Could not configure private pub on server connection being refused

Question

I am trying to configure private pub on my server on an ip, same configuration was working earlier on different server , but not working on current.

config/private_pub.yml

development:
  server: "http://52.76.xx.xx:9292/faye"
  #server: "http://faye.myserver.com/faye"
  secret_token: "secret"
test:
  server: "http://localhost:9292/faye"
  secret_token: "secret"
production:
  server: "http://example.com/faye"

private_pub.ru

# Run with: rackup private_pub.ru -s thin -E production
require "bundler/setup"
require "yaml"
require "faye"
require "private_pub"

Faye::WebSocket.load_adapter('thin')

PrivatePub.load_config(File.expand_path("../config/private_pub.yml", __FILE__), ENV["RAILS_ENV"] || "development")
run PrivatePub.faye_app

When I run rackup private_pub.ru -s thin -E production I get below

Thin web server (v1.6.4 codename Gob Bluth)
Maximum connections set to 1024
Listening on localhost:9292, CTRL+C to stop

But when I try to curl or call in browser, I get

Connection refused - connect(2) for "52.76.xx.xx" port 9292

I also tried with separate domain pointing to same IP for faye server and proxy it to localhost:9292 as below

server {
        listen       80;
        server_name  faye.myserver.com www.faye.myserver.com;
       # passenger_enabled on;

        location / {
            proxy_pass http://localhost:9292;
        }    
#       passenger_app_env production;
    }

But that also didn't work. Can you please tell me how to resolve the issue?