A CLI Ruby program which does domain name resolution and prints the lookup chain, until it resolves to an IPv4 address.
learn more about DNS & zone files
RECORD TYPE
, SOURCE
, DESTINATION
A, ruby-lang.org, 221.186.184.75
A, google.com, 172.217.163.46
CNAME, www.ruby-lang.org, ruby-lang.org
CNAME, mail.google.com, google.com
CNAME, gmail.com, mail.google.com
$ ruby lookup.rb google.com
google.com => 172.217.163.46
$ ruby lookup.rb gmail.com
gmail.com => mail.google.com => google.com => 172.217.163.46
$ ruby lookup.rb gmil.com
gmil.com => Error: record not found for gmil.com