Question: What is the difference between forward and reverse DNS lookup?

Forward and reverse DNS lookup are commonly use in networking world and this is difference between them:

Forward DNS lookup is used to convert the human meaningful name (domain name) which is in easy to understand format to computer meaningful name (IP address), however reverse DNS lookup works in reverse way to convert IP address to domain name.

How to perform forward or reverse DNS lookup? Well, you can quickly use this nslookup tool in Windows OS to perform the lookup.

Forward DNS lookup is commonly used for website or other server accesses on Internet, because it’s easy to remember domain name instead of IP address. At the same time, several servers with different IP addresses that are converted to same domain name for load balancing can be used to provide better website access performance. As an example, is converted to IP address Whenever you try to access this website, you just need to key in in web browser’s address bar instead of using actual IP address.

forward DNS lookup

Usually reverse DNS lookup is used for network troubleshooting. During network troubleshooting, most of the time you will be interested to find out the domain name of the IP address that has problem or causes the problem, in this case this type of reverse lookup is useful. This is an example:

reverse DNS lookup

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