nslookup is a network administration command-line tool available in many computer operating systems for querying the Domain Name System (DNS) to obtain domain name or IP address mapping, or other DNS records information. The name “nslookup” means “name server lookup”
There are many options can be used in nslookup command however we will use some of them in this article.
command syntax
nslookup [option]
nslookup google.com
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nslookup -type=a google.com
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nslookup with domain name or -type=a will display the A Record (IP Address) of the domain. here google.com is a domain name. Use these commands to find the IP address or A record for a domain.
nslookup 8.8.8.8
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If you want to see reverse DNS lookup use IP address with nslookup command
nslookup -type=any google.com
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Above command will display all available DNS records of domain google.com
nslookup -type=ns google.com
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You can use -type=ns with nslookup command to get Name Servers of the domain.
nslookup -type=mx google.com
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MX stands for Mail Exchanger which is email server, run above command to see mail server of a domain.
nslookup -type=txt google.com
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TXT records can be used for many purposes like SPF, DKIM, DMARC records etc if you want to see all of them use option -type=txt with nslookup command.