JCR index configuration. You can find this file here: .../portal/WEB-INF/conf/jcr/repository-configuration.xml

<repository-service default-repository="db1">

  <repositories>

    <repository name="db1" system-workspace="ws" default-workspace="ws">

       ....

      <workspaces>

        <workspace name="ws">

       ....

          <query-handler class="org.exoplatform.services.jcr.impl.core.query.lucene.SearchIndex">

            <properties>

              <property name="index-dir" value="${java.io.tmpdir}/temp/index/db1/ws" />

              <property name="synonymprovider-class" value="org.exoplatform.services.jcr.impl.core.query.lucene.PropertiesSynonymProvider" />

              <property name="synonymprovider-config-path" value="/synonyms.properties" />

              <property name="indexing-config-path" value="/indexing-configuration.xml" />

              <property name="query-class" value="org.exoplatform.services.jcr.impl.core.query.QueryImpl" />

            </properties>

          </query-handler>

        ... 

        </workspace>

     </workspaces>

    </repository>        

  </repositories>

</repository-service>