Powerful DNS query tool - DIG

When we talk about the DNS query tool, we usually refer to nslookup. Now in this blog, we are going to talk about a more powerful tool called dig.

1.dig. Command without any parameters

root@ip-172-31-7-84:~# dig

; <<>> DiG 9.9.5-3-Ubuntu <<>>
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 25338
;; flags: qr rd ra; QUERY: 1, ANSWER: 13, AUTHORITY: 0, ADDITIONAL: 1

;; OPT PSEUDOSECTION:
; EDNS: version: 0, flags:; udp: 4096
;; QUESTION SECTION:
;.                              IN      NS

;; ANSWER SECTION:
.                       19664   IN      NS      d.root-servers.net.
.                       19664   IN      NS      e.root-servers.net.
.                       19664   IN      NS      f.root-servers.net.
.                       19664   IN      NS      g.root-servers.net.
.                       19664   IN      NS      h.root-servers.net.
.                       19664   IN      NS      i.root-servers.net.
.                       19664   IN      NS      j.root-servers.net.
.                       19664   IN      NS      k.root-servers.net.
.                       19664   IN      NS      l.root-servers.net.
.                       19664   IN      NS      m.root-servers.net.
.                       19664   IN      NS      a.root-servers.net.
.                       19664   IN      NS      b.root-servers.net.
.                       19664   IN      NS      c.root-servers.net.

;; Query time: 6 msec
;; SERVER: 172.31.0.2#53(172.31.0.2)
;; WHEN: Wed Jun 25 15:27:35 EST 2014
;; MSG SIZE  rcvd: 239

2.basic command: dig @DNS domain-name record-type

root@ip-172-31-7-84:~# dig @8.8.8.8 rms.nsw.gov.au AAAA

; <<>> DiG 9.9.5-3-Ubuntu <<>> @8.8.8.8 rms.nsw.gov.au AAAA
; (1 server found)
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 23205
;; flags: qr rd ra; QUERY: 1, ANSWER: 0, AUTHORITY: 1, ADDITIONAL: 1

;; OPT PSEUDOSECTION:
; EDNS: version: 0, flags:; udp: 512
;; QUESTION SECTION:
;rms.nsw.gov.au.                        IN      AAAA

;; AUTHORITY SECTION:
rms.nsw.gov.au.         1799    IN      SOA     dns2.rta.nsw.gov.au. root.dns2.rta.nsw.gov.au. 2013120601 7200 3600 3600000 7200

;; Query time: 289 msec
;; SERVER: 8.8.8.8#53(8.8.8.8)
;; WHEN: Wed Jun 25 15:29:14 EST 2014
;; MSG SIZE  rcvd: 93

3.common options: Here is the most common options we will need to keep in mind.
-t [type]: by default, it is A record(address) but you can set MX for query

root@ip-172-31-7-84:~# dig -t MX rms.nsw.gov.au

; <<>> DiG 9.9.5-3-Ubuntu <<>> -t MX rms.nsw.gov.au
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 41964
;; flags: qr rd ra; QUERY: 1, ANSWER: 7, AUTHORITY: 0, ADDITIONAL: 1

;; OPT PSEUDOSECTION:
; EDNS: version: 0, flags:; udp: 4096
;; QUESTION SECTION:
;rms.nsw.gov.au.                        IN      MX

;; ANSWER SECTION:
rms.nsw.gov.au.         7200    IN      MX      30 mx22out.rta.nsw.gov.au.
rms.nsw.gov.au.         7200    IN      MX      40 waterways-b1.maritime.nsw.gov.au.
rms.nsw.gov.au.         7200    IN      MX      10 cluster4.us.messagelabs.com.
rms.nsw.gov.au.         7200    IN      MX      20 cluster4a.us.messagelabs.com.
rms.nsw.gov.au.         7200    IN      MX      30 mx11out.rta.nsw.gov.au.
rms.nsw.gov.au.         7200    IN      MX      30 mx12out.rta.nsw.gov.au.
rms.nsw.gov.au.         7200    IN      MX      30 mx21out.rta.nsw.gov.au.

