Ring

gistfile1.js

// start node.js processes on a distributed network
// makes sure the process is always available, even if
// it has to restart the process on another server

// essentially a distributed version of forever

// no client/server relationship, all ring nodes are peers
var ring = require('ring').join('network guid')
  , opts = {
      distribution: {
        min: 3,
        max: 10
      }
    };

// - tell ring you want a process up no matter what
// - nodes on the ring keep eachother up to date
ring.start('my guid', opts, function(err, proc) {

  // stdout is available over
  // the network if needed
  proc.stdout.on('data', function (data) {
    process.stdout.write(data);
  });

  ring.list(function (err, processes) {
    // list all processes in
    // the entire ring
    console.log(processes);
  });

});

// - all events come across the network
// - death can be due to a fault or failure
//   to trigger a heartbeat event
ring.on('death', function (err, proc) {
  // by default ring will try to restart on the same machine,
  // if the proc cannot be brought up it will try another machine
  // until this callback gets an 'err' that the entire ring is down
});