run multiple commands, return interleaved output prefixed with hostname

run_command_prefix_example.rb

require 'open3'
hosts = %w{ host1 host2 host3 host4 host5 host6 }
commands = []
hosts.each do |host|
  handles = Open3.popen2e("echo", "#{host}") #replace with ssh call or whathaveyou
  handles << host
  handles = [:input, :output, :thread, :host].zip(handles)
  commands << Hash[handles]
end

while commands.any? do
  commands.each do |command|
    if command[:output].eof
      commands.delete(command)
    else
      puts "#{command[:host]}:#{command[:output].readline}"
    end
  end
end