6. DNS Tools

nslookup

The "name server lookup" tool is used to query name servers to find information about resource records. Let's find where the name server for google.com is:

pete@icebox:~$ nslookup www.google.com

Server:         127.0.1.1

Address:        127.0.1.1#53


Non-authoritative answer:

Name:   www.google.com

Address: 216.58.192.4

dig

Dig (domain information groper) is a powerful tool for getting information about DNS name servers, it is more flexible than nslookup and great for troubleshooting DNS issues.

pete@icebox:~$ dig www.google.com


; <<>> DiG 9.9.5-3-Ubuntu <<>> www.google.com

;; global options: +cmd

;; Got answer:

;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 42376

;; flags: qr rd ra; QUERY: 1, ANSWER: 5, AUTHORITY: 0, ADDITIONAL: 1

;; OPT PSEUDOSECTION:

; EDNS: version: 0, flags:; MBZ: 0005 , udp: 512

;; QUESTION SECTION:

;www.google.com.                        IN      A

;; ANSWER SECTION:

www.google.com.         5       IN      A       74.125.239.147

www.google.com.         5       IN      A       74.125.239.144

www.google.com.         5       IN      A       74.125.239.146

www.google.com.         5       IN      A       74.125.239.145

www.google.com.         5       IN      A       74.125.239.148

;; Query time: 27 msec

;; SERVER: 127.0.1.1#53(127.0.1.1)

;; WHEN: Sun Feb 07 10:14:00 PST 2016

;; MSG SIZE  rcvd: 123