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I purchased a dedicated static IP address from my hosting company to host my domain name. The IP will point to me domain when I ping it. However, when I conduct reverse DNS lookup, my dedicated IP points to somewhere else - other domain.

when I check with the tech support, they said that they are not able to change that because the domain belongs their data center.

Are they telling me the truth? As my understanding, the dedicated static IP should belong to my domain only. Please help! Thank you.

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  • Perhaps you should post the IP and the domain name it should be pointing to so others can look at the public records? Nov 16, 2010 at 17:26

2 Answers 2

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The A record (www.yoursite.com or mail.yoursite.com) will be controlled by you - you'll have your registrar (GoDaddy?) point to Name Servers that you control. That works for the forward lookups.

The reverse lookups (PTR) records don't belong to you. That address belongs to the ISP. As such, when someone goes looking for what that address resolves to, it's going to resolve to a name of their choosing. You have a small chance of getting them to change it, but I would not hold your breath.

They need to keep things organized on their side as well... Think about it like this, from their perspective...

66.3.3.3 66-3-3-3-isp.com
66.3.3.4 66-3-3-4-isp.com
66.3.3.5 yoursite.yourdomain.com
66.3.3.6 66-3-3-6-isp.com

Now if you leave, it's even more work for them to change it back... Like I said, don't hold your breath. :)

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  • This is a good explanation. However, don't hesitate to contact your ISP about it, especially if you have bought some sort of "business" package. A valid PTR record is encouraged if you are going to run your own mail server, so ISPs commonly will handle this for their business customers.
    – mhud
    Nov 16, 2010 at 18:32
  • I am planning to run my own hosting company selling reseller hosting plans. So, I think this is very important to me. However, my hosting company has refused to make any change for me.
    – need-help
    Nov 16, 2010 at 21:31
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There are two concepts - forward and reverse DNS lookup. Forward lookups are lookups that resolve domain names to IP addresses. If you do:

nslookup your-domain-name.com

you should get your IP. This is what you can control as you own your domain. Each domain is found by looking from top level domains downwards toward your domain name. I.e. in case of abc.def.example.com, you would start by asking the DNS server responsible for com, then continue downwards asking the DNS server responsible for com.example and so on until you reach the DNS that can resolve abc.def.example.com itself (which may be the DNS server for example.com by the way, depending on the setup of subdomains).

Reverse lookups are different. They map IPs to domain names by following a different route. They do not follow the domains, but IP address allocations. That is, this is the responsibility internet provider responsible for the block of IPs to which your IP belongs to. You don't have the control over that, this needs to be resolved by the entity who controls the IP address itself.

If you change your internet provider, you will change your IP and you can change your domain to point to that IP easily. However, you will need to contact you internet provider to update the reverse lookup.

Take a look here for a more info:

Hope this helps.

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  • @need-help You are welcome, glad I could help! Nov 16, 2010 at 18:05

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