title: Broadcast using Pub-Sub in multiple node instances
body: <p>I want to have 2 instances of the node server 'A' and 'B'.</p>
  
  <p>'A' will push connected clients [socket.io is used] in a room.</p>
  
  <p>'A' will publish an event to which 'B' is already subscribed.</p>
  
  <p>On receiving that particular event from 'A', instance 'B' will broadcast a message in the given room. Want to use the Room feature of socket.io</p>
  
  <p>Want to ask that, is it possible ? 
  I am trying redis store, but not getting how to publish an event so that server 'B' will receive it.</p>