Netty websocket server high availability

Question

I have looked at a similar question : Netty High Availability Cluster. The scenario I have is : There is a netty websocket server to which various native javascript web socket clients connect to. I am looking at basic high availability of the websocket server and want that it should fail over to a backup server if required.

The question in the above given link talks of netty clients but since I dont have the clients written in netty , I was thinking my scenario would be different from that question. Am I right?

Can someone suggest some way to do this since I guess this would be a fairly important requirement sometimes??

Answer 1

Because web sockets is connection oriented, if your server goes does, so does your web socket connection.

So, for high availability, I think you will need to adjust your javascript code to catch connection errors and reconnect/login.

In this way, you can put several netty servers behind a load balancer.

Hope this helps.

Answer 2

Assuming that you don't have control of your clients how about having a number of netty servers behind a traditional load balancer and storing session state in a hazelcast or infinispan cluster? Both platforms allow you to either embed them directly in your server, or have a remote cache.

Answer 3

Xitrum is very suitable for your need. It uses Hazelcast to scale out to multiple servers.

You can try the WebSocket demo.

To enable cluster mode, just set "multicast" and/or "tcp-ip" in config/hazelcast_cluster_member_or_super_client.xml to "true" and start multiple servers.