What is Reverse DNS?

Reverse DNS (Domain Name System) lookup, also identified by the acronym (rDNS), is the procedure by which a person can appear up a host name given a specific IP address. Reverse DNS is also identified in some places as reverse resolving. It is the opposite of DNS lookup, by which someone looks up an IP address given a certain host name. Why use Reverse DNS? A reverse DNS lookup is typically performed for troubleshooting purposes.

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