Perform DNS Lookups with the host command

By | 2012/04/26

The dig command is commonly used to make DNS queries. However, a much overlooked command is the host command. Here are some quick tips for a useful tool to add to your bag of tricks or to impress your friends.


The syntax is:

$ host [domain.com]


When run with no options, a simple quick summary is output:

$ host google.com
google.com has address 72.14.204.113
google.com has address 72.14.204.138
google.com has address 72.14.204.102
google.com has address 72.14.204.100
google.com has address 72.14.204.101
google.com mail is handled by 10 aspmx.l.google.com.
google.com mail is handled by 50 alt4.aspmx.l.google.com.
google.com mail is handled by 40 alt3.aspmx.l.google.com.
google.com mail is handled by 30 alt2.aspmx.l.google.com.
google.com mail is handled by 20 alt1.aspmx.l.google.com.

Using tack a is the equivalent of any ANY request:

$ host -a google.com
Trying "google.com"
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 57800
;; flags: qr rd ra; QUERY: 1, ANSWER: 9, AUTHORITY: 0, ADDITIONAL: 0

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

;; ANSWER SECTION:
google.com.             296     IN      MX      10 aspmx.l.google.com.
google.com.             296     IN      MX      50 alt4.aspmx.l.google.com.
google.com.             296     IN      MX      40 alt3.aspmx.l.google.com.
google.com.             296     IN      MX      30 alt2.aspmx.l.google.com.
google.com.             296     IN      MX      20 alt1.aspmx.l.google.com.
google.com.             170005  IN      NS      ns2.google.com.
google.com.             170005  IN      NS      ns1.google.com.
google.com.             170005  IN      NS      ns3.google.com.
google.com.             170005  IN      NS      ns4.google.com.

Received 208 bytes from 208.67.222.222#53 in 59 ms

Tack t followed by the type desired such as CNAME, NS, A, AAAA and so forth is a quick way to check for a specific type. This is a quick way to check for an ipv6 record, as one example:

$ host -t AAAA ipv6.google.com
ipv6.google.com is an alias for ipv6.l.google.com.
ipv6.l.google.com has IPv6 address 2001:4860:800a::69

Cool!