;; Query time: 14 msec
;; SERVER: 172.31.0.2#53(172.31.0.2)
;; WHEN: Wed Jun 25 15:31:10 EST 2014
;; MSG SIZE  rcvd: 250

-q [domain]: -q can be omitted, but it makes more clear if you add the –q option.

root@ip-172-31-7-84:~# dig -q www.google.com

; <<>> DiG 9.9.5-3-Ubuntu <<>> -q www.google.com
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 60498
;; flags: qr rd ra; QUERY: 1, ANSWER: 5, AUTHORITY: 0, ADDITIONAL: 1

;; OPT PSEUDOSECTION:
; EDNS: version: 0, flags:; udp: 4096
;; QUESTION SECTION:
;www.google.com.                        IN      A

;; ANSWER SECTION:
www.google.com.         166     IN      A       74.125.237.180
www.google.com.         166     IN      A       74.125.237.176
www.google.com.         166     IN      A       74.125.237.177
www.google.com.         166     IN      A       74.125.237.178
www.google.com.         166     IN      A       74.125.237.179

;; Query time: 6 msec
;; SERVER: 172.31.0.2#53(172.31.0.2)
;; WHEN: Wed Jun 25 15:33:07 EST 2014
;; MSG SIZE  rcvd: 123

-x [IP]: reverse query. Get the hostname for the IP.

root@ip-172-31-7-84:~# dig -x 193.0.14.129

; <<>> DiG 9.9.5-3-Ubuntu <<>> -x 193.0.14.129
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 19459
;; flags: qr rd ra; QUERY: 1, ANSWER: 1, AUTHORITY: 0, ADDITIONAL: 1

;; OPT PSEUDOSECTION:
; EDNS: version: 0, flags:; udp: 4096
;; QUESTION SECTION:
;129.14.0.193.in-addr.arpa.     IN      PTR

;; ANSWER SECTION:
129.14.0.193.in-addr.arpa. 21600 IN     PTR     k.root-servers.net.

;; Query time: 21 msec
;; SERVER: 172.31.0.2#53(172.31.0.2)
;; WHEN: Wed Jun 25 15:34:54 EST 2014
;; MSG SIZE  rcvd: 86

+tcp: use tcp for query.

root@ip-172-31-7-84:~# dig +tcp www.myrta.com

; <<>> DiG 9.9.5-3-Ubuntu <<>> +tcp www.myrta.com
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 27172
;; flags: qr rd ra; QUERY: 1, ANSWER: 1, AUTHORITY: 0, ADDITIONAL: 1

;; OPT PSEUDOSECTION:
; EDNS: version: 0, flags:; udp: 4096
;; QUESTION SECTION:
;www.myrta.com.                 IN      A

;; ANSWER SECTION:
www.myrta.com.          30      IN      A       163.189.7.175

;; Query time: 43 msec
;; SERVER: 172.31.0.2#53(172.31.0.2)
;; WHEN: Wed Jun 25 15:38:26 EST 2014
;; MSG SIZE  rcvd: 58

+trace: shows the trace path of the recursive path

root@ip-172-31-7-84:~# dig +trace www.myetoll.com
; <<>> DiG 9.9.5-3-Ubuntu <<>> +trace www.myetoll.com
;; global options: +cmd
.                       18934   IN      NS      l.root-servers.net.
.                       18934   IN      NS      m.root-servers.net.
.                       18934   IN      NS      a.root-servers.net.
.                       18934   IN      NS      b.root-servers.net.
.                       18934   IN      NS      c.root-servers.net.
.                       18934   IN      NS      d.root-servers.net.
.                       18934   IN      NS      e.root-servers.net.
.                       18934   IN      NS      f.root-servers.net.
.                       18934   IN      NS      g.root-servers.net.
.                       18934   IN      NS      h.root-servers.net.
.                       18934   IN      NS      i.root-servers.net.
.                       18934   IN      NS      j.root-servers.net.
.                       18934   IN      NS      k.root-servers.net.
;; Received 239 bytes from 172.31.0.2#53(172.31.0.2) in 14 ms

