title: Kafka on Multiple Servers
body: <p>I followed this <a href="https://www.digitalocean.com/community/tutorials/how-to-install-apache-kafka-on-ubuntu-14-04" rel="nofollow noreferrer">link</a> to install Kafka + Zookeeper. It all works well, yet I am setting up Kafka + Zookeeper on 2 servers. </p>
  
  <p>I have setup the <code>kafka/config/server.properties</code> to have:</p>
  
  <ul>
  <li>Server 1: <code>broker.id = 0</code></li>
  <li>Server 1: <code>zookeeper.connect = localhost:2181,99.99.99.91:2181</code></li>
  <li>Server 2: <code>broker.id = 1</code></li>
  <li>Server 2: <code>zookeeper.connect = localhost:2181,99.99.99.92:2181</code></li>
  </ul>
  
  <p><strong>I am wondering the follwing:</strong></p>
  
  <ul>
  <li>When I publish a topic, does it go to both Instances, or just the server it's loaded on?</li>
  <li>In order to use multiple servers like this, would I be required to use something like HAProxy with say 3 servers? </li>
  <li>Is there anything important I am missing with using 3 servers?</li>
  </ul>
  
  <p>Thanks for any answers.</p>