Omar Abdel-Wahab

Lucene is a very nice, robust and flexible search engine. The ways you can benefit from Lucene varies from small library system to a large e-commerce portal.
To unleash Lucene, you either have to use Lucene ported to your favorite language or install Solr and let Solr handle communication with Lucene.
Here we are going to install Solr on a Gentoo Linux box with Tomcat as the servlet container.
To get started, install Tomcat using:

# emerge tomcat

Default Tomcat configuration reserves the port 8080 for Tomcat which is fine unless you have another service running on that port.
Now let's download Solr:

~ $ mkdir solr
~ $ cd solr
~/solr $ wget http://www.poolsaboveground.com/apache/lucene/solr/1.2/apache-solr-1.2.0...
~/solr $ tar zxf apache-solr-1.2.0.tgz

Done with download and unpacking, installing Solr by copying its war file to Tomcat's webapps folder and copy the vanilla solr to solr-home:

~/solr $ cp apache-solr-1.2.0/dist/apache-solr-1.2.0.war /var/lib/tomcat/webapps/solr.war
~/solr $ cp apache-solr-1.2.0/example/solr solr-home

Now we need to specify where is our solr installation:

# echo 'export JAVA_OPTS="$JAVA_OPTS -Dsolr.solr.home=/home/USERNAME/solr/solr-home/"' >> /etc/bash/bashrc
# source /etc/bash/bashrc

Finally start Tomcat:

# /etc/init.s/tomcat-6 start

Browse to http://localhost:8080/solr/admin to make sure everything went fine.