ClouDNS

Featuring in our list is the freshly launched ClouDNS DNS tool. This tool is intended for examining DNS records linked to a specific host alongside measuring the velocity of DNS queries. Some of the records that it will show information are A, CNAME, PTR (responsible for Reverse DNS lookup), MX, CAA, NS (needed to create DNSSEC), etc. It also incorporates a comprehensive audit feature. Developed by ClouDNS, the functionality of the tool has been designed considering the need of users to optimize their server’s performance effectively. The tool offers three types of assessments – DNS records, DNS audit, and DNS speed assessments, providing a holistic insight into the server’s DNS operation. The best part? It’s completely FREE!

DNS.Computer

DNS.Computer is highly efficient and simple to use. With just the insertion of the domain name and a click on ‘audit’, this tool generates a detailed report featuring observations and suggestions for optimization. This report, even available as a download in PDF format, provides valuable insights such as nameservers at the parent server, synchronization of NS records, and data contained in the SOA (Start of Authority) record.

It also showcases A record data by location with their response times, giving you insightful geographical distribution of your DNS. Plus, it displays an average response time for your DNS, advising a switch to Anycast DNS if the response time is significantly high. Overall, DNS.Computer is a dynamic tool that offers quick and specific insights to boost your DNS performance.

30-day Free Trial for Premium Anycast DNS hosting

Pingdom DNS Test

Pingdom DNS Test outshines its dual-feature of web page speed testing and DNS troubleshooting. It pinpoints performance bottlenecks, providing insights to optimize your site’s speed and user experience. Advanced diagnostics are visualized using color codes, icons, and dots, making it a hassle-free tool for improving site performance.

Additionally, the DNS tool provides intuitive visual aids, using color codes to denote different stages of a request, icons for various content types, and colored dots for different HTTP response codes. 

What is Web (HTTP/HTTPS) monitoring?

Into DNS

IntoDNS takes DNS evaluation to a new level by providing a detailed assessment of your server’s health and configuration status. It generates exhaustive DNS reports with actionable recommendations for improvements, backed by references to official protocol documentation. This covers a series of checks from MX records to SOA data and even WWW IPs, making it a powerful tool for enhancing server performance and stability.

Check Host

Check Host DNS tool provides substantial insight into any website’s domain. By entering a hostname or IP address, it can provide data from nameservers located in different countries concurrently. This quick global overview can provide you with pertinent information about your domain from various locations. 

After you input a domain into the Check Host DNS tool, it will give you comprehensive information, including the DNS result under specific categories such as ‘Location,’ ‘Result,’ and ‘TTL (Time to Live).’ Each of these categories gives you insight into different aspects of your domain’s DNS performance in various locations worldwide. That means, you can evaluate the response time (ping) from a variety of locations, which aids in testing server speed globally.

What Ping monitoring is?

View DNS

ViewDNS offers an all-embracing analysis of your domain’s DNS settings. Aimed at assisting webmasters and system administrators, this tool completes multiple tests to uncover DNS-related issues. Moreover, it checks A records for each NS at parent servers and whether the local nameservers send the IP address (glue) along with your NS records. These results are displayed in a readily understood format, offering valuable insights for your DNS health and improvement recommendations.

Suggested article: What are Glue records?

WhatsmyDNS

WhatsmyDNS effectively simplifies DNS queries with its DNS Lookup tool. It allows you to query DNS servers and receive quick insights for any domain name. The tool is designed to support most common DNS record types and also lets you choose from a selection of DNS servers. It’s a valuable resource for conducting a fast and robust DNS check.

DNSdumpster

DNSdumpster also deserves a mention – this is a no-cost domain research tool that’s instrumental in identifying specific hosts associated with a particular domain. Conducting a visibility check of hosts from the perspective of potential attackers forms a crucial aspect of a security assessment process, and this is exactly what DNSdumpster assists with. It also features an additional unique functionality called ‘mapping the domain,’ the data for which can be conveniently downloaded in a .xlsx format for a comprehensive list of hosts. This tool is particularly useful for those focusing on enhancing their server security measures.

