Linux dig Command with Examples

The dig command, short for Domain Information Groper, is a powerful Linux command-line tool used to query the Domain Name System (DNS). DNS translates human-readable domain names such as www.example.com into IP addresses that computers can understand.

For university students learning Linux, networking, cloud computing, or cybersecurity, dig is an important command for understanding how DNS works and for troubleshooting domain-name problems.

What Does the dig Command Do?

The dig command sends a DNS query to a DNS server and displays the response. It can retrieve different types of DNS records, including:

A, AAAA, MX, NS, CNAME, and TXT records.

The basic syntax is:

$ dig [options] domain [record-type]

Find the IP Address of a Domain

The simplest use is to query the A record of a domain:

$ dig example.com

The response contains an ANSWER SECTION showing the IPv4 address associated with the domain.

You can also request only the IP address:

$ dig example.com +short

Example output:

93.184.216.34

Find IPv6 Address

To retrieve the AAAA record, which contains an IPv6 address, use:

$ dig example.com AAAA

Find Mail Servers

MX records identify the mail servers responsible for receiving email for a domain.

$ dig example.com MX

This is useful when studying how email delivery and DNS are connected.

Find Name Servers

To discover the authoritative DNS servers for a domain, query the NS record:

$ dig example.com NS

Name servers are responsible for providing DNS information about the domain.

Query a Specific DNS Server

You can tell dig which DNS server to use. For example, to query Google’s public DNS server:

$ dig @8.8.8.8 example.com

This is particularly useful for comparing responses from different DNS servers when troubleshooting DNS issues.

Check Different DNS Records

Some commonly used queries are:

$ dig example.com CNAME
$ dig example.com TXT
$ dig example.com SOA

These records can provide information about aliases, domain verification, email security policies, and DNS zone administration.

See Also:

nslookup Command

• https://www.testingdocs.com/linux-nslookup-command-with-examples/