ruby script to change the passwords of remote servers using net-ssh

change_pwd.rb

require 'net/ssh'

hosts = IO.readlines('servers.txt') # full path of servers' list
port = 22                           # SSH port
user = 'root'                       # username
old_password = 'secret123'
new_password = 'secret@123'

hosts.each do |host|
  Net::SSH.start(host, user , :password => old_password , :port=> port) do |ssh|
    ssh.open_channel do |channel|
    channel.on_request "exit-status" do |channel, data|
      $exit_status = data.read_long
    end
      channel.request_pty do |channel, success| 
      channel.exec("sudo passwd UserName")  # Logged user shuold be root or sudoers memeber
      if success
        channel.on_data do |channel, data|
          puts data.inspect.chomp("\r\n")
          channel.send_data("#{new_password}\n") # put the New password you need to set
          sleep 0.1
        end
      else
        puts "FAILED!!"
      end
    end
    channel.wait
    puts "SUCCESS!!" if $exit_status == 0
    end
  end
end