def get_lb_hostname_input
      lb_hostname_input = "text:"
      fe_servers.each do |fe|
        timeout = 30
        loopcounter = 0
        begin
          if fe.settings['private-dns-name'] == nil
            raise "FATAL: private DNS name is empty" if loopcounter > 10
            sleep(timeout)
            loopcounter += 1
            next
          end
          lb_hostname_input << fe.settings['private-dns-name'] + " "
          done = true
        end while !done
      end
      lb_hostname_input
    end
def get_lb_hostname_input
      lb_hostname_input = "text:"
      fe_servers.each do |fe|
        timeout = 30
        loopcounter = 0
        begin
          if fe.settings['private-dns-name'] == nil
            raise "FATAL: private DNS name is empty" if loopcounter > 10
            sleep(timeout)
            loopcounter += 1
            next
          end
          lb_hostname_input << fe.settings['private-dns-name'] + " "
          done = true
        end while !done
      end
      lb_hostname_input
    end
returns String with all the private dns of the Front End servers
 used for setting the LB_HOSTNAME input.