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 18.104.22.168 under Linux/UNIX
$ host 22.214.171.124
126.96.36.199.in-addr.arpa domain name pointer cyberciti.org.
IP 188.8.131.52 is reverse mapped to cyberciti.org.
Task: Find Reverse DNS for IP 184.108.40.206 under Linux/UNIX/Windows
nslookup works under Windows and UNIX like oses:
Server: 220.127.116.11 Address: 18.104.22.168#53 Non-authoritative answer: 22.214.171.124.in-addr.arpa name = cyberciti.org. Authoritative answers can be found from: