DIG command is very flexible tool for shows domain information and DNS lookups you can easily find out your domain name servers, MX records, A records, AAAA Record, TXT Record and other related informations.

Find Domain Information:

The below commnad is prints name servers and A record of domain name.

# dig thelinuxfaq.com

;; ANSWER SECTION:
thelinuxfaq.com.    3600    IN    A    192.168.0.121

;; AUTHORITY SECTION:
thelinuxfaq.com.    172800    IN    NS    ns5.nameserver.com.
thelinuxfaq.com.    172800    IN    NS    ns6.nameserver.com.

;; ADDITIONAL SECTION:
ns5.nameserver.com.    163351    IN    A    192.168.0.121
ns6.nameserver.com.    163351    IN    A    192.168.0.122
#  dig thelinuxfaq.com +short

192.168.0.196
192.168.0.197


A  Record :

The A record maps a domain or subdomain to an IP address also we can say IP address points to domain name,
 
# dig redhat.com

;; ANSWER SECTION:
redhat.com.        60    IN    A    209.132.183.105

;; AUTHORITY SECTION:
redhat.com.        600    IN    NS    ns1.redhat.com.
redhat.com.        600    IN    NS    ns3.redhat.com.
redhat.com.        600    IN    NS    ns2.redhat.com.
redhat.com.        600    IN    NS    ns4.redhat.com.

;; ADDITIONAL SECTION:
ns1.redhat.com.        172799    IN    A    209.132.186.218
ns3.redhat.com.        172799    IN    A    209.132.176.100
ns4.redhat.com.        172799    IN    A    209.132.188.218
ns2.redhat.com.        172799    IN    A    209.132.183.2

 
# dig redhat.com A +short
209.132.183.105


AAAA Record:

AAAA record is same as A record, this record for IPv6 IP addresses. A typical AAAA record looks like,
 
# dig google.com AAAA

;; ANSWER SECTION:
google.com.        300    IN    AAAA    2404:6800:4003:c02::8b

;; AUTHORITY SECTION:
google.com.        111867    IN    NS    ns1.google.com.
google.com.        111867    IN    NS    ns4.google.com.
google.com.        111867    IN    NS    ns2.google.com.
google.com.        111867    IN    NS    ns3.google.com.

;; ADDITIONAL SECTION:
ns2.google.com.        111867    IN    A    216.239.34.10
ns1.google.com.        111867    IN    A    216.239.32.10
ns3.google.com.        111867    IN    A    216.239.36.10
ns4.google.com.        111867    IN    A    216.239.38.10

 
# dig google.com AAAA +short
2404:6800:4003:c02::8b


Name Server (NS):

NS spcefied to Name Servers, The NS record specifies an authoritative name server for given host. view your name servers which is pointing to your domain name,
 
# dig domainname.com NS

;; ANSWER SECTION:
domainname.com.        50915    IN    NS    ns2.nameserver.com.
domainname.com.        50915    IN    NS    ns1.nameserver.com.

;; Query time: 3 msec
;; SERVER: 127.0.1.1#53(127.0.1.1)
;; WHEN: Fri May 22 18:40:34 IST 2015
;; MSG SIZE  rcvd: 85

 
#  dig domainname.com NS +short

ns1.nameserver.com.
ns2.nameserver.com.


Mail Exchanger record (MX):

the MX record is used to sets the mail delivery destination for a domain name. 

The below command to view your domain MX record 
 
# dig domainname.com MX

;; QUESTION SECTION:
;domainname.com.            IN    MX

;; ANSWER SECTION:
domainname.com.        10041    IN    MX    0 domainname.com.

;; AUTHORITY SECTION:
domainname.com.        61837    IN    NS    ns2.nameserver.com.
domainname.com.        61837    IN    NS    ns1.nameserver.com.

;; ADDITIONAL SECTION:
domainname.com.        4265    IN    A    192.168.0.121

 
# dig domainname.com MX +short
0 domainname.com.


text record (TXT):

A TXT record provides about hold some text information to sources outside your domain. This can create an SPF record on nameservers also use to create a DKIM record for mail signing.
 
# dig domainname.com TXT

;; QUESTION SECTION:
;domainname.com.            IN    TXT

;; ANSWER SECTION:
domainname.com.        14400    IN    TXT    "v=spf1 ip4:192.168.0.121 a mx ~all"

;; AUTHORITY SECTION:
domainname.com.        61792    IN    NS    ns1.nameserver.com.
domainname.com.        61792    IN    NS    ns2.nameserver.com.

 
# dig domainname.com TXT +short
"v=spf1 ip4:192.168.0.121 a mx ~all"


Start of Authority (SOA):

SOA is information stored in a DNS zone with the name of the host where it was originally created,  Each zone contains a single SOA record,
 
# dig domainname.com SOA 

;; OPT PSEUDOSECTION:
; EDNS: version: 0, flags:; udp: 4096
;; QUESTION SECTION:
;domainname.com.            IN    SOA

;; ANSWER SECTION:
domainname.com.        86396    IN    SOA    ns1.nameserver.com. support.domainname.com. 2015031801 86400 7200 3600000 86400

;; AUTHORITY SECTION:
domainname.com.        50991    IN    NS    ns2.nameserver.com.
domainname.com.        50991    IN    NS    ns1.nameserver.com.

 
# dig domainname.com SOA +short
ns1.nameserver.com. support.domainname.com. 2015031801 86400 7200 3600000 86400


All DNS Pointing:
 
# dig domainname.com ANY 

;; QUESTION SECTION:
;domainname.com.            IN    ANY

;; ANSWER SECTION:
domainname.com.        14105    IN    TXT    "v=spf1 ip4:192.168.0.121 a mx ~all"
domainname.com.        9701    IN    MX    0 domainname.com.
domainname.com.        3925    IN    A    192.168.0.121
domainname.com.        61497    IN    NS    ns2.nameserver.com.
domainname.com.        61497    IN    NS    ns1.nameserver.com.

;; AUTHORITY SECTION:
domainname.com.        61497    IN    NS    ns1.nameserver.com.
domainname.com.        61497    IN    NS    ns2.nameserver.com.

;; ADDITIONAL SECTION:
domainname.com.        3925    IN    A    192.168.0.121


DNS Check from a Server:

Some time if you have configured DNS setting for specific domain on different server and to know whether configuration is right?, use below command  "@" symbol with that server IP address.
 
# dig domain2.com @192.168.0.191

;; QUESTION SECTION:
;domain2.com.            IN    A

;; ANSWER SECTION:
domain2.com.        3600    IN    A    192.168.0.197
domain2.com.        3600    IN    A    192.168.0.196

;; AUTHORITY SECTION:
domain2.com.        3600    IN    NS    ns5.dnsserver.com.
domain2.com.        3600    IN    NS    ns2.dnsserver.com.

;; ADDITIONAL SECTION:
ns1.dnsserver.com.    3600    IN    A    192.168.0.181
ns2.dnsserver.com.    3600    IN    A    192.168.0.191


Check Multiple domains :

If you need to check multiple domains at same time, create a file and add your domains, run the following command,
 
# dig -f domains.txt NS  +noall +answer

# dig -f domains.txt A  +noall +answer

# dig -f domains.txt CNAME  +noall +answer

# dig -f domains.txt TXT  +noall +answer

Version :

Check your dig version,
 
# dig -v
DiG 9.8.2rc1-RedHat-9.8.2-0.17.rc1.el6


Help:

Do you need more information about dig command,
 
# dig --help

# man dig