I tried looking for documentation but it is quite sparse. I wrote the following guide hoping that it might save someone 2-3 hours dealing with installations, setup and configura
Install & Configure Tomcat:
Add the following roles and user to the configuration.
<role rolename="admin"/>
<role rolename="manager"/>
<user username="tomcat" password="password" roles="admin,manager"/>
Restart the server: /etc/init.d/tomcat6 restart
If all goes well, goto http://hostname:8080
Install Solr:
Install & Configure
vi /etc/tomcat6/Catalina/localhost/solr.xml
<Context docBase="/usr/share/tomcat6/webapps/solr.war" debug="0" privileged="true" allowLinking="true" crossContext="true"> <Environment name="solr/home" type="java.lang.String" value="/usr/share/tomcat6/solr" override="true" /> </Context>
You should see Solr access on your Tomcat admin/manager page (http://hostname:8080/manager/html)
Configure Magento to use Solr:
Replace the original Solr conf directory with the Magento conf files. The trick is just to copy the directory from Magento, and replace the one in Solr. That's it!
Troubleshooting:
Make sure all configuration files belong to tomcat6:tomcat6
chown -r tomcat6.tomcat6 ...