Linux: whois command line

             whois searches Whois servers for the object on the command line.

       The  host  to  query  is  taken from a global configuration file, a configuration file specified on the command
       line, or selected directly on the command line.

[root@ayse~]# whois 1.1.1.1
[Querying whois.arin.net]
[Redirected to whois.apnic.net]
[Querying whois.apnic.net]
[whois.apnic.net]
% [whois.apnic.net]
% Whois data copyright terms    http://www.apnic.net/db/dbcopyright.html

% Information related to '1.1.1.0 - 1.1.1.255'
...


[root@ayse~]# whois wikipedia.org
...

Linux: perform Manual DNS Queries with dig tool

dig (domain information groper) is a flexible tool for interrogating DNS name servers. It performs DNS lookups and displays the answers that are returned from the name server(s) that were queried. Most DNS administrators use dig to troubleshoot DNS problems because of its flexibility, ease of use and clarity of output. Other lookup tools tend to have less functionality than dig.

[root@ayse ~]# dig +short NS trakya.edu.tr @8.8.8.8
tubimdc.trakya.edu.tr.
tubim.trakya.edu.tr.
[root@ayse ~]# dig +short A www.trakya.edu.tr @tubimdc.trakya.edu.tr
193.255.140.50
[root@ayse~]# dig +short MX trakya.edu.tr @tubimdc.trakya.edu.tr
0 mail.trakya.edu.tr.
[root@ayse~]# dig +short A mail.trakya.edu.tr @tubimdc.trakya.edu.tr
193.255.140.16
[root@ayse~]#