Client can not interact together when using nginx with socket.io

I have a chat application using socket.io. I put code on 2 server (ip1, ip2) and using nginx to make load balancing.

this is nginx config

upstream socket_nodes {
   ip_hash;
   server ip1:1654;
   server ip2:1653;
}
server {
 listen 1653;
 server_name livechatsoftware.com.vn;    
  location / {
  proxy_set_header X-Real-IP $remote_addr;
  proxy_set_header Upgrade $http_upgrade;
  proxy_set_header Connection "upgrade";
  proxy_set_header X-NginX-Proxy true;
  proxy_http_version 1.1;
  proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
  proxy_set_header Host $host;
  proxy_pass http://socket_nodes;
  proxy_redirect off;
 }
}

Everything is working well if clients connect to same server. but if client 1 connect to server ip1, client 2 connect to server ip2. client 1 and client 2 can not interact (eg cannot emit, send message,....)

Thanks for advance

I am using nginx to load balance my node processes (express.js + mongodb + socket.io + passport.js) . Although they are all in the same server, still socket.io events don't get shared between them. That means I've also faced the exact same issue. So I've used mong.socket.io (https://github.com/tmfkmoney/mong.socket.io) to store socket.io events in the mongo store. In that way each socket.io process reads the events from a centralized store.

You also need a central store which socket.io events can be accessed from any of the servers. I've never used that kind of setup but check out the below package;

https://www.npmjs.com/package/socket.io-redis

I'd install redis to one of my servers and point my socket.io processes to that server like below;

io.adapter(redis({ host: 'localhost', port: 6379 })); // you should use ip address and the port for the remote server

You can also use other adapter options as mentioned in the past link I've shared.