Does cluster support socket.io node?

[lexer]

Failed to find cluster google group. Does cluster support socket.io node?

[3rd-Eden]

No, because your polling requests could go to different servers where the sessionId might be unknown. But we are working on a Socket.IO (0.7) release that allows you scale over multiple processes.

[tj]

nope. like @3rd-Eden mentioned, it's more of an issue of socket.io not supporting multiple processes out of the box

[xepcoh]

Is it still the case with socket.io 0.8.4?

[3rd-Eden]

@dimux333 yes, it's still the case for 0.8.4, however!

We recently landed the RediStore backend for Socket.IO which does allow you to run cluster together with Socket.IO. I gave a small demo about this during my Nodejsconf.it session. You can find a working demo of this in my github repo (https://github.com/3rd-Eden/nodejsconfit-2011/tree/master/cluster) which will spawn a cluster of 40 processes with a working socket.io.

So support is definitely coming, but I was unable to get WebSockets working with Cluster but that could been the lack of time I had to fully investigate this behavior.

[xepcoh]

Thanks. I'll take a look.

[DavidChouinard]

@3rd-Eden & @xepcoh Sorry to revive this thread, but what's the status now? How's the support of Socket.io with Node's native cluster functionality?

[tj]

@DavidChouinard same thing as before, there's no such thing as "supporting node cluster", it's just the same-old multi-process issue, which you can get around by using redis etc

[3rd-Eden]

@DavidChouinard @visionmedia The advised way is to the RedisStore that is inside of Socket.IO (https://github.com/LearnBoost/socket.io/blob/master/lib/stores/redis.js) which will make sure that Socket.IO runs with the native cluster implementation of Nodejs and the leanboost/cluster module.

For usage see my nodejsconf-it example that I posted above.

[DavidChouinard]

@3rd-Eden

I copied the /socket/ directory of your repo (thanks!) and ran it. Every worker is spewing this error:

Error: Redis connection to 127.0.0.1:6379 failed - ECONNREFUSED, Connection refused
    at Socket.<anonymous> (/Users/david/Desktop/cluster/node_modules/socket.io/node_modules/redis/index.js:123:28)
    at Socket.emit (events.js:64:17)
    at Array.<anonymous> (net.js:830:27)
    at EventEmitter._tickCallback (node.js:126:26)

Clearly, the workers are failing to connect to Redis.

A bit of hacking around go me to this line:

io.set('store', new RedisStore);

My understanding is that the master is creating a Redis store and imposing Socket.io (and workers) to use it internally. Am I getting this right?

Am I supposed to somehow start Redis? Why is it failing to connect? Let me know.

Thanks!

[3rd-Eden]

@DavidChouinard yes it requires Redis to be installed and running.

[DavidChouinard]

@3rd-Eden Got it, thanks.

[rcombs]

I've seen people go back and forward on this; can Socket.io work with multiple processes (including Node native socket on 0.8.0) if RedisStore is used?