Is it safe to run multiple isolated instances of NodeBB and use LB to distribute load?

stevefan1999-personal

I use a k8s deployment and scale it up according to my need to run the cluster instead of using the official guide of using built-in worker cluster forking mode, so I think that maybe there will be some problem if I run that with k8s, and I think the most notable potential problem would be the websocket requirement? Because it is a stateful protocol, there can be some disassociation problem of message ordering/context difference.

I also see that I can add a Redis pubsub, and would that help solving this problem?

julian

@stevefan1999-personal Considerations when scaling NodeBB are detailed here: https://docs.nodebb.org/configuring/scaling/

... but possibly not in the most digestable way. In summary, here's what you need:

Redis configured in config.json so it will be used as pubsub and for storing user sessions (volatile data)
One of the workers needs isPrimary set to true in config.json, conversely, the other instances need jobsDisabled set to false
For socket.io, you will need to make sure to use a ip hashing strategy when routing requests from the load balancer. A typical round-robin style means the socket.io handshake will fail since it ends up hitting different servers.