Reverse DNS

Reverse DNS Lookup

These are the two types of DNS lookups: In a reverse DNS lookup, one tries to obtain the Hostname associated with an internet protocol address while a forward DNS lookup is one in which one gets the internet protocol address of a certain Hostname.

According to IETF, each domain should be capable of performing reverse DNS lookup, despite the fact that it is not mandatory because reverse lookups are not as crucial to the day-to-day functioning of the Internet as the forward lookups. Therefore, reverse DNS lookups are not popular.

Reverse lookups are used by email servers to verify that an email message that was received came from the correct server before it is allowed into the network. Messages from servers that do not support reverse lookups or that use generic domains may be rejected by the server.

Logging software applies reverse lookups in order to substitute the numbers of an IP address with a readable domain.