Move the solrHome directory from the Search WAR to an external location. We recommend doing this by including the solrHome in the deployment package as a separate artifact and then deploying the artifact to the desired location on the server. This has two benefits:

• Replication configuration can be added without invading the WAR
• Search indexes are not deleted when a new WAR is deployed

Once solrHome is deployed to the desired location, add the JVM parameter -Dsolr.solr.home=<solrHomePath> to the appserver startup script.

Each config file in solrHome/conf has an <xi:include> tag that points to a corresponding replication configuration file.

<!-- include master/slave replication settings -->
<xi:include href="file:/etc/ep/product.solr.replication.config.xml" xmlns:xi="http://www.w3.org/2001/XInclude">
  <xi:fallback>
    <!-- Currently this reference is relative to the CWD. As of SOLR 3.1 it will be relative to the current XML file's directory -->
    <xi:include href="../replication/product.solr.replication.config.xml" xmlns:xi="http://www.w3.org/2001/XInclude">
      <!-- Silent fallback if no external configuration found -->
      <xi:fallback />
    </xi:include>
  </xi:fallback>
</xi:include>

In this case, Solr first looks for product.solr.replication.config.xml in /etc/ep and then in the ../replication relative path.The relative path is relative to where the Search server shell script is run.

If necessary, you can change the <xi:include> block in the Solr config files if /etc/ep is not an acceptable location.

Here is an example of the product.solr.replication.config.xml file.

<requestHandler name="/commerce-legacy/replication" class="solr.ReplicationHandler">
	<lst name="master">

		<!--Replicate on 'startup' and 'commit'. 'optimize' is also a valid value for replicateAfter. -->
		<str name="replicateAfter">startup</str>
		<str name="replicateAfter">commit</str>
		<!-- <str name="replicateAfter">optimize</str> -->

		<!--Create a backup after 'optimize'. Other values can be 'commit', 'startup'. It is
		possible to have multiple entries of this config string. Note that this is just for backup,
		replication does not require this. -->
		<!-- <str name="backupAfter">optimize</str> -->

		<!--If configuration files need to be replicated give the names here, separated by comma -->
		<str name="confFiles">schema.xml,stopwords.txt,elevate.xml</str>

		<!--The default value of reservation is 10 secs.See the documentation below . Normally , you
		should not need to specify this -->
		<str name="commitReserveDuration">00:00:10</str>
	</lst>
</requestHandler>

Create separate config files for each index you want replicated. You don't have to replicate all indexes--just the ones that are actually needed. Here is the full list of config files:

For each replication configuration file on the master, create a corresponding configuration file on the slave. Here is an example of the product.solr.replication.config.xml file:

<requestHandler name="/commerce-legacy/replication" >
	<lst name="slave">
		<str name="enable">true</str>
		
		<!--fully qualified url for the replication handler of master . It is possible to pass on this
		as a request param for the fetchindex command-->
		<str name="masterUrl">http://venus.elasticpath.net:8080/searchserver/product/replication</str>

		<!--Interval in which the slave should poll master .Format is HH:mm:ss . If this is absent slave does
		not poll automatically.
		But a fetchindex can be triggered from the admin or the http API -->
		<str name="pollInterval">00:00:20</str>

		<!-- THE FOLLOWING PARAMETERS ARE USUALLY NOT REQUIRED-->
		<!--to use compression while transferring the index files. The possible values are internal|external
		if the value is 'external' make sure that your master Solr has the settings to honour the
		accept-encoding header.
		see here for details http://wiki.apache.org/solr/SolrHttpCompression
		If it is 'internal' everything will be taken care of automatically.
		USE THIS ONLY IF YOUR BANDWIDTH IS LOW . THIS CAN ACTUALLY SLOWDOWN REPLICATION IN A LAN-->
		<str name="compression">internal</str>

		<!--The following values are used when the slave connects to the master to download the index files.
		Default values implicitly set as 5000ms and 10000ms respectively. The user DOES NOT need to specify
		these unless the bandwidth is extremely low or if there is an extremely high latency-->
		<str name="httpConnTimeout">5000</str>
		<str name="httpReadTimeout">10000</str>

		<!-- If HTTP Basic authentication is enabled on the master, then the slave can be configured
		with the following
		<str name="httpBasicAuthUser">username</str>
		<str name="httpBasicAuthPassword">password</str>
		-->

	</lst>
</requestHandler>

Add the following line to the ep.properties file on each slave server to stop the slaves from indexing themselves.

ep.search.triggers=disabled

Add the following line to ep.properties on the server containing the search master to identify which server contains the Search master.

ep.search.requires.master=true

Configure the searchHost server's URL through the system configuration setting: COMMERCE/SYSTEM/SEARCH/searchHost What URL you set depends on your deployment topology.