Benefits of regular DNS audits

Performing regular DNS audits is essential to maintaining the health of your server and website. These audits can identify issues such as outdated or incorrect DNS records, misconfigurations, and potential security vulnerabilities. By regularly checking the accuracy and performance of your DNS setup, you ensure your domain resolves correctly for all users, reducing the chances of downtime or delays. DNS audits also help you stay compliant with best practices, optimize load balancing, and improve your website’s speed by using the best available resources. Ultimately, consistent DNS audits lead to enhanced performance, increased security, and a better user experience.

Conclusion

In summary, these DNS tools offer a range of features to help you test and optimize your server’s DNS performance, ensuring global accessibility, troubleshooting, and security enhancement. Whether you’re a novice or an experienced user, these tools provide valuable insights into your DNS infrastructure’s health and performance

The post 8 DNS tools for testing your servers appeared first on ClouDNS Blog.

What is rDNS?

You probably already know what a forward DNS is. It links the associated hostname/domain to the IP address. Now think from the opposite direction. rDNS, also known as Reverse DNS, is doing the mirror action, using the IP address to find the hostname/domain name. You might be surprised that this is actually needed, but it has significant application. It is very useful for email verifications B2B and troubleshooting.

Imagine this situation, you don’t have a reverse DNS set up, but you are sending a very important email to another company. They have a mail server with Anti-Spam protection. It will check if you have rDNS and if you are missing it, your message will go directly to the spam bin. This protection reduces the phishing significantly by putting straight into the spam, all emails that have IPs that don’t correspond to IPs of the domains they say they come from.

All devices connected to the internet have their IP addresses. This makes it easy to do a reverse DNS lookup and see who it is on the other side. For this purpose, you will need a PTR record.

Check out Reverse DNS service by ClouDNS!

Why is rDNS important?

There are several reasons why rDNS is crucial. Some of them are the following: 

• Email Authentication: rDNS helps authenticate email servers and prevent spam. A large number of email servers will only accept incoming emails from hosts with a valid PTR record. That way, they avoid spam and phishing emails from spoofed IP addresses.
• Network Troubleshooting: rDNS can be used to help troubleshoot network issues. If a network administrator is trying to diagnose a problem with a specific IP address, they can use rDNS to determine which hostname is associated with it. This can help them identify the device or service causing the problem.
• Protection: Some security systems use rDNS to identify and block malicious traffic. For example, some intrusion detection and prevention systems will use rDNS to recognize and stop traffic coming from known malicious IP addresses.
• Access Control: In some cases, rDNS can be used to control access to a network or specific services. For example, some firewalls and VPNs use rDNS to allow or deny access to particular hosts or services based on their hostname.

How does rDNS work?

The main goal of rDNS is to map an IP address to a hostname. In order to achieve that, it works by performing a reverse lookup of an IP address to find the associated domain name.

The process of rDNS starts with a query to a DNS server, asking for the hostname associated with a specific IP address. The DNS server then looks up the available IP address in its records, and if it finds a match, it returns the associated hostname.

Reversing the forward DNS process and resolving an IP address to a domain name requires a Reverse DNS zone and a PTR record. So, let’s explain a little bit more about them!

PTR record

The PTR record is also called a Pointer record, and its primary purpose is to link the IP address to its corresponding hostname/domain name. It is important to note that you should have an A or AAAA record for each PTR record you create. The explanation behind this practice is pretty simple. An A record or AAAA record maps a hostname/domain name to its IP address, and PTR goes exactly in the opposite direction. That is why it is essential to ensure you configure your DNS records accurately without any mistakes. Otherwise, there is a possibility for your emails to land directly into the spam folder of your recipients.

Reverse DNS zone

Using rDNS requires creating a special type of DNS zone called a Reverse DNS zone. That is the only place where PTR records are able to exist and function correctly. Reverse DNS can work both with IPv4 addresses and IPv6 addresses, yet they should be written in reverse. That is because there is a specific root domain in-addr.arpa that uses the IP addresses in reverse order. So, for example, the IP address 111.123.101.1 becomes 1.101.123.111.in-addr.arpa.

How to start using rDNS?

The first step is to create a Reverse DNS zone; you can do that from the Control Panel, add a new zone and click on the Master Reverse DNS zone.

