ServerBuddies Support Blog

Naming the IPv4 reverse DNS zone

To properly format the Domain field in the interface using IPv4:

1. Drop the last octet from the IP address.
2. Reverse the order of the remaining octets.
3. Append in-addr.arpa to the end of the remaining octets.
4. Enter this value in the Domain field of the Add a DNS Zone feature.

For example, the reverse DNS zone for 192.168.0.1 is 0.168.192.in-addr.arpa.

You will specify the last octet of the IP address within the zone file.

What is Reverse Domain Name Hijacking?

Reverse domain name hijacking has become a significant security threat that is largely overlooked by the web hosting community. This form of domain theft involves copyright owners asserting expansive trademark rights in order to take ownership of a domain from its rightful owner. In most cases, this form of domain theft is actually practiced by larger companies that want to claim a domain name from a smaller company.

In the case of ‘reverse domain name hijacking’ the offending party will typically file a report in conjunction with the UDRP (Uniform Domain-Name Dispute-Resolution Policy), which claims that the current domain owner registered the domain in violation of trademark rights. The goal in filing this report is to have the current domain ownership rights revoked and handed over to the offender. Unfortunately, even though in many cases the larger companies are overstepping their trademark rights, most small companies do not have the funds or knowledge needed to defend themselves through any type of opposition. it is possible to file an action in court against the offending party, which states that your registration of the domain was lawful and in accordance with the Anticybersquatting Consumer Protection Act (ACPA). The ACPA is basically a law that serves to protect domain registrants from the outreaching and unjust claims of trademark owners.

Configuring Reverse DNS in WHM

Reverse DNS uses pointer records (PTR) to convert IP addresses into domain names. This is the opposite of forward DNS, which uses A records to convert domain names into IP addresses.

First, add a new DNS zone file. You can accomplish this using the Add a DNS Zone feature in the DNS Functions section of your WHM interface (Main >> DNS Functions >> Add a DNS Zone).

To continue, enter the IP address and proper reverse DNS zone name in the appropriate fields.

To properly format the Domain field in the interface.

Take the first 3 octets of the IP address, Reverse them, and Affix in-addr.arpa to the end. So, for example, the reverse DNS entry for 192.168.0.1 is 0.168.192.in-addr.arpa. After you have filled out these 2 fields, click the Add Zone button.

One you have created your zone file, you can edit it. You can do this using the WHM Edit DNS Zone screen (Main >> DNS Functions >> Edit DNS Zone). Your zone file should already contain an NS entry for every authoritative nameserver associated with your server. To finish this process, we need to add a PTR record for each IP address we wish to name in the last octet of 192.168.0.

After the reverse DNS zone has propagated, run a test to ensure that you have properly configured reverse DNS. To do so, you can use the following command:

If you have properly configured your reverse DNS zone file, the output should resemble the following:

Adding reverse IP Lookup in DirectAdmin

Any modern verion of DA will be able to do this through the interface.

Go to: Admin Level -> DNS Administration

Scroll to the bottom to the “Add Zone” section.

Enter your information normally:

where server.hostname.com is the hostname of your server. The IP is your server IP (license IP)
and ns1/ns2 can be any NS your server uses.

Click the “Create Reverse IP Lookup” checkbox, then click “Add”.

Reference link: http://directadmin.com