DNS i.e., the Domain Name Server also known as Domain Name System is the hierarchical and decentralized system of identifying systems reachable through the Internet Protocol networks.
It works by looking up your website by finding its domain name and then locating its associated IP address. Whereas, the reverse DNS first looks up for an IP address and then locates the associated domain name.
The reverse DNS is actually a process that involves the conversion of an IP address back into a domain name. While the traditional DNS translates domain names (like – example.com) into IP addresses (like 126.96.36.199), reverse DNS does the opposite – it translates IP addresses into domain names.
The Reverse DNS is mainly used for:
- Email Servers: Reverse DNS is commonly used by email servers to verify the legitimacy of incoming emails. Many email servers check if the reverse DNS entry of the IP address sending the email matches the domain from which the email claims to be sent. This helps in preventing spam and identifying potential sources of malicious or fraudulent emails.
- Network Troubleshooting: Network administrators use reverse DNS to understand the domain names associated with specific IP addresses. This can aid in troubleshooting network issues, identifying the source of network problems, or verifying the ownership of particular IP addresses.
- Security: Reverse DNS can provide additional information about the server sending traffic to your network. It’s used in security measures to analyze and filter incoming traffic based on the domain names associated with the IP addresses. This can be helpful in identifying and blocking potentially harmful or unauthorized access attempts.
- Logging and Analytics: Some systems and applications use reverse DNS to log the domain names of incoming connections, providing more meaningful information in logs and analytics.
- Online Reputation: Some online services use reverse DNS as a factor in determining the reputation of an IP address. A well-configured reverse DNS entry can contribute positively to an IP address’s reputation, while a lack of reverse DNS or misconfigured entries might affect it negatively.
Setting up reverse DNS involves creating a PTR (Pointer) record in the DNS zone files, and linking an IP address to a domain name. This PTR record helps establish a connection between the IP address and the domain name it represents.
It’s important to note that the accuracy and presence of reverse DNS entries can vary. Some organizations maintain proper reverse DNS entries for their IP addresses, while others might not. Additionally, the process of setting up and managing reverse DNS might involve coordination with the hosting provider or internet service provider.
But at Sangkrit.net you don’t have to worry about that, you can easily setup the reverse DNS by following a few easy steps, and the round-the-clock online support is also available to help you in case you feel stuck anywhere.
How To Setup Reverse DNS?
At Sangkrit.net, you can easily set up a reverse DNS (RDNS) lookup for your Dedicated Server. To start, simply login to your Sangkrit.net account and follow these steps:
- Visit your My Products page
- Click Servers
- Next to your server, click Manage
- Enter the domain name you want to be associated with the server IP address, in the DNS record field
- Now click Update
The system will start an automated process of completing the reverse DNS setup. This can take up to 48 hours for the changes to propagate to your server.
If you have multiple IP addresses on your server, repeat the process for each IP address you want to set up Reverse DNS for.
Now the traditional process of setting up reverse DNS is a little bit different, you may follow that also:
- Log in to WHM: Access your WHM control panel using your administrator credentials.
- Navigate to “DNS Functions”: In WHM, search for or locate the “DNS Functions” section. This is where you’ll manage DNS-related settings.
- Edit DNS Zone: Under “DNS Functions,” click on “Edit DNS Zone.” This will allow you to modify the DNS zone files for the domain.
- Select IP Address: Choose the IP address for which you want to set up Reverse DNS (PTR record). Click “Edit.”
- Add PTR Record: In the DNS zone editor, you’ll see the existing DNS records. To add a PTR record, scroll down to the “Add New Entries Below this Line” section.
- Enter PTR Record Details: Fill in the following information to create the PTR record: Name: Enter the last segment of the IP address in reverse, followed by “in-addr.arpa.” For example, if the IP is 192.0.2.1, the name would be “188.8.131.52.in-addr.arpa.” TTL: Set the Time to Live for the record.
- Save Changes: Once you’ve entered the PTR record details, click the “Save” or “Save Zone File” button to save the changes.
- Update DNS Zone: After saving the changes, WHM will update the DNS zone file with the new PTR record.
- Verify PTR Record: You can verify the PTR record by using the “dig” command in the terminal or through online DNS lookup tools. It might take some time for the DNS changes to propagate across the internet.
You should also know that, when you run your own email server, and configure DNS to point to your domain name, there are some servers that are going to reject emails from IP addresses when not having an rDNS. The reverse DNS also helps when you need to troubleshoot your network while running a traceroute etc.
Reverse DNS is a useful mechanism that adds an extra layer of information and security to online communication and networking processes.