title: Splitting MongoDB collections in multiple servers via mongos Router
body: <p>Having a MongoDB database named <code>maindatabase</code> which has 3 document collections named users, tags and categories, I would like to know if it is possible having them splitted on three different servers separately (on different cloud service providers). </p>
  
  <p>I mean not as a replica, but just one collection for server (one db with just categories collection on a server, one with users on another server and one for tags on the third server) may be routed by a mongos Router selectively.</p>
  
  <p>Anyone know if it is possible? </p>