How to Use dig Command in Linux: Syntax and Examples

The dig command in Linux is used to query DNS servers for information about domain names, such as IP addresses or mail servers. You run dig followed by a domain name and optional query type to get detailed DNS records.

Syntax

The basic syntax of the dig command is:

• dig [@server] [name] [type]

Here:

• @server is optional and specifies which DNS server to query (default is your system's DNS).
• name is the domain name you want to look up.
• type is the DNS record type you want (like A, MX, TXT, etc.).

bash

dig [@server] [name] [type]

Example

This example shows how to use dig to find the IP address (A record) of example.com:

bash

dig example.com A

Output

; <<>> DiG 9.18.1-1ubuntu1.3-Ubuntu <<>> example.com A
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 12345
;; flags: qr rd ra; QUERY: 1, ANSWER: 1, AUTHORITY: 0, ADDITIONAL: 1

;; QUESTION SECTION:
;example.com.                   IN      A

;; ANSWER SECTION:
example.com.            86399   IN      A       93.184.216.34

;; Query time: 20 msec
;; SERVER: 127.0.0.53#53(127.0.0.53)
;; WHEN: Thu Jun 15 12:00:00 UTC 2024
;; MSG SIZE  rcvd: 56

Common Pitfalls

Common mistakes when using dig include:

• Not specifying the query type, which defaults to A record but may not be what you want.
• Forgetting to use @server if you want to query a specific DNS server.
• Misreading the output sections; the ANSWER SECTION contains the useful data.

bash

dig example.com

dig @8.8.8.8 example.com MX

Quick Reference

Option	Description
@server	Query a specific DNS server (e.g., @8.8.8.8)
name	Domain name to query (e.g., example.com)
type	DNS record type (A, MX, TXT, NS, etc.)
+short	Show only the answer section for quick results
+trace	Trace the query path from root servers

Key Takeaways

Use dig [@server] [name] [type] to query DNS records.

Specify the DNS record type to get the exact information you need.

Use @server to query a specific DNS server.

Read the ANSWER SECTION in the output for the main results.

Use options like +short for simpler output.