var http = require('http'),
httpProxy = require('http-proxy');

 var servers =  [{host :'127.0.0.1', port :8081}, {host : '127.0.0.1',port :8082}];

  httpProxy.createServer(function (req, res, proxy) {

  var target = servers.shift();
  proxy.proxyRequest(req, res, target);
  servers.push(target);


   }).listen(8000);



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listen(8080, '127.0.0.1');