What is Reverse DNS?

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Reverse DNS (Domain Name System) lookup, also recognized by the acronym (rDNS), is the method by which somebody can appear up a host name given a certain IP address. Reverse DNS is also recognized in some places as reverse resolving. It is the opposite of DNS lookup, by which someone looks up an IP address given a specific host name.

Why use Reverse DNS?

A reverse DNS lookup is normally performed for troubleshooting purposes. Generally, tools like a traceroute or a ping will do a reverse DNS lookup to establish the flow of visitors from one point to one more. Yet another widespread place for reverse DNS lookup is when accessing a persons e mail. Numerous modern day e mail internet defending murder providers will do reverse DNS lookups to decide if an e mail was sent from a identified spam address. Lastly, reverse DNS can be employed to make confident that there is a suitable relationship amongst the owner of a server and the owner of a domain name. This strategy, recognized as Forward Confirmed reverse DNS (FCrDNS) the restraining order san diego is employed to place a stop to phishing internet sites and spammers.

What is IPv4 Reverse DNS lookup?

IPv4 Reverse DNS is a type of reverse DNS that makes use of a reverse IN-ADDR entry with the special domain in-addr.arpa. The IP address represented in the in-addr.arpa domain is written in reverse order to the usual way that the IP address is written. For instance, if a individual was performing a reverse domain lookup for an address such as 192.168.1.1, he would do the lookup go here for more info making use of 1.1.168.192.in-addr.arpa.

What is IPv6 Reverse DNS lookup?

IPv6 Reverse DNS lookup is a type of reverse DNS that uses the unique domain ip6.arpa. In contrast to IPv4 Reverse DNS lookup, IPv6 Reverse DNS lookup does not use the regular IP address style of seeking up host names. Instead, it utilizes a sequence of nibbles, or four bit aggregations, in reverse order with every quantity separated by a period. For instance, if a individual was performing a reverse domain lookup for an address such as 2001:0db8:::::1428:57ab he would do the lookup utilizing b.a.7.five.8.2.four.1.....8.b.d..1...two.ip6.arpa.

What takes place when there are many host names assigned to a single IP address?

A reverse DNS lookup will be able to figure out all of the host names connected with a specific IP address, though this practice is at times frowned upon. Numerous cheap web hosting plans will offer you shared virtual hosts where many web sites share space on the exact same IP address. Even though this does not impact the validity of the information returned by a reverse DNS lookup, it can lead to difficulties with other services.