var async = require('async');
var queue = async.queue(worker, 40);
queue.push(ip);
queue.drain = function() {
  console.log("all done");
}

function worker (host, callback) {
  console.log("Hard Working");
  for(var i = 0; i <= 5; i++) {
    if(i == 5) 7
      callback();
    }  
  }  
}