com.                    172800  IN      NS      k.gtld-servers.net.
com.                    172800  IN      NS      c.gtld-servers.net.
com.                    172800  IN      NS      j.gtld-servers.net.
com.                    172800  IN      NS      e.gtld-servers.net.
com.                    172800  IN      NS      a.gtld-servers.net.
com.                    172800  IN      NS      l.gtld-servers.net.
com.                    172800  IN      NS      m.gtld-servers.net.
com.                    172800  IN      NS      f.gtld-servers.net.
com.                    172800  IN      NS      b.gtld-servers.net.
com.                    172800  IN      NS      i.gtld-servers.net.
com.                    172800  IN      NS      h.gtld-servers.net.
com.                    172800  IN      NS      g.gtld-servers.net.
com.                    172800  IN      NS      d.gtld-servers.net.
com.                    86400   IN      DS      30909 8 2 E2D3C916F6DEEAC73294E8268FB5885044A833FC5459588F4A9184CF C41A5766
com.                    86400   IN      RRSIG   DS 8 1 86400 20140701000000 20140623230000 40926 . lDy4cb2Mb6tyMYXfCNX1bcEwE2Rg6OkcsuSv+R81yFHEG5/luQvypHHr nt6apJYVf30t748Dtu5X3H56IXXlgftqgY93AbuAjugAz3gf8YiQtRW5 wQcKjtzq2luW1YIVYtujntwfC4om+sVxtCJbKT88cqQUwyTvKr8D6SxS QtA=
;; Received 739 bytes from 192.36.148.17#53(i.root-servers.net) in 237 ms

myetoll.com.            172800  IN      NS      dns1.rta.nsw.gov.au.
myetoll.com.            172800  IN      NS      dns2.rta.nsw.gov.au.
CK0POJMG874LJREF7EFN8430QVIT8BSM.com. 86400 IN NSEC3 1 1 0 - CK0QFMDQRCSRU0651QLVA1JQB21IF7UR NS SOA RRSIG DNSKEY NSEC3PARAM
CK0POJMG874LJREF7EFN8430QVIT8BSM.com. 86400 IN RRSIG NSEC3 8 2 86400 20140630044832 20140623033832 56657 com. Co2ZGs6Fo2h2zlCv4wQS4E28nhjNxNQ/InfoiMq52MUH4/IJ9rh1Ot4C vuEmO3J1U4VVYUedu1EyFtBe6hGpajEfsntCYFA2EFbi2PgzAHAw8Ljr NCC24OnMBfcpbM6ew5UFd/157h6Tv/a+ilystE7+goWZi7q6Y6VNPWle B60=
RFJREQ8DI8OGS8V03LLBHDLV4J3EIPHK.com. 86400 IN NSEC3 1 1 0 - RFJVBCOQJUN2E7A6HEMG5MM79DAEKVMV NS DS RRSIG
RFJREQ8DI8OGS8V03LLBHDLV4J3EIPHK.com. 86400 IN RRSIG NSEC3 8 2 86400 20140701043512 20140624032512 56657 com. McX9ZVW1HVTK4ZkKSOOAj9pkHb8VzqKIbRNdcMWN8OJ75GaL/9II1bNx pXodneZpd+qtRe3TVhweJlv30zXEritWsN507cQDDsDoIgu+aNpgCzO7 louvilFNU88pOPPx4Wk1oTS9BNpNV/rcw0GWF/Yb/Y2Q/XTiyNl5NLe0 LiM=
;; Received 581 bytes from 192.12.94.30#53(e.gtld-servers.net) in 376 ms

www.myetoll.com.        7200    IN      NS      dns22.rta.nsw.gov.au.
www.myetoll.com.        7200    IN      NS      dns11.rta.nsw.gov.au.
;; Received 98 bytes from 163.189.23.22#53(dns2.rta.nsw.gov.au) in 26 ms

;; Received 12 bytes from 163.189.217.1#53(dns22.rta.nsw.gov.au) in 9 ms

+short: only show the result of the query.

root@ip-172-31-7-84:~# dig +short www.rms.nsw.gov.au
163.189.7.150