Problem with Reversed DNS on Webmin

Steve Hill
Steve Hill used Ask the Experts™
on
Hello,

I created Reversed DNS for my domains.

The main domain is domain1.com with Name server ns1.domain1.com and ns2.domain1.com

I configure some subdomains from: mail01.domain1 to mail10.domain1.com.

Then I add the new virtual Machine, with domain name: domain1.com.

I create the subdomains again from mail01.domain2.com to mail10.domain2.com with reversed ip.

I have each ip for each sub domains.

By the way, when dig the subdomains of the domain1.com, they are all resolved to first domain.

$ dig -x xxx.xx.xx.xx +short
mail01.domain2.com.

(xxx.xx.xx.xx is the ip reversed for mail01.domain1.com)

I really don't understand why. I tried to delete all and created again but still the same result.


Here is my situation.
http://ubuntuforums.org/showthread.php?t=2298300
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Daniel McAllisterPresident, IT4SOHO, LLC

Commented:
Reverse DNS (or PTR) records in DNS are not served by DOMAIN NAME nameservers, and for "the Internet" the PTR record for your WAN IP address(es) is/are controlled by your ISP.

While it is possible for an ISP to "delegate" the PTR (in_addr.arpa) resolution to you, that is HIGHLY unlikely unless you have a reasonably large subnet.

This is a common question people ask... but if you think about it, when you resolve a NAME to an IP address, you start at the ROOT and work your way down the domain NAMES listed. So when you try to resolve a NUMBER (IP address), why (or more correctly, HOW?) could you eventually get to a domain1.com nameserver?

I hope this helps, tho a "you can't do that yourself" isn't usually a popular answer.

Dan
IT4SOHO

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