mod_jk is a conduit between a web server and Tomcat, it supports a variety of web servers including IIS. Using mod_jk to put Apache in front of Tomcat lets you use all the power of Apache (caching, gzip, mod_rewrite, etc) whilst at the same time serving content from Tomcat, also with Ubuntu it’s really easy to set up!
First of all install the software, you will need to enable the backports repository on Dapper for this.
apt-get install sun-java6-bin sun-java6-jdk tomcat5.5 libapache2-mod-jk
The Tomcat 5.5 that comes with Ubuntu already has an AJP connector configured on port 8009 so there is no additional configuration to do to it’s server.xml file.
We then need to configure a worker.properties file for Apache2 which tells it about the Tomcat instance, I make mine in /etc/apache2/worker.properties
worker.list=idimmu
worker.idimmu.type=ajp13
worker.idimmu.host=localhost
worker.idimmu.port=8009
Make sure mod_jk is then enabled with a2enmod jk (it probably already is).
And finally we tell Apache2 about the worker instance in /etc/apache2/apache2.conf
JkWorkersFile /etc/apache2/workers.properties
JkLogFile /var/log/apache2/mod_jk.log
JkLogLevel info
JkMount /* idimmu
This will direct any requests to the Apache2 server to the Tomcat server