<div class="wiki-content maincontent"><h2 id="MasterSlave-IntroductiontoMaster/Slave">Introduction to Master / Slave</h2>

<p>The following are the different kinds of Master/Slave configurations available:</p>

<div class="table-wrap"><table class="confluenceTable"><tbody><tr><th colspan="1" rowspan="1" class="confluenceTh"><p>Master Slave Type </p></th><th colspan="1" rowspan="1" class="confluenceTh"><p> Requirements </p></th><th colspan="1" rowspan="1" class="confluenceTh"><p> Pros </p></th><th colspan="1" rowspan="1" class="confluenceTh"><p> Cons </p></th></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p> <a shape="rect" href="shared-file-system-master-slave.xml">Shared File System Master Slave</a> </p></td><td colspan="1" rowspan="1" class="confluenceTd"><p> A shared file system such as a SAN </p></td><td colspan="1" rowspan="1" class="confluenceTd"><p> Run as many slaves as required. Automatic recovery of old masters </p></td><td colspan="1" rowspan="1" class="confluenceTd"><p> Requires shared file system </p></td></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p> <a shape="rect" href="jdbc-master-slave.xml">JDBC Master Slave</a> </p></td><td colspan="1" rowspan="1" class="confluenceTd"><p> A Shared database </p></td><td colspan="1" rowspan="1" class="confluenceTd"><p> Run as many slaves as required. Automatic recovery of old masters </p></td><td colspan="1" rowspan="1" class="confluenceTd"><p> Requires a shared database. Also relatively slow as it cannot use the high performance journal </p></td></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p> <a shape="rect" href="replicated-leveldb-store.xml">Replicated LevelDB Store</a> </p></td><td colspan="1" rowspan="1" class="confluenceTd"><p> ZooKeeper Server </p></td><td colspan="1" rowspan="1" class="confluenceTd"><p> Run as many slaves as required. Automatic recovery of old masters.  Very fast. </p></td><td colspan="1" rowspan="1" class="confluenceTd"><p> Requires a ZooKeeper server. </p></td></tr></tbody></table></div>


<p>If you are using a shared network file system such as a SAN we recommend a <a shape="rect" href="shared-file-system-master-slave.xml">Shared File System Master Slave</a>. If you are happy to dispense with the high performance journal and are using pure JDBC as your persistence engine then you should use <a shape="rect" href="jdbc-master-slave.xml">JDBC Master Slave</a> instead.  For those willing to try out new tech, the <a shape="rect" href="replicated-leveldb-store.xml">Replicated LevelDB Store</a> gives speeds similar to a SAN solution without the hassle of having to setup a highly available shared file system.</p></div>