Simple DNS mx check

#!/usr/bin/env ruby

def check

 if ARGV[0] == nil

 abort 'plz input domain name'

 end

end

check

require 'resolv'

dns = Resolv::DNS.new

domain = ARGV[0]

dns.each_resource(domain, Resolv::DNS::Resource::IN::MX) do |mail_server|

 puts mail_server.exchange

end

#How to test

y-MacBook-Pro:rp young$ ruby mf.rb  

plz input domain name

y-MacBook-Pro:rp young$ ruby mf.rb yahoo.com

mta7.am0.yahoodns.net

mta5.am0.yahoodns.net

mta6.am0.yahoodns.net

y-MacBook-Pro:rp young$ ruby mf.rb nate.com

mx1.nate.com