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Created: 2016-05-03 08:48:20 -0700 Modified: 2016-05-03 08:54:51 -0700

NodeJS provides a ‘cluster’ module by default. This allows you to start the same program in many different processes and communicate between them.

You should likely perform logging by sending all log messages over a cluster transport if cluster.isWorker is true. To accomplish this:

  • Master
    • worker.on(‘message’, handlerFunction)
  • Worker
    • process.send({type: ‘log’, text: ‘blah’});

The basic template looks something like what’s coded below. Basically, the master needs to specify a custom port for “—debug” for all workers so that they aren’t all listening on the same port.

const env = {

anyEnvVars: ‘go here’


// If ‘—debug’ was specified as a flag to the master, then we’ll pass that off

// to the workers with their own specific debugger ports.


// Note: despite having ‘—debug’ specified, you may still need to hit the Pause

// button in Chrome or put a ‘debugger’ at the beginning of the game server

// worker.


// Note #2: you do not need —debug running on the master in order to debug

// workers.

const debug = process.execArgv.indexOf(‘—debug’) !== -1;


execArgv: process.execArgv.filter((arg) => arg !== ‘—debug’)


if (debug) {

cluster.settings.execArgv.push(‘—debug=’ + (5859 + workerId));



if (debug) {