Starting from createServer: https://github.com/nodejs/io.js/blob/master/lib/net.js#L884
Adding subscription to ‘connection’ event: https://github.com/nodejs/io.js/blob/master/lib/net.js#L1066
When listen is called, we are going here: https://github.com/nodejs/io.js/blob/master/lib/net.js#L1353
Cause’ we are worker, we’ll request a server: https://github.com/nodejs/io.js/blob/master/lib/net.js#L1254
_getServer is sending a message to master https://github.com/nodejs/io.js/blob/master/lib/cluster.js#L542