What is Reverse DNS?

Reverse DNS (Domain Name System) lookup, also known by the acronym (rDNS), is the approach by which someone can look up a host name given a particular IP address. Reverse DNS is also known in some places as reverse resolving. It is the opposite of DNS lookup, by which someone looks up an IP address given a particular host name. Why use Reverse DNS? A reverse DNS lookup is usually performed for troubleshooting purposes. Typically, tools like a traceroute or a ping will do a reverse DNS lookup to establish the flow of targeted traffic from one point to yet another. Another widespread spot for reverse DNS lookup is when accessing a persons e mail. Numerous modern e mail providers will do reverse DNS lookups to establish if an email was sent from a identified spam address. Lastly, reverse DNS can be used to make confident that there is a suitable relationship between the owner of a server and the owner of a domain name. This method, recognized as Forward Confirmed reverse DNS (FCrDNS) is utilised to place a quit to phishing internet sites and spammers. What is IPv4 Reverse DNS lookup? IPv4 Reverse DNS is a kind of reverse DNS that uses 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 example, if a individual was performing a reverse domain lookup for an address such as 192.168.1.1, he would do the lookup making use of 1.1.168.192.in-addr.arpa. What is IPv6 Reverse DNS lookup? IPv6 Reverse DNS lookup is a kind of reverse DNS that uses the special domain ip6.arpa. Unlike IPv4 Reverse DNS lookup, IPv6 Reverse DNS lookup does not use the common IP address style of seeking up host names. Instead, it makes use of a sequence of nibbles, or four bit aggregations, in reverse order with each quantity separated by a period. For example, if a individual was performing a reverse domain lookup for an address such as 2001:0db8:::::1428:57ab he would do the lookup using b.a.7.5.8.two.four.1.....eight.b.d..1...two.ip6.arpa. What happens when there are numerous host names assigned to a single IP address? A reverse DNS lookup will be able to decide all of the host names associated with a distinct IP address, even though this practice is occasionally frowned upon. Numerous low cost web hosting plans will supply shared virtual hosts exactly where many sites share space on the same IP address. Although this does not influence the validity of the information returned by a reverse DNS lookup, it can lead to issues with other services.

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Maira Rhodes For more appropriate data and information on how to find a person by phone number it is highly advisable to know how does laser hair removal work.

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