Using node.js to listen on 2 different ports

Just create another instance of http and put it to listen to the port you are interested. Let me show you an example:

var http = require('http');

http.createServer(onRequest_a).listen(9011);
http.createServer(onRequest_b).listen(9012);

function onRequest_a (req, res) {
  res.write('Response from 9011\n');
  res.end();
}

function onRequest_b (req, res) {
  res.write('Response from 9012\n');
  res.end();
}

Then, you can test it (with your browser, or curl):

$ curl http://localhost:9011
Response from 9011

$ curl http://localhost:9012
Response from 9012