View source for dig

=== Install dig package ===
Dig is part of package bind9-dnsutils.
<syntaxhighlight lang="bash">
$ apt-file list bind9-dnsutils
bind9-dnsutils: /usr/bin/delv             
bind9-dnsutils: /usr/bin/dig
bind9-dnsutils: /usr/bin/dnstap-read
bind9-dnsutils: /usr/bin/mdig
bind9-dnsutils: /usr/bin/nslookup
bind9-dnsutils: /usr/bin/nsupdate
bind9-dnsutils: /usr/share/doc/bind9-dnsutils/changelog.Debian.gz
bind9-dnsutils: /usr/share/doc/bind9-dnsutils/copyright
bind9-dnsutils: /usr/share/man/man1/delv.1.gz
bind9-dnsutils: /usr/share/man/man1/dig.1.gz
bind9-dnsutils: /usr/share/man/man1/dnstap-read.1.gz
bind9-dnsutils: /usr/share/man/man1/mdig.1.gz
bind9-dnsutils: /usr/share/man/man1/nslookup.1.gz
bind9-dnsutils: /usr/share/man/man1/nsupdate.1.gz
$ apt install bind9-dnsutils
</syntaxhighlight>
=== Download root server cache file ===
<syntaxhighlight lang="bash">
wget ftp://ftp.rs.internic.net/domain/named.cache
wget ftp://ftp.rs.internic.net/domain/db.cache
</syntaxhighlight>
=== Reverse lookup ===
This option sets simplified reverse lookups, for mapping addresses to names.
<syntaxhighlight lang="bash">
$ dig -x 54.239.28.85
</syntaxhighlight>

=== Check dig version ===
<syntaxhighlight lang="bash">
$ dig -v
</syntaxhighlight>
=== Find the ip of a host ===
<syntaxhighlight lang="bash">
$ dig amazon.com | grep -A 1 --color 'ANSWER SECTION'
;; ANSWER SECTION:
amazon.com.             842     IN      A       205.251.242.103

$ dig google.com +short
142.250.113.102
142.250.113.101
142.250.113.100
142.250.113.113
142.250.113.139
142.250.113.138

$ dig amazon.com +noall +answer
amazon.com.             325     IN      A       52.94.236.248
amazon.com.             325     IN      A       205.251.242.103
amazon.com.             325     IN      A       54.239.28.85
</syntaxhighlight>
Look at the "ANSWER SECTION", it has name, TTL in seconds, IN (class or internet), A (record type), IP.

=== Specify an exact DNS to search ===
<syntaxhighlight lang="bash">
$ dig @8.8.8.8 amazon.com
</syntaxhighlight>
=== List all DNS of a host ===
<syntaxhighlight lang="bash">
$ dig google.com A +nssearch
SOA ns1.google.com. dns-admin.google.com. 759020131 900 900 1800 60 from server 216.239.38.10 in 28 ms.
SOA ns1.google.com. dns-admin.google.com. 759020131 900 900 1800 60 from server 216.239.32.10 in 28 ms.
SOA ns1.google.com. dns-admin.google.com. 759020131 900 900 1800 60 from server 216.239.36.10 in 44 ms.
SOA ns1.google.com. dns-admin.google.com. 759020131 900 900 1800 60 from server 216.239.34.10 in 52 ms.
</syntaxhighlight>
=== Deep dive with trace ===
This option toggles tracing of the delegation path from the root name servers for the name being looked up. Tracing is disabled by default.  When  tracing is enabled, dig makes iterative queries to resolve the name being looked up. It follows referrals from the root servers, showing the answer from each server that was used to resolve the lookup.
<syntaxhighlight lang="bash">
$ dig amazon.com +trace
</syntaxhighlight>
=== 13 root servers ===
<syntaxhighlight lang="bash">
$ dig NS .

;; ANSWER SECTION:
.                       515350  IN      NS      k.root-servers.net.
.                       515350  IN      NS      l.root-servers.net.
.                       515350  IN      NS      m.root-servers.net.
.                       515350  IN      NS      a.root-servers.net.
.                       515350  IN      NS      b.root-servers.net.
.                       515350  IN      NS      c.root-servers.net.
.                       515350  IN      NS      d.root-servers.net.
.                       515350  IN      NS      e.root-servers.net.
.                       515350  IN      NS      f.root-servers.net.
.                       515350  IN      NS      g.root-servers.net.
.                       515350  IN      NS      h.root-servers.net.
.                       515350  IN      NS      i.root-servers.net.
.                       515350  IN      NS      j.root-servers.net.

