar 16 '11 at 12:27

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