~Delete 38038

Reverse DNS (Domain Name System) lookup, also identified by the acronym (rDNS), is the approach by which someone can appear up a host name given a particular IP address. Reverse DNS is also known in some areas as reverse resolving. It is the opposite of DNS lookup, by which a person looks up an IP address given a particular host name.

Why use Reverse DNS?

A reverse cruets DNS lookup is generally performed for troubleshooting purposes. Frequently, tools like a traceroute or a ping will do a reverse DNS lookup to decide the flow of targeted traffic from one point to one more. Another typical place for reverse DNS lookup is when accessing a persons e mail. A lot of contemporary email providers will do reverse DNS lookups to establish if an e-mail was sent from a known spam address. Lastly, reverse DNS can be utilized to make confident that there is a proper relationship amongst mustard seed the owner of a server and the owner of a domain name. This strategy, recognized as Forward Confirmed reverse DNS (FCrDNS) is employed to put 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 unique 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 person was performing a reverse domain lookup for an address such as 192.168.1.1, he would do the lookup using 1.1.168.192.in-addr.arpa.

What is IPv6 Reverse DNS lookup?

IPv6 Reverse DNS lookup is a sort of reverse DNS that makes use of the unique domain ip6.arpa. As opposed to IPv4 Reverse DNS lookup, IPv6 Reverse DNS lookup does not use the standard IP address style of looking up host names. As an alternative, it utilizes a sequence of nibbles, or 4 bit aggregations, in reverse order with every single quantity separated by a period. For example, if a person 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.two.4.1.....8.b.d..1...2.ip6.arpa.

What happens when there are numerous host names best kneeler assigned to 1 IP address?

A reverse DNS lookup will be able to decide all of the host names related with a particular IP address, even though this practice is at times frowned upon. A lot of low cost web hosting plans will offer you shared virtual hosts exactly where numerous web sites share space on the very same IP address. Though this does not have an effect on the validity of the info returned by a reverse DNS lookup, it can lead to difficulties with other services.