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I have setup a Centos 5.5 server and a domain name (say pointing to it (using bind9) with custom nameservers (like and Everything works fine but there is something more I would like to have and don't know if it is possible.

Is it possible to have the returned host to be (PHP gethostbyaddr()), not And how do I implement it if it's possible?

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up vote 2 down vote accepted

You need ownership to reverse that IP or IP block. Chances are if this is a home provider they will not allow that to happen.

If you are at a datacenter they might give you the rights or you will have to let them know what you want it reversed to and they will do it for you.

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They will do it for you / Or you through an API unless you have one more more C networks (256 addresses these days, /24). Reverse mapping assignment in DNS always works in /24, so smaller networks can not be delegated. – TomTom Jan 4 '11 at 13:12
@TomTom outlines a method for delegating blocks smaller than /24. – BillThor Jan 4 '11 at 17:23

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