Watch the video to find out how to add Master Reverse DNS zone

This zone is directly related to the size of your IP network. For example in IPv4/24 network, you will have 255 IP addresses. In the network 192.168.1.0/24, all the available IPs will be from 192.168.1.1 to 192.168.1.255, and the Reverse DNS zone will have this format 1.168.192.in-addr.arpa

Now in this Reverse zone, we can add PTR records that match each IP from the network. You just add a new record; this will be for the first IP 192.168.1.1

Type: PTR

Host: 1

Points to: hostname1.example.com

The PTR records will look like this in the Control Panel:

Then, make sure that there is a matching A record. Each PTR must have one.

Find more information about PTR records and how to create them!

The last step is to change the name servers of your Reverse zone at your IP provider or ask them to do it. A configured NS records at the IP provider must point to the name servers listed in your Control Panel.

What in-addr.arpa is?

in-addr.arpa is a critical component in the architecture of Reverse DNS (rDNS), playing a pivotal role in how rDNS functions. This special domain is used specifically for mapping IP addresses to domain names, which is the essence of rDNS. Here’s a concise overview:

• Purpose: Used for IPv4 reverse DNS lookups, in-addr.arpa facilitates the conversion of IP addresses into a format suitable for DNS queries. This process is vital for various network services, especially email authentication.
• How it works: An IP address like 192.0.2.1 reverses to “1.2.0.192.in-addr.arpa“. A DNS query for this domain retrieves the associated domain name via a PTR record, crucial for verifying communication sources.
• IPv6 addresses: For IPv6, a similar domain called “ip6.arpa” is used, reflecting the distinct structure of these addresses.
• Management: Managed by IANA, in-addr.arpa’s namespace is partly delegated to ISPs for localized reverse DNS record management.

In essence, in-addr.arpa underpins rDNS, crucial for network integrity and cybersecurity efforts.

rDNS lookup – How to do it?

Now that we have explained the basics of rDNS, it’s time to show you how to perform an rDNS lookup. Besides, the process is simple, and you don’t need to have a background in IT to complete it. 

• Windows

If you are a Windows user, you can perform rDNS lookup with the NSlookup command. First, open the Command Prompt by pressing the Windows key + R, then typing “cmd” and pressing Enter. Type the following command:

$ nslookup 1.2.3.4

• macOS and Linux

If you are a macOS or Linux user, you can complete the rDNS lookup with the Dig command or the Host command. Open the Terminal application and write the following:

$ dig -x 1.2.3.4

or 

$ host -t PTR 1.2.3.4

*Please, make sure to replace “1.2.3.4” with the IP address (IPv4 or IPv6) you wish to check.

It’s important to note that in some cases, the rDNS lookup may not return any results if the IP address does not have a PTR record associated with it. Besides, in other cases, the response may show “NXDOMAIN” or “NXRRset”. Also, some firewalls or security systems may block reverse DNS queries.

Comparing rDNS and Forward DNS

Understanding the differences and interactions between Reverse DNS (rDNS) and Forward DNS is crucial in grasping internet infrastructure’s full scope.

Forward DNS is the process that converts human-readable domain names (like www.example.com) into IP addresses (like 192.168.1.1). This conversion is essential for internet navigation, allowing users to access websites without memorizing complex numeric addresses.

On the other hand, Reverse DNS (rDNS) works in the opposite direction. It takes an IP address and returns the corresponding domain name. This process is particularly important in scenarios where knowing the source of a network request is crucial. For example, when an email server receives a message, it might use rDNS to verify that the IP address of the sender matches the domain name claimed in the email. This verification helps in filtering out spam or spoofed emails.

The interaction between these two systems is symbiotic. While forward DNS is primarily used for routing internet traffic to the correct destinations, rDNS plays a key role in authentication and security. Together, they form a comprehensive system for both reaching and validating internet entities.

Conclusion

rDNS is essential for email authentication, network security, and troubleshooting network issues. It performs a reverse lookup of an IP address to find the associated hostname. To achieve that, creating a Reverse DNS zone and adding PTR records is required. Thanks to this amazing technology, the Internet is a more secure place by identifying the authenticity of the source of the email, and it is beneficial for network troubleshooting.

30-day Free Trial for Premium Anycast DNS hosting

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