Ubuntu Hardy - Installing Apache Tomcat

Apache Tomcat is a free and open source implementation for JavaServlets. It provides support for Java Server Pages (JSP), which power many popular web-based applications.

You can run Tomcat with either Sun's Java implementation or OpenJDK, and this document provides instructions for both options.

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Choose a Java Implementation

Before we begin, you must choose an implementation of the Java language. Note there are some variances between them, and you should install a version that is compatible with the application you're planning to run or write.

OpenJDK

The "main" repository for Ubuntu comes with the "openjdk" implementation, which you would install with the following command:

sudo apt-get install openjdk-6-jdk

If you do choose OpenJDK, then you can skip the remainder of this section.

Sun Java

Sun's licensing terms are considered non-free under the guidelines that govern inclusion in Ubuntu's "main" software repositories. So If you wish to install Sun Microsystems' implementation of Java, you must first edit your slice's 'sources.list' file.

On your slice, use nano or your preferred text editor to append the following two lines to '/etc/apt/sources.list':

deb http://us.archive.ubuntu.com/ubuntu/ hardy multiverse
deb-src http://us.archive.ubuntu.com/ubuntu/ hardy multiverse

Update apt to get the necessary package lists:

sudo apt-get update

Now you're ready to install Sun Java with the following command (acknowledging the license terms):

sudo apt-get install sun-java6-jdk

With java in place on the slice, it's time to install Apache Tomcat.

Open Firewall for Port 8080

If you followed our initial setup guides for Ubuntu LTS, you'll probably need to open port 8080 in your slice's firewall. Otherwise, Tomcat will be inaccessible on your slice's public IP.

Go ahead and run through the iptables section of Ubuntu LTS Setup Guide. Then add the following line to your iptables rules:

-A INPUT -p tcp --dport 8080 -j ACCEPT

Installing Apache Tomcat

Download the latest version of Tomcat with the following command:

wget http://apache.mirrors.timporter.net/tomcat/tomcat-6/v6.0.20/bin/apache-tomcat-6.0.20.tar.gz

If you don't have wget installed, issue the command "sudo apt-get install wget" then try the download command again.

Extract the tomcat binary from the tarball with the 'tar' command:

tar -xzvf apache-tomcat-6.0.20.tar.gz

Then move the resulting Tomcat directory to a permanent location:

sudo mv apache-tomcat-6.0.20 /usr/local/tomcat

The scripts for controlling and interacting with Tomcat are located in the '/usr/local/tomcat/bin' directory.

Enable Tomcat to Start Automatically

Next create a tomcat "init" file:

sudo nano /etc/init.d/tomcat

Fill it with the following:

# Tomcat auto-start
#
# description: Auto-starts tomcat
# processname: tomcat
# pidfile: /var/run/tomcat.pid

export JAVA_HOME=/usr/lib/jvm/java-6-sun

case $1 in
start)
        sh /usr/local/tomcat/bin/startup.sh
        ;;
stop)
        sh /usr/local/tomcat/bin/shutdown.sh
        ;;
restart)
        sh /usr/local/tomcat/bin/shutdown.sh
        sh /usr/local/tomcat/bin/startup.sh
        ;;
esac
exit 0

If you installed OpenJDK instead of Sun Microsystem's Java, the export JAVA_HOME line should read:

export JAVA_HOME=/usr/lib/jvm/java-6-openjdk

Now make the script executable:

sudo chmod +x /etc/init.d/tomcat

Finally, create symbolic links in the startup folders:

sudo ln -s /etc/init.d/tomcat /etc/rc1.d/K99tomcat
sudo ln -s /etc/init.d/tomcat /etc/rc2.d/S99tomcat

Tomcat should now be totally functional and should start automatically when the slice reboots.

In the future, if you need to start, stop, or restart, you can use the following commands:

sudo /etc/init.d/tomcat start
sudo /etc/init.d/tomcat stop
sudo /etc/init.d/tomcat restart

Test and use Tomcat

Start Tomcat on your slice, and then test it by pointing a web browser to your slice's IP address. You should be greeted with Tomcat's standard "Congratulations!" page:


Note that by default, Tomcat servers content stored in '/usr/local/tomcat/webapps/ROOT/' .

Summary

Installing Tomcat is straightforward, whether you prefer OpenJDK or Sun's Java.

Your slice is now equipped with a free and powerful means to host JavaServlets!

—

Greg