title: MySQL replication be bi-directional
body: <p>We have successfully set up a Master-Slave replication as described in MySQL literature. </p>
  
  <p>However, I'm curious if anyone has set up a bidirectional replication. For example, if one has a Drupal or Wordpress installation. The first ('master') database server goes down, and the secondary ('slave') picks up. All the while, users continue to make edits, writing new data. When the First database server is restarted, can changes written to the Second be replicated upward to the First?</p>
  
  <p>That is: are there other replication strategies than only the Master-Slave?</p>