;; ADDITIONAL SECTION:
h.root-servers.net.     601447  IN      A       198.97.190.53
i.root-servers.net.     601603  IN      A       192.36.148.17
k.root-servers.net.     601561  IN      A       193.0.14.129
</syntaxhighlight>
=== NS for com and gov ===
<syntaxhighlight lang="bash">
$ dig NS com @e.root-servers.net

;; AUTHORITY SECTION:
com.                    172800  IN      NS      a.gtld-servers.net.
com.                    172800  IN      NS      b.gtld-servers.net.
com.                    172800  IN      NS      c.gtld-servers.net.
com.                    172800  IN      NS      d.gtld-servers.net.
com.                    172800  IN      NS      e.gtld-servers.net.
com.                    172800  IN      NS      f.gtld-servers.net.
com.                    172800  IN      NS      g.gtld-servers.net.
com.                    172800  IN      NS      h.gtld-servers.net.
com.                    172800  IN      NS      i.gtld-servers.net.
com.                    172800  IN      NS      j.gtld-servers.net.
com.                    172800  IN      NS      k.gtld-servers.net.
com.                    172800  IN      NS      l.gtld-servers.net.
com.                    172800  IN      NS      m.gtld-servers.net.

;; ADDITIONAL SECTION:
a.gtld-servers.net.     172800  IN      A       192.5.6.30
a.gtld-servers.net.     172800  IN      AAAA    2001:503:a83e::2:30
b.gtld-servers.net.     172800  IN      A       192.33.14.30
b.gtld-servers.net.     172800  IN      AAAA    2001:503:231d::2:30
c.gtld-servers.net.     172800  IN      A       192.26.92.30
c.gtld-servers.net.     172800  IN      AAAA    2001:503:83eb::30
d.gtld-servers.net.     172800  IN      A       192.31.80.30
d.gtld-servers.net.     172800  IN      AAAA    2001:500:856e::30
e.gtld-servers.net.     172800  IN      A       192.12.94.30
e.gtld-servers.net.     172800  IN      AAAA    2001:502:1ca1::30
f.gtld-servers.net.     172800  IN      A       192.35.51.30
f.gtld-servers.net.     172800  IN      AAAA    2001:503:d414::30
g.gtld-servers.net.     172800  IN      A       192.42.93.30
g.gtld-servers.net.     172800  IN      AAAA    2001:503:eea3::30
h.gtld-servers.net.     172800  IN      A       192.54.112.30
h.gtld-servers.net.     172800  IN      AAAA    2001:502:8cc::30
i.gtld-servers.net.     172800  IN      A       192.43.172.30
i.gtld-servers.net.     172800  IN      AAAA    2001:503:39c1::30
j.gtld-servers.net.     172800  IN      A       192.48.79.30
j.gtld-servers.net.     172800  IN      AAAA    2001:502:7094::30
k.gtld-servers.net.     172800  IN      A       192.52.178.30
k.gtld-servers.net.     172800  IN      AAAA    2001:503:d2d::30
l.gtld-servers.net.     172800  IN      A       192.41.162.30
l.gtld-servers.net.     172800  IN      AAAA    2001:500:d937::30
m.gtld-servers.net.     172800  IN      A       192.55.83.30
m.gtld-servers.net.     172800  IN      AAAA    2001:501:b1f9::30

$ dig NS gov @e.root-servers.net
;; AUTHORITY SECTION:
gov.                    172800  IN      NS      a.ns.gov.
gov.                    172800  IN      NS      b.ns.gov.
gov.                    172800  IN      NS      c.ns.gov.
gov.                    172800  IN      NS      d.ns.gov.

;; ADDITIONAL SECTION:
a.ns.gov.               172800  IN      A       199.33.230.1
a.ns.gov.               172800  IN      AAAA    2001:503:ff40::1
b.ns.gov.               172800  IN      A       199.33.231.1
b.ns.gov.               172800  IN      AAAA    2001:503:ff41::1
c.ns.gov.               172800  IN      A       199.33.232.1
c.ns.gov.               172800  IN      AAAA    2001:503:ff42::1
d.ns.gov.               172800  IN      A       199.33.233.1
d.ns.gov.               172800  IN      AAAA    2001:503:ff43::1

</syntaxhighlight>
=== Get the Domain's name server ===
<syntaxhighlight lang="bash">
$ dig NS google.com @j.gtld-servers.net.
;; AUTHORITY SECTION:
google.com.             172800  IN      NS      ns2.google.com.
google.com.             172800  IN      NS      ns1.google.com.
google.com.             172800  IN      NS      ns3.google.com.
google.com.             172800  IN      NS      ns4.google.com.

;; ADDITIONAL SECTION:
ns2.google.com.         172800  IN      AAAA    2001:4860:4802:34::a
ns2.google.com.         172800  IN      A       216.239.34.10
ns1.google.com.         172800  IN      AAAA    2001:4860:4802:32::a
ns1.google.com.         172800  IN      A       216.239.32.10
ns3.google.com.         172800  IN      AAAA    2001:4860:4802:36::a
ns3.google.com.         172800  IN      A       216.239.36.10
ns4.google.com.         172800  IN      AAAA    2001:4860:4802:38::a
ns4.google.com.         172800  IN      A       216.239.38.10

</syntaxhighlight>
=== Get MX NS A records ===
<syntaxhighlight lang="bash">
$ dig MX yahoo.com
$ dig NS yahoo.com
$ dig A yahoo.com
</syntaxhighlight>
[[Category:Commands]]