ActiveDirectoryAuth.rb

require 'net/ldap'

LDAP_Servers_Transit = ['trn02svpdc01',  'trn02svpdc02']
LDAP_Servers_Corporate = ['cowsvpdc01', 'cowsvpdc02', 'cowsvpdc03', 'cowsvpdc04', 'cowsvpdc05']

def authenticate(user_name, password, ldap_servers = LDAP_Servers_Transit, port = 389)
    ldap_servers.each do |server|
    begin
      # Try to connect to the LDAP server as the user
      ldap = Net::LDAP.new( {:host => server, :port => port, :auth => { :method => :simple, :username => user_name, :password => password }} )
      return ldap.bind
    rescue Net::LDAP::LdapError
      # Log failure and try next server
      puts "Error connecting to server #{server}"
    end
  end
  false # Unable to connect to any of the servers
end

user_id = 'slamotte'
password = 'pw'

if authenticate(user_id, password)
  puts 'Authenticated'
else
  puts 'Not Authenticated'
end

if authenticate("cowdmp01\\#{user_id}", password, LDAP_Servers_Corporate)
  puts 'Authenticated'
else
  puts 'Not Authenticated'
end