dig | DNS Utilities

Dig (DNS Lookup) is a command-line utility used to query the Domain Name System (DNS) for information about domain names and their corresponding IP addresses. It’s a powerful tool for network administrators and system engineers to troubleshoot DNS issues, gather detailed information about DNS records, and analyze DNS traffic.

Basic Usage:

1. Open a command prompt or terminal: On Windows, you can access the command prompt by searching for “cmd” in the Start menu. On macOS or Linux, open a terminal application.
2. Type dig: This will start the dig tool in interactive mode.

Enter a domain name: Type the domain name you want to query and press Enter. For example:
dig example.com

3. View the results: Dig will display detailed information about the domain, including its IP address, DNS server used, DNS record types, and other relevant data.

Additional Options:

Specify DNS server: Use the @ symbol to specify a different DNS server to use for your queries. For example:
dig example.com @8.8.8.8

Check DNS records: Use the -t option to specify a specific DNS record type. For example, to check the MX records for a domain:
dig example.com -t MX

Perform a reverse lookup: Use the -x option to perform a reverse lookup, which translates an IP address into a domain name. For example:
dig -x 192.168.1.100

• Display additional information: Use the -v option to display verbose output, including more detailed information about the DNS query and response.

Example:

C:\> dig example.com

; <<>> DiG 9.11.5-9.11.5-P1 <<>> example.com

;; global options: +cmd=query +no-recurse +no-recursion +no-edns0 +no-udp-port=53

;; Got answer:

;; – 16323 bytes from 192.168.1.100#53(192.168.1.100), took 0.005 seconds

;; WARNING: No EDNS0 support available.

;; Got answer:

;; – 16323 bytes from 192.168.1.100#53(192.168.1.100), took 0.005 seconds

;; WARNING: No EDNS0 support available.

;; ANSWER SECTION:

example.com.  3600    IN        A          192.168.1.100

;; AUTHORITY SECTION:

example.com.  3600    IN        NS       ns1.example.com.

example.com.  3600    IN        NS       ns2.example.com.

;; ADDITIONAL SECTION:

ns1.example.com.       3600    IN        A          192.168.1.101

ns2.example.com.       3600    IN        A          192.168.1.102

In this example, dig queries the DNS server for the domain “example.com” and returns detailed information about its IP address, name servers, and other DNS records.

Troubleshooting DNS Issues with Dig:

• Check DNS server configuration: Ensure that your computer or device is configured to use the correct DNS servers.
• Verify domain registration: Make sure the domain name is registered and has been properly configured with DNS records.
• Check for DNS propagation: If you’ve recently made changes to DNS records, it may take some time for them to propagate across the internet.
• Look for errors: Dig will often display error messages if there are issues with the DNS query.

By understanding the basics of dig, you can effectively troubleshoot DNS problems, gather detailed information about DNS records, and analyze DNS traffic.