Different cases with down hosts

fast-mongo.rb

require 'mongo'
#Here I don't have any mongod listening on port 29017
client = Mongo::Client.new([ "127.0.0.1:29017", '127.0.0.1:27017' ], :database => 'test')
result = client[:artists].insert_one({ name: 'FKA Twigs' })

slow-mongo.rb

require 'mongo'
client = Mongo::Client.new([ "8.8.8.8:27017", '127.0.0.1:27017' ], :database => 'test')
result = client[:artists].insert_one({ name: 'FKA Twigs' })