Open In App
Related Articles

Nslookup Command in Linux with Examples

Improve
Improve
Improve
Like Article
Like
Save Article
Save
Report issue
Report

Nslookup (stands for “Name Server Lookup”) is a useful command for getting information from the DNS server. It is a network administration tool for querying the Domain Name System (DNS) to obtain domain name or IP address mapping or any other specific DNS record. It is also used to troubleshoot DNS-related problems. 

Syntax of the `nslookup` command in Linux System

nslookup [option] [hosts]

Options of nslookup command:  

OptionsDescription
-domain=[domain-name]allows you to change the default DNS name.
-debugenables the display of debugging information.
-port=[port-number]Use the -port option to specify the port number for queries. By default, nslookup uses port 53 for DNS queries
-timeout=[seconds]you can specify the time allowed for the DNS server to respond. By default, the timeout is set to a few seconds
-type=aLookup for a record 
We can also view all the available DNS records for a particular record using the -type=a option
-type=any Lookup for any record 
We can also view all the available DNS records using the -type=any option. 
-type=hinfo displays hardware-related information about the host. It provides details about the operating system and hardware platform
-type=mx  Lookup for an mx record 
MX (Mail Exchange) maps a domain name to a list of mail exchange servers for that domain. The MX record says that all the mails sent to “google.com” should be routed to the Mail server in that domain. 
-type=nsLookup for an ns record 
NS (Name Server) record maps a domain name to a list of DNS servers authoritative for that domain. It will output the name serves which are associated with the given domain. 
-type=ptr used in reverse DNS lookups. It retrieves the Pointer (PTR) records, which map IP addresses to domain names.
-type=soaLookup for a soa record 
SOA record (start of authority), provides the authoritative information about the domain, the e-mail address of the domain admin, the domain serial number, etc… 

Examples of Some Most Command Options of `nslookup` in Linux.

Performing a basic DNS lookup

Syntax:

nslookup example.com

Example:

nslookup google.com

nslookup followed by the domain name will display the “A Record” (IP Address) of the domain. Use this command to find the address record for a domain. It queries domain name servers and gets the details. 

nslookup google.com

nslookup google.com

Performing a reverse DNS lookup

Syntax:

nslookup [IP Address]

Example:

nslookup 192.168.0.10

 You can also do the reverse DNS look-up by providing the IP Address as an argument to nslookup. 

nslookup 192.168.0.10

nslookup 192.168.0.10

Using `-type=any` option 

Syntax:

nslookup -type=any google.com

 Lookup for any record We can also view all the available DNS records using the -type=any option. 

nslookup -type=any google.com

nslookup -type=any google.com

Using `-type=soa` option 

Syntax:

nslookup -type=soa redhat.com

Lookup for a soa record SOA record (start of authority), provides the authoritative information about the domain, the e-mail address of the domain admin, the domain serial number, etc… 

nslookup -type=soa redhat.com

nslookup -type=soa redhat.com

Using `-type=ns` option 

Syntax:

nslookup -type=ns google.com

 Lookup for an ns record. NS (Name Server) record maps a domain name to a list of DNS servers authoritative for that domain. It will output the name serves which are associated with the given domain. 

nslookup -type=ns google.com

nslookup -type=ns google.com

Using `-type=a` option 

Syntax:

nslookup -type=a google.com

Lookup for a record. We can also view all the available DNS records for a particular record using the -type=a option. 

nslookup -type=a google.com

Using `-type=mx` option 

Syntax:

nslookup -type=mx google.com

Lookup for an mx record. MX (Mail Exchange) maps a domain name to a list of mail exchange servers for that domain. The MX record says that all the mails sent to “google.com” should be routed to the Mail server in that domain. 

nslookup -type=mx google.com

nslookup -type=mx google.com

Using `-type=txt` option 

Syntax:

nslookup -type=txt google.com

Lookup for a txt record. TXT records are useful for multiple types of records like DKIM, SPF, etc. You can find all TXT records configured for any domain using the command below. 

nslookup -type=txt google.com

nslookup -type=txt google.com

Conclusion

In this article we have discussed the `nslookup` command which is a variable tool for querying the DNS server and obtaining information about domain name or IP address mapping. We have studied that it is very useful for troubleshooting DNS-related issues. We have also discussed options like -type=a, -type=any, -type=mx, -type=ns, -type=ptr, and -type=soa. Overall, we can say that by using nslookup information, administrators can gain insights into the DNS infrastructure and resolve DNS-related problems efficiently.


Last Updated : 09 Jun, 2023
Like Article
Save Article
Previous
Next
Share your thoughts in the comments
Similar Reads