Playing with whois & dig - getting all the a records (globally)

UNIX for Advanced & Expert Users
1

Dear All,

I want to get all the IPs of the A RECORDS for mail.google.com.
The aim is to deny access to these IPs.
I learnt that mail.google.com has several IPs.

I did the following steps:

  1. whois google.com
  2. I got the following as its DOMAIN SERVERS:

3.# dig @ns1.google.com a mail.google.com

;; ANSWER SECTION:
mail.google.com.    0    IN    CNAME    googlemail.l.google.com.
googlemail.l.google.com. 300    IN    A    74.125.233.86
googlemail.l.google.com. 300    IN    A    74.125.233.85

I thought this would give me all the IPs.:confused:

Currently, in an attempt to get the other IPs I am digging 4.2.2.2 & other free public dns servers..

someone please explain to me why

dig @ns1.google.com  a mail.google.com

does not give the full list & how other FreeDNS servers are getting different IPs?

2

No Answers :frowning: