Linux Edu Handbook

Dig

The dig utility by Steve Hotz and Paul Mockapetris. This is a command-line tool for querying Domain Name System servers. It is much easier to use than nslookup, and is well-suited for use within shell scripts.

DIG Download mirror : ftp://ftp.cerias.purdue.edu/pub/tools/unix/sysutils/dig/

Examples of Dig Query

1) Request A Record

[root@darkstar ~]# dig linux.edu in a

; <<>> DiG 9.3.1 <<>> linux.edu in a
;; global options:  printcmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 11301
;; flags: qr; QUERY: 1, ANSWER: 1, AUTHORITY: 0, ADDITIONAL: 0

;; QUESTION SECTION:
;linux.edu.                     IN      A

;; ANSWER SECTION:
linux.edu.              604250  IN      A       208.176.116.21

;; Query time: 39 msec
;; SERVER: 212.27.53.252#53(212.27.53.252)
;; WHEN: Sun Apr  2 12:39:17 2006
;; MSG SIZE  rcvd: 43

[root@darkstar ~]#

2) Request NS Record

[root@darkstar ~]# dig linux.edu in NS

; <<>> DiG 9.3.1 <<>> linux.edu in NS
;; global options:  printcmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 23121
;; flags: qr; QUERY: 1, ANSWER: 3, AUTHORITY: 0, ADDITIONAL: 0

;; QUESTION SECTION:
;linux.edu.                     IN      NS

;; ANSWER SECTION:
linux.edu.              604800  IN      NS      ns2.signal1network.com.
linux.edu.              604800  IN      NS      ns1.signal1network.com.
linux.edu.              604800  IN      NS      master.linux.edu.

;; Query time: 1138 msec
;; SERVER: 212.27.54.252#53(212.27.54.252)
;; WHEN: Sun Apr  2 12:40:29 2006
;; MSG SIZE  rcvd: 102

[root@darkstar ~]#

3) Request SOA Record

[root@darkstar ~]# dig linux.edu in SOA

; <<>> DiG 9.3.1 <<>> linux.edu in SOA
;; global options:  printcmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 4849
;; flags: qr; QUERY: 1, ANSWER: 1, AUTHORITY: 0, ADDITIONAL: 0

;; QUESTION SECTION:
;linux.edu.                     IN      SOA

;; ANSWER SECTION:
linux.edu.              604800  IN      SOA     ns1.signal1network.com. eduard.linuxlabs.com. 2006040100 86400 7200 2592000 7200

;; Query time: 1139 msec
;; SERVER: 212.27.54.252#53(212.27.54.252)
;; WHEN: Sun Apr  2 12:40:55 2006
;; MSG SIZE  rcvd: 102

[root@darkstar ~]#

Documentation Advanced DNS documentation can be find in the DNS-HOWTO document.