Q. How do I test or check reverse DNS for given IP address under Linux or Windows XP/Server 2003?
A. Reverse DNS lookup (also known as rDNS) is a process to determine the hostname associated with a given IP address.
Typically, the DNS is used to determine what IP address is associated with a given hostname; so to reverse resolve a known IP address is to lookup what the associated hostname for it. A reverse lookup is often referred to simply as reverse resolving, or more specifically reverse DNS lookups.
The most common uses of the reverse DNS are:
=> Network troubleshooting
=> Avoid spammers and phishers using a forward confirmed reverse DNS etc
You can use standard UNIX / Linux utilities such as nslookup, dig or hosts to find out reverse DNS of a given IP address.
Task: Find Reverse DNS for IP 22.214.171.124 under Linux/UNIX
$ host 126.96.36.199
188.8.131.52.in-addr.arpa domain name pointer cyberciti.org.
IP 184.108.40.206 is reverse mapped to cyberciti.org.
Task: Find Reverse DNS for IP 220.127.116.11 under Linux/UNIX/Windows
nslookup works under Windows and UNIX like oses:
Server: 18.104.22.168 Address: 22.214.171.124#53 Non-authoritative answer: 126.96.36.199.in-addr.arpa name = cyberciti.org. Authoritative answers can be found from:
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