Ns Lookup

Ns Lookup

The basic definition of Ns lookup is the program that is used to look up an internet server’s administrator or any computer user.  It can be compared to a reverse name or phone number look up.

The way it works is that the Ns lookup sends out a query packet to a specific DNS server.  This functionality used to not be available for Windows users until Windows XP.  Now you can do this with windows from the command prompt.

To use the Windows version, open a command prompt and launch the tool as follows:

C:\> nslookup
Default Server: resolver1.opendns.com

Ns lookup can be used to troubleshoot and debug DNS problems. You can also look up mail servers with this command. When using about.com for example to look up a mail server, you will use the following code.

\> set type=mx

\> about.com

about.com MX preference = 100, mail exchanger = about.com.mail9.psmtp.com

about.com MX preference = 200, mail exchanger = about.com.mail10.psmtp.com

about.com MX preference = 300, mail exchanger = about.com.mail11.psmtp.com

about.com MX preference = 400, mail exchanger = about.com.mail12.psmtp.com

The Ns lookup has two operating modes.  The first one is the interactive mode.  This mode allows for the user to query the DNS-Server about various hosts and domains.  The other mode is non-interactive mode.  This allows the user to query the information for a host or domain.

There are many things that you can do with this information some of them are the following,  Query the MX Record, Query the NS Record, Query the SOA Record, view available DNS records, reverse DNS lookup, change the port number to connect with, change timeout interval to wait for a reply, and enabling debug mode using.