how to scale a socket.io application on multiple servers?

1
votes

I have read a lot of stuff about custering, redis but I could not find any real sample.

I have a simple socket.io application and I need to scale this application to many servers.

Looks like socket.io and RedisStore is the solution.

Does anyone has a real world nippet on how he uses socket.io on many servers ?

1
node.jsredissocket.io

1 Answers

2
votes

You need to npm install the package socket.io-redis. Then start the server by command redis-server. Add the following lines to your code.

var io = require('socket.io')(3000);
var redis = require('socket.io-redis');
io.adapter(redis({ host: 'localhost', port: 6379 }));

Then you need to modify your nginx configurations file to enable load balancing as in, http://socket.io/docs/using-multiple-nodes/#nginx-configuration

upstream io_nodes {
   ip_hash;
   server 127.0.0.1:6001;
   server 127.0.0.1:6002;
   server 127.0.0.1:6003;
   server 127.0.0.1:6004;
}

Restart your nginx server and then run node server. This should scale your server too.