Nslookup Command in Linux with Examples
Last Updated : 09 Apr, 2024
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.
In easy words, imagine the internet as a giant neighborhood. Websites are like houses, but instead of street names, they have easy-to-remember addresses like “google.com”. However, computers communicate using numbers, so they need a way to find these houses. That’s where DNS comes in. It acts like a phonebook, translating those friendly website names into numerical addresses (IP addresses) that computers can understand.
Now, the nslookup command is like a special tool you can use to explore this phonebook. It lets you ask questions about websites and how they’re connected. You can use it to:
- Look up a website’s address: Just like looking up a phone number in a phonebook, you can use
nslookup to find the IP address of a website. - Troubleshoot problems: If you’re having trouble accessing a website,
nslookup can help you pinpoint where the issue might lie. - Learn more about domain configurations: By using
nslookup, you can discover details about a website’s domain, such as the servers responsible for managing it.
Syntax of the nslookup Command in Linux
The syntax of the nslookup command is relatively straightforward, typically taking the form:
nslookup [option] [domain]
Where:
[options] refer to additional parameters that modify the behavior of the command.[domain] denotes the domain name or IP address to be queried.
Options of nslookup command:
| Options | Description |
| -domain=[domain-name] | allows you to change the default DNS name. |
| -debug | enables 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=a | Lookup 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=ns | 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. |
| -type=ptr | used in reverse DNS lookups. It retrieves the Pointer (PTR) records, which map IP addresses to domain names. |
| -type=soa | 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… |
Examples of Some Most Command Options of nslookup in Linux
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
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
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
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
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
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.
.jpg)
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
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.
Similar Reads
How to Read Manual Pages in Linux | man Command
The "man" command, short for manual, is a powerful tool in the Linux operating system that allows users to access detailed information about various commands, utilities, and system calls. The "man" command provides comprehensive documentation, helping users understand how to use and configure differ
9 min read
md5sum Command in Linux with Examples
The md5sum is designed to verify data integrity using MD5 (Message Digest Algorithm 5). MD5 is 128-bit cryptographic hash and if used properly it can be used to verify file authenticity and integrity. Example : Input : md5sum /home/mandeep/test/test.cppOutput : c6779ec2960296ed9a04f08d67f64422 /home
5 min read
How to Create Directory in Linux | mkdir Command
In Linux, the 'mkdir' command is like a magic wand for creating folders super easily. 'mkdir' stands for "make directory," and it helps you organize your computer stuff by creating folders with just one command. Whether you're making one folder or a bunch of them in a row, 'mkdir' is there to help y
7 min read
modinfo command in Linux with Examples
The modinfo command in Linux is used to display information about a Linux kernel module. It extracts detailed information from the modules available in the system and provides insights into their properties, dependencies, parameters, and more. If the module name is provided without a file name, the
3 min read
more command in Linux with Examples
The 'more' command in Linux is a useful tool for viewing text files in the command prompt, particularly when dealing with large files like log files. It displays the content one screen at a time, allowing users to scroll through the text easily. This command is especially handy for reviewing long ou
4 min read
How to Mount File System in Linux | mount Command
Working with file systems is a fundamental part of managing a Linux system, and knowing how to mount them is a skill every Linux user should have. Whether you’re connecting a USB drive, accessing a network share, or setting up a new partition, the mount command is your go-to tool for making file sys
7 min read
mpstat Command in Linux with Examples
mpstat is a powerful and versatile command-line tool within a Linux system that allows detailed reporting of various processor-related statistics. Indeed, part of the sysstat package, mpstat delivers comprehensive CPU utilization and performance data, thus becoming an essential utility for both syst
5 min read
How to Move File in Linux | mv Command
The `mv` command in Linux is like a superhero tool that can do a bunch of cool stuff with your files and folders. Think of it as a digital moving truck that helps you shift things around in your computer. Whether you want to tidy up your folders, give your files new names, or send them to different
7 min read
Practical Uses of nc(netcat) command in Linux
Netcat is one of the most powerful networking tools, security tools, and network monitoring tools. It is even considered a Swiss army knife of networking tools. It acts like a cat command over a network. It is generally used for the following reasons: Operation related to TCP, UDP, or UNIX-domain so
8 min read
Netstat command in Linux
The netstat command is like a special tool in Linux that helps you understand and check things about how your computer connects to the internet. It can tell you about the connections your computer is making, the paths it uses to send information, and even some technical details like how many packets